摘要:

COMPANY NEWS Monsanto/Pharmacia merger On 19 December 1999 Monsanto Company and Pharmacia & Upjohn announced that they had entered into a definitive agreement to create a dynamic and powerful new competitor in the global pharmaceutical industry. The new company will have one of the strongest sales forces in the pharmaceutical industry an expansive product portfolio a robust pipeline of new drugs including a number with blockbuster potential and an annual pharmaceutical R&D budget of more than $2 billion. The new company also will have one of the world’s leading fully integrated agricultural businesses. The combined company will have estimated 1999 sales of $17 billion with a market capitalization of more than $50 billion. The combined company to be named Pharmacia Corporation will have a significantly strengthened position in the critical U.S.pharmaceutical market and complementary current and near-term products in key therapeutic areas. Sales in the USA will account for more than 50% of the company’s global pharmaceutical sales. The agricultural business has a leading global position in seeds herbicides and biotechnology. In conjunction with the creation of the new company it is expected that up to 19.9 percent of the agricultural business will be offered in an Initial Public Offering (IPO). The agricultural business will become a separate legal entity with a stand-alone board of directors and its own publicly-traded stock upon completion of the intended IPO.The new company’s corporate headquarters will be located in Peapack N.J. along with the pharmaceutical business. The new company’s agriculture business will be headquartered in St. Louis. Under the terms of the merger-of-equals transaction which has been unanimously approved by both boards of directors Pharmacia & Upjohn shareowners will receive 1.19 shares of the combined enterprise for each share of Pharmacia & Upjohn they now hold. Each Monsanto share outstanding prior to the combination will represent one share in the combined company. The transaction will be tax-free to the shareowners of both companies and is expected to be accounted for as a pooling of interests. Monsanto shareowners will own approximately 51 percent of the combined company’s shares.Please send any contributions to the NEWS sections in Pesticide Outlook to Hamish Kidd The Royal Society of Chemistry Thomas Graham House Science Park Cambridge CB4 0WF. FAX +44 (0)1223 420247; email KIDDH@RSC.ORG. Rohm and Haas …modernises its biocides site at Jarrow UK In the UK the $14 M modernisation of Rohm and Haas’s biocides site at Jarrow has been completed by the UK engineering company Eutech. New equipment has been provided to reduce emissions into air and water and the site has quality certificate ISO 14001. The quality of the isothiazolones-based biocides produced on this site will now be equivalent to that of those made on the group’s 1996-built site at Bayport Texas USA which was extended by 40% in 1998.The UK site now has maximum safety and flexibility. Rohm and Haas has $130 M/y worldwide turnover in biocides and is the leading producer of isothiazolones. There are 4 different active ingredients in Rohm and Haas’s range of isothiazolones which are for use in the water treatment wood treatment cosmetics paints and plastics industries. The anti-fouling products Sirena ASR 2 Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 Sumitomo Chemicals …acquires Abbott Laboratories’ agrochemicals business Japanese group Sumitomo Chemical has announced its acquisition of U.S. group Abbott Laboratories’ agrochemicals business. This consists mainly of biological products for plant protection and growth regulators.Based in Lake County Illinois it employs 164 people and in 1998 made a $103 M turnover (1% of Abbott’s sales). The US group retains production rights to its active ingredients. The acquisition will increase Sumitomo’s range of products for organic farming and consolidate its position in North America Europe and Oceania. …acquires production facility in India Sumitomo plans to acquire a 90% stake in New Chemi Industries’ (NCI) (India) agrochemicals division. The deal is expected to close early in 2000. Sumitomo will upgrade NCI’s existing site in Mumbai India. Production of a mosquito repellent will begin mid-2000. Sumitomo already supplies the Indian market from Japan. Dow AgroSciences …to cut 700 jobs Dow AgroSciences is cutting 700 jobs worldwide.It will close its Mycogen Seeds facility in Minnesota. Dow’s agribusiness is the latest casualty in a series of cutbacks by agri-product suppliers hit by the depressed US farm economy. It will consolidate the Minneapolis facility’s activity in Indianapolis where Dow AgroSciences is based. Dow says the cuts are an effort to combat challenging business conditions. The company believes that the growth of generic products and the emergence of biotechnology have slowed anticipated growth in its conventional agrochemicals business. …research agreement with Biotica Technology Ltd. Dow AgroSciences LLC and Biotica Technology Ltd (Biotica) announced a twoyear research agreement that may lead to additional uses of spinosad an insect control product.Spinosad is derived through the fermentation of a naturally occurring organism. It controls a variety of insect pests including caterpillars thrips flies drywood termites and some beetles. Under the terms of the agreement Biotica will determine the potential for obtaining additional variants of spinosad by targeted changes of the biosynthetic pathway that creates this product. Monsanto and Novartis settle patent disputes A settlement has been reached between Monsanto and Novartis concerning pending lawsuits over Monsanto’s DeKalb seed unit. The lawsuits relate to royalties and licences for genetically modified Bt corn seeds Novartis NK Novartis NK YieldGard corn and Novartis Knockout corn.Lawsuits had been filed by both companies relating to contractual and intellectual property rights concerning Bt corn. All pending lawsuits are settled by the agreement including the patent infringement lawsuit of Monsanto against Novartis in several U.S. states and the mutual breach of contract lawsuits in Minnesota and Missouri. Under the terms of the agreement Novartis has agreed to pay Monsanto licensing fees and future royalties and fees for genetically modified organisms. In return Novartis will receive improved and simplified licence terms for the corn and royalty bearing licences for glyphosate resistance in corn. based on Sea-Nine 211 a biocide supplied by Rohm and Haas are being tested by Colorificio Baseggio in Venice are tested as anti-fouling paints without tin for use on fishing and passenger boats.…new fungicide plant in China A dithane production unit is being constructed by Rohm and Haas Nantong Chemical in Jiangsu China. The plant due for a late 2000 start-up will serve the company’s domestic market. Akzo Nobel finalizes acquisition of Hoechst’s animal health business Akzo Nobel has successfully completed negotiations for the acquisition of Hoechst’s animal health business. The deal worth EUR 655 M will make Akzo Nobel the 4th largest group in the sector. At the end of November 1999 the European Commission approved the deal on condition that the groups withdraw from certain sectors where they would have too dominant a position.The acquisition (which includes all production units and research and development installations and will affect 2400 employees) will double the size of Intervet (Akzo’s veterinary products business). Its turnover will increase to EUR 800 M. Mitsui increases European presence in biopesticides A 60% stake in Biological Crop Protection UK has been acquired by Mitsui and Co. The deal – the first involvement of Mitsui in the predator insects sector – enhances the Japanese company’s position in the Integrated Crop Management Meeting In today’s world the majority of the general public is taking a greater interest in the quality of its food than ever before. Recent crises in Europe have taken the public’s mind off pesticide residues in food but the US Food Quality Protection Act (FQPA) is raising these issues in the minds of US citizens and it will not be long before they are back with the Europeans.Nevertheless we are told that organic food consumption is increasing at a rate of 25% or more each year as customers are persuaded that such food although more costly is better for them and their families. So where does Integrated Crop Management (ICM) fit in? ICM involves the application of compounds as and when needed with the preferred treatments being none at all. As and when necessary natural crop protection systems are employed with chemical methods used only when the alternative is complete crop loss.It is an integration of all the methods available to us but only when they are needed. It is a method demanded by supermarkets for the production of their fresh fruit and vegetables. It is being encouraged in developing countries as an answer to pest problems in subsistence farming. And it works. The Volcani Centre Israel and the Fresh Produce Consortium UK have joined with the Crop Protection Group of SCI to organise a meeting ‘The Economic European market for biological pesticides. Sales of BCP amount to £2 M/year and it is the world’s third largest producer of predator insects. Within five years the company aims to increase sales to £6.25 M/year including its operations in Japan and North America. Sales in Europe are expected to be assisted by a trend away from the use of chemical insecticides.Agent Orange 2000 South Korean veterans of the Vietnam War have filed a lawsuit in Korea seeking $321 M in damages from US producers of Agent Orange. A ruling in Seoul is expected shortly. Companies cited in the lawsuit are Monsanto Co and Dow Chemical Co. Veterans want to receive compensation before 2004 at the latest. Both companies have business operations in South Korea. Early in 1999 the veterans won an injunction that froze the sale or transfer of hundreds of the companies’ patent rights in South Korea pending a ruling. Legal authorities say that if the veterans win and the companies refuse to compensate them the patent rights can be disposed of.The suit is part of a broader legal battle being waged by 17,000 South Korean veterans of the Vietnam War who are seeking $4.3 bn in compensation from Dow and Monsanto. Hearings on that suit have yet to begin. Former soldiers are also seeking $1 bn in compensation from the US government. Early December 1999 both the US and South Korean governments acknowledged that Agent Orange had been used on the North Korea border in 1968/69. South Korean officials say that at South Korean veterans of Vietnam sue manufacturers of Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 COMPANY NEWS least 50,000 soldiers manually sprayed Agent Orange and two other defoliants along the demilitarised zone.The herbicide contained dioxins (as impurities) which are linked to certain types of cancer. Snippets …Zeneca Agrochemicals is to launch its new herbicide mesotrione [ 2-(4-mesyl-2- nitrobenzoyl)-3-hydroxycyclohex-2-enone] for use on maize from 2002. A new production plant will be built at Cold Creek Alabama in 2000. Mesotrione is currently being reviewed under the EPA’s fast track pesticide reviewing scheme. …Novartis’ animal health division is to acquire UK company Vericore which specializes in vaccines parasiticides and other products for cattle as well as drugs for pets and aquaculture. …United Phosphorus Ltd has filed a lawsuit in the US federal district court in Wilmington Delaware seeking at least $56 M from BASF Corp and its subsidiary Micro-Flo over their alleged importation of millions of pounds of unregistered pesticides for distribution sale and use in the US. …the surfactant hamposyl from Dow’s US subsidiary Hampshire Chemical Corp improves plant uptake of glyphosate without the operator and environmental risks presented by tallow amine alternatives. Hamposyl is based on a sarcosinate compound (similar to those used in toothpastes and shampoos) and is being offered to Monsanto and generic glyphosate producers. and Commercial Impact of Integrated Crop Management’ to be held at 14/15 Belgrave Square London SW1X 8PS from 3–4 April 2000. There are four sessions ICM Facts and Perceptions; ICM in Practice; ICM Case Studies; and ICM The Wider Picture and an international group of speakers has been invited to address these topics. Posters are invited for any aspect of ICM that falls into these categories. The full programme can be seen on the SCI web site (http://www.sci. mond.org). For further details on the conference or offers of posters contact Deborah Norcross at Belgrave Square (Tel +44 (0)207 598 1563; email:deborahn@chemind.demon. co.uk). 3

ISSN:0956-1250    

DOI:10.1039/b006288j

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

REGULATORY NEWS OP sheep dips The UK Government announced on 20 December 1999 that OP sheep dips will be withdrawn from the market until modified containers are available to minimise operator exposure to dip concentrate. This measure is stated to be part of an action plan which includes revoking marketing approvals for three OP compounds used in veterinary medicine other than sheep dips and for which full safety data have not been submitted. Other measures in the plan are - implementing a range of measures to promote good practice and conducting a targeted research programme to implement recommendations made by the Committee on Toxicity of Chemicals in Food and other advisory committees. The National Office of Animal Health (NOAH) the industry association which represents manufacturers of animal medicines has expressed astonishment that the Government has “felt the need to resort to precipitate action on OP dips by recalling all current packs within 20 working days” with sheep farmers having to return their stocks to distributors who then have to return them to manufacturers.All this had to be done by 31 January 2000. This was described by NOAH as a “seemingly impossible task”. Regulatory and advisory committees have noted that whilst possible ill-health effects from prolonged exposure to OPs remain unproven there remains a question of whether there may be a small group of individuals who are particularly susceptible to OPs. France to tax agrochemicals on ecological risk French farmers face taxes on their use of agricultural chemicals.Pesticides are being grouped into seven categories depending on their ecological risk and taxed up to FFR 11/kg active ingredient. For example the insecticide aldicarb (Temik) will be taxed at FFR 1.1/kg raising the price to FFR 11/ha. Revenue of some FFR 300 M is initially expected. Fertilizer is expected to be included in the scheme soon. The measure has been ratified by the Council of Ministers and government approval is expected in time for its introduction in January 2000. 4 California pesticide use increased in 1998 Preliminary figures released by the California Department of Pesticide Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 Regulation (DPR) indicate that overall pesticide usage in the state increased by 5% in 1998 to 215 M pounds.The use of reduced-risk pesticides increased by over 350% to 330,882 pounds. Cholinesteraseinhibiting pesticide usage fell nearly 20% from the 1997 usage of 16.2 M pounds. Sulfur usage rose by 13.7 M pounds. Diazinon use was down from 955,000 pounds to 874,662 pounds with chlorpyrifos usage down from 3.2 M pounds to 2.4 M pounds. Use of pesticides classed as reproductive toxins was about 29.5 M pounds (32.6 M pounds in 1997). Methyl bromide usage was down from 15.7 M pounds to about 13.9 M pounds. ‘The Future of Food’ Chamber of Commerce meeting The Chamber of Commerce USA held the first of three conferences in November 1999 which will examine ‘The future of food’.Speakers considered that industry has the main role in ensuring the safety of food. There will be a need for food regulation to change with new food additives pesticides and genetically modified foods. In particular more detailed risk analysis will be required for banning existing products such as pesticides as well as for approval of new products. Such an analysis has been carried out for organophosphates and carbamates. The health risks from these pesticides in food is small whereas several risks from banning the pesticides are listed including the return of pests that are responsible for other health problems. The US-EPA is now considering aggregate risks of each pesticide and its ingestion from food and water and by contact such as children rolling on a lawn.The introduction of zero tolerance is now considered to have been an overreaction. GM crops …GM labelling required only if content above 1% In the UK foods containing genetically modified (GM) ingredients will not have to declare that is the case on the label so long as the GM content of any particular ingredient does no exceed 1%. It is intended that the new threshold will overcome the difficulty of manufacturers who attempt to produce GM-free produce but find that there is a small amount of contamination because of imperfect separation procedures. The lobby group Greenpeace and some members of the European parliament felt that the 1% threshold was too high but they have welcomed the move in principle.However the US trade mission in Brussels said that 2% would have been more appropriate given that the majority of trade contracts have 2% admixture tolerances. Overall it is still opposed to the process of GM labeling because it claims it raises costs when there are no health risks involved. The EC expects to apply the rules to all GM organisms although at the moment they only apply to ready approved GM soybeans and maize. …UK ban on GM crops to be extended The UK government has announced a 3- year extension to the voluntary ban on commercial growing of genetically modified (GM) crops. The Environment minister has said that there will be no commercial plantings of GM crops until after the farm-scale evaluations were completed.In 1998 the farm-scale trials began and are scheduled to be completed in 2002. The results are intended to quantify the effect on biodiversity of growing GM crops. The government is sticking to its position that there are no legal scientific or safety reasons for any ban or moratorium. The Supply Chain Initiative on Modified Agricultural Crops says the trials would help to build up public confidence in GM crops by progressing on the basis of sound science. …Bt corn poses little risk to monarch butterflies The Agricultural Biotechnology Stewardship Working Group which includes five agricultural biotechnology companies commissioned research with $100,000 of industrial funds to study the effects of pollen travelling from Bt maize fields on monarch caterpillars feeding on nearby milkweed plants.Preliminary results suggest there are few risks but counter arguments are cited. The US-EPA may introduce changes for the 2000 growing season based on the results of research. FDA public meetings on regulation of GM foods Consumer groups in the USA have called for labelling of genetically engineered foods. The US-FDA only seeks such labelling if the nutritional value of the genetically modified food is substantially different from its conventional analogue or if a gene from a known allergen is added to a food. There are more than 40 genetically modified food products being sold mainly modified with Bacillus thuringiensis to kill insect pests or to resist a company’s herbicide.In 1999 about 33.3% of maize and 50% of soybeans grown in the USA were genetically modified. Other crops often so altered include cotton canola and potatoes. Spray drift On 14 December 1999 the US Environmental Protection Agency (EPA) issued a factsheet on their position on pesticide spray drift which can expose people wildlife and the environment to detrimental levels of pesticides. Sections in the factsheet include l What is pesticide Spray Drift? l How Does Spray Drift Occur? l What are the Impacts of Spray Drift? l How Does EPA View Off-Target Spray Drift? l How Does EPA Help Protect People and the Environment from Off-Target Spray Drift? l Other Activities that Promote Awareness and Education of Spray Drift Issues l Where to Direct Complaints About l Spray Drift l Further Information The fact sheet can be viewed on http://www.epa.gov/pesticides/citizens/spra ydrift.htm Legislation to seek notification before pesticide use in schools The US is considering legislation to ensure that parents are notified before pesticides are sprayed around schools.The legislation would require schools to notify parents 72 hours before pesticide use. Supporters of the legislation say it is needed because children are vulnerable to pesticides because their immune and nervous systems are still developing. Some states including Maryland and Connecticut have passed laws requiring parental notification.Endocrine disruption In December 1999 the UK Government signed an agreement with Japan to collaborate on research into endocrine hormone disruption in the aquatic environment. A workshop is to be held for UK and Japanese scientists to exchange information on existing research and identify possible areas for cooperation and Please send any contributions to the NEWS sections in Pesticide Outlook to Hamish Kidd The Royal Society of Chemistry Thomas Graham House Science Park Cambridge CB4 0WF. FAX +44 (0)1223 420247; email KIDDH@RSC.ORG. collaboration. The UK side will be coordinated by the Interdepartmental Group on Endocrine Disrupters led by the Department of the Environment Transport and the Regions (DETR).EPA proposes antimicrobial registration requirements A rule to regulate the registration requirements for antimicrobial pesticide products has been proposed in the US by the Environmental Protection Agency (EPA). Registration procedures would be created together with labeling standards for antimicrobial health products and a modification of the notification process for conformation to the statutorily prescribed process. The ruling would also require the implementation of certain efficacy performance standards and limit the duration of registrations bearing public health claims to five years. The proposed requirements will facilitate the promotion of international harmonization efforts.Pesticide residues in potatoes The independent Advisory Committee on Pesticides in the UK has considered results from a survey covering residues of the pesticide aldicarb in potatoes. The committee has concluded that even consumers of large quantities of potatoes with the highest residues detected would be unlikely to suffer any adverse health effects. This survey marks the end of a long-term programme which has confirmed that there can be considerable variation in residues between individual units of fruit and vegetables. UK labelling of organophosphates and carbamates The Pesticides Registration Section of the UK’s Health and Safety Executive (HSE) and the Pesticides Safety Directorate (PSD) are currently carrying out a review of all anticholinesterase (organophosphate and carbamate) compounds present in agricultural and non-agricultural pesticide formulations.Ministers initiated the review because of growing public concern over the use of these compounds. A re-labeling strategy has been agreed by the Advisory Committee on Pesticides to help inform and educate pesticide users. This will mean that all new and current pesticidal formulations containing organophosphate/ carbamate compounds will have an Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 REGULATORY NEWS additional warning incorporated into the product label phrases. On 10 January 2000 PSD issued an update of progress on its review of anticholinesterase compounds.As of 18 Septamber 1999 a total of 17 compounds had not been supported by approval holders. Dossiers had been received for 21 of the remaining substances; PSD is now working on Phase III of the review of these active substances and is conducting initial examinations to see if they are suitable to support continued approval of the products; the findings will be presented to the Advisory Committee on Pesticides. A further 2 active substances (fenpropimorph and butoxycarboxim) has now been added to the data call-in with a data submission deadline of September 2000. “No Pesticides Day” On December 3 1999 Pesticide Action Network (PAN) groups around the world observed “No Pesticides Day” with a host of activities to draw attention to the possible life-threatening impacts of chemical pesticides on people and the environment.This date was chosen to honor those who died as well as those still suffering as a result of the 1984 disaster in Bhopal India. Launch of PAN International Web site The PAN International Web site was launched on No Pesticides Day. The Web site was developed by PAN North America in collaboration with the other PAN Regional Centers. The site is a comprehensive entry point on the Web to the entire international PAN network. It offers information about PAN and its international work and links to each Regional Center’s Web site. The address is http://www.pan-international.org. “The current trends of globalization and the industrialization of agriculture are promoting intensive use of hazardous pesticides which has increased the suffering of millions of people in rural agriculture and the plantation sector the world over,” stated Sarojeni V. Rengam Executive Director of PAN Asia and the Pacific. “Each year approximately three million people are poisoned and 200,000 die from pesticide misuse. While many of the reported ill-effects are acute cases of pesticide poisoning chronic long-term effects such as cancer and reproductive problems are of increasing concern.” 5

ISSN:0956-1250    

DOI:10.1039/b006291j

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

R&D NEWS Flazasulfuron the new grapevine herbicide Flazasulfuron was discovered by ISK Biosciences and developed by Zeneca under the brandnames Mission and Katana. It is the first member of the sulfonylurea family of chemicals to have shown good selectiveness on vines. In France it is approved for use as a vine herbicide at doses of 50 g/hectare. It is absorbed through the leaves and roots of both monocotyledons and dicotyledons and need only be applied once. It is the first sulfonylurea capable of rapid detoxification in vines. Flazasulfuron like other sulfonylureas inhibits the synthesis of 3 essential amino acids in susceptible plants. Zeneca's herbicides Mission and Katana are sold in waterdispersible granular formulations and contain 25% flazasulfuron.Biofumigants Australian research at CSIRO Plant Industry Communication has revealed that glucosinolates from brassica crops such as rape and mustard reduce the growth of soil-borne pathogens such as those causing take-all disease in cereals. Glucosinolates in the roots breakdown in the soil to produce isothiocyanates potent fumigants. These natural pesticides have been termed biofumigants. The findings explain why brassica crops such as oilseed rape are good break crops. For further information email info@pi.csiro.au Research agreement between DLO and AgrEvo Stiching Dienst Landbouwkundig Onderzoek (DLO) and Hoechst Schering AgrEvo have signed a research agreement concerning the functional analysis of the genes of several major plant species.The agreement involves DLO's Centre for Plant Breeding and Reproductive Research in Wageningen in the Netherlands and AgrEvo's Plant Genetic Systems based in Gent Belgium. 6 Elf Atochem find Aminoguanidine bicarbonate (AGB) has been developed by Elf Atochem specifically as a synthesis intermediate. The company says AGB is designed for the agrochemical and pharmaceutical industries in specific applications such as the synthesis of fungicides in addition to various chemical synthesis operations to achieve purification stages in wide-ranging areas. Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 Biodegradable decoys AgrEvo wins pesticide packaging award with Echo System A packaging design award has been won by AgrEvo for the Echo System pesticide container.The returnable 25-litre polythene keg has a stainless steel valve that is compatible with transfer systems using the Micromatic type valve; spillage and waste on the farm are minimised. So far only two products are available in the containers Cheetah (fenoxaprop) and Arelon (IPU). …biological alternative The Institute of Arable Crop Research at Biodegradable apples that attract apple Rothamsted UK is coordinating research maggot flies (Rhagoletis pomonella) and on developing a sustainable alternative to other insect pests in orchards has been the use of methyl bromide in southern patented by USDA-ARS scientists from the Europe for fumigating soil and controlling National Center for Agricultural nematodes.The research using the fungus Utilization at Peoria Illinois along with Verticillium chlamydosporium is being colleagues at the University of carried out in Italy Spain Portugal and Massachusetts at Amherst Michigan State Greece and is financed by the EU. University at East Lansing and the Biotechnology Research and Development …dazomet Corporation at Peoria. The inside of the According to Hortichem the use of spherical decoys consist of sugar high- contractor-applied Basamid (dazomet) to fructose corn syrup water corn flour and fumigate arable soils is a realistic sorbic acid. The outside is a coating of alternative to threatened methyl bromide sugar latex enamel paint and an insecticide fumigation.Growers should use an (e.g. imidacloprid). Preliminary field approved contractor however. The tests in Massachusetts showed that the company has developed procedures which decoy fruit hung in trees at the edge of are to form the basis for best practice for its orchards may provide an alternative to approved contractors. repeated chemical insecticide sprays maintaining 70% of its insect-killing power after 3 weeks. In other tests a similar decoy protected apples as well as 3 spray applications of azinphos-methyl. Decoys The Plant Protection Research Institute in are also being designed and tested against South Africa has reported that the larger related insects such as blueberry maggot grain borer (Prostephanus truncatus) has fly the cherry fruit fly and the walnut husk fly.Couch and brome control for wheat Monsanto has developed a new sulfonylurea herbicide code named MON36500 (sulfosulfuron) for which the company claims couch and brome control in winter wheat plus useful broad-leaved weed action from spring spraying. The ingredient is already available in Ireland as Monitor and UK approval is planned for the spring 2000 growing season. It does not kill couch or brome but suppresses them keeping the weed below the crop canopy at critical growing times. Yield response is claimed to be up to 20% from brome control and 40% from couch control. Methyl bromide replacements …1,3-D Mixtures of 1,3-dichloropropene (1,3-D or Telone) and chloropicrin are promising methyl bromide replacements but regulatory controls for 1,3-D are causing concern.The US-EPA requires a 300 foot buffer zone which could be overcome with new methods of application. The worker handling problems may be reduced with drip irrigation systems or filtered and air conditioned cabs. Larger grain borer moving south in Africa been found in the Kruger National Park near the border with Mozambique. The South African authorities have drawn up contingency plans to control this pest of stored maize; increased monitoring through the use of pheromone traps; ensuring stocks of insecticide are available; and training extension staff and scientists in how to recognise and deal with the problem.If not controlled the pest could spread throughout South Africa wherever maize is grown causing widespread stored grain losses. Oilseed rape trial reveals growth regulation effects of fungicide Trials by the UK's National Institute of Agricultural Botany (NIAB) suggest that Folicur (tebuconazole) fungicide offers support for weak-stemmed oilseed rape varieties. The Apex variety surpasses everything else when it comes to a combination of stem stiffness and lodging resistance but some of the more recently introduced varieties are certainly not as stiff and this could be restricting their uptake. Trials indicate that applying Bayer's Folicur in the spring could offer many benefits. Spring application of Folicur was shown to increasing lodging resistance of all five varieties tested.Disease control was also improved. Further trials will be carried out but Bayer is confident that Folicur improves the standing ability of weak-stemmed varieties. Contribution of pesticides in control of New York virus outbreak Pesticides gained valuable publicity when New York was hit recently by an outbreak of West Nile virus the first time the deadly ailment has been seen in the Americas. The city mayor has been at the forefront in encouraging the spraying of insecticides against the mosquito vectors malathion was applied from the air in New York sumithrin from the air in Westchester County and resmethrin from truckmounted foggers in Connecticut. Pest control companies increased their business without marketing effort or the need to defend their products.It is feared that regions further south of the affected area may suffer the disease as birds carrying the mosquitoes migrate south for the winter and floods left by Hurricane Floyd provide harbourage for the insects. FOCUS ON BIOPESTICIDESPLUS Focus on BiopesticidesPLUS is an international newsletter that reports on uses of natural organisms their genes and their secondary metabolites in crop protection. It provides vital production market company and regulatory news. The newsletter is edited by Len Copping who is well-known for his work in this area with analysis and comment provided by him and other experts in the field. Information is drawn from technical and commercial sources including company literature press releases and market research reports in addition to journals.Focus on BiopesticidesPLUS is essential reading for all those working in this sector. For a FREE sample issue contact Sales and Customer Care Royal Society of Chemistry Thomas Graham House Science Park Milton Road Cambridge CB4 0WF UK. Tel +44 (0)1223 420066. Fax +44 (0)1223 423429. e-mail sales@rsc.org. Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 Blackgrass weed fight BASF's new herbicide tepraloxydim offers growers a new weapon in the fight against blackgrass and couch in broad-leaved crops. It might be especially useful for growers combating resistance since tepraloxydim is much more active than fops and other dims.Trials show 83% control on all populations of blackgrass. Approval for use on sugar beet beans peas and winter oilseed rape is expected for second quarter 2001. Neem pesticides …the Indian Institute of Chemical Technology (IICT) Hyderabad was issued US patent number 5856256 for a pesticidal dry powder formulation enriched in azadirachtin up to 88% and an emulsifiable concentrate up to 30% of azadirachtin from neem seed/kernel. The new pesticidal formulation will be used in pest control formulations developed for agriculture veterinary and public health applications. …a new bioinsecticide containing different concentrations of neem oil and neem seed extract has been developed to combat Latoia lepida a phytophagous pest commonly found in mango cassia and in some agricultural and horticultural crops.Laboratory experiments showed that larvae infestation could be controlled through the application of 0.25% neem oil or 0.5% concentration of neem seed kernel extract. The bioinsecticide is also economically viable and environmentally safe. R&D NEWS Bioinsecticide wards off grain pests Scientists at the Central Food Technological Research Institute (CFTRI) in Mysore have prepared a new ecofriendly bioinsecticide that is effective against stored food grain pests such as rice weevil grain borer and rust-red flour beetle. The bioinsecticide is a dried powder extract from the roots of Decalepsi hamiltoni (also called swallowroot). At 5% concentration the insecticide was 96% effective and 99.97% effective at 10% concentration. Imidazolinone-tolerant sugar beet A licensing agreement for the application of new technology to control weeds in sugar beet has been signed between Michigan State University and American Cyanamid. Without the use of genetic modification new varieties will be developed which will be tolerant to imidazolinone herbicides produced by American Cyanamid. These are broad-spectrum products which are environmentally compatible. An application for approval of the use of imidazolinone on sugar beets has been made by American Cyanamid. The development of the tolerant varieties will remove the need for a lengthy rotation period when growing sugar beet on land used for crops treated with imidazolinone herbicides. 7

ISSN:0956-1250    

DOI:10.1039/b006292h

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

MILLENNIUM ESSAY CROP PROTECTION INDUSTRY – RETOOLING FOR A NEW TOMORROW Elmo Beyer and Forrest Chumley of DuPont Agricultural Enterprise Wilmington Delaware in the USA look forward to the impact which new technologies will have on the crop protection business middle of the next century. With limited arable land major breakthroughs in technology will be essential to achieve such a daunting task. Introduction Catalyzed by strong competitive forces in crop protection chemicals and promising new business opportunities in biotechnology the agrochemical industry is currently undergoing a major restructuring and metamorphosis. This transformation is characterized by mergers acquisitions joint ventures and alliances. Although such changes have been underway for some time their intensity has dramatically increased in recent years.A key impetus for this rapid transformation is the highly competitive nature of the agrochemical market fuelled by slow market growth reduced rate of technological innovation and depressed farm prices. Many analysts believe these conditions are not likely to subside soon because they believe there are too many companies spending too much money pursuing too few opportunities. Broad-based and costly R&D programs are needed to achieve breakthroughs in pest control technology. Without such breakthroughs companies are finding it increasingly difficult to remain viable and grow especially in an industry where real growth has averaged only 1.2% per annum since 1990. As a result many well-known agrochemical company names have disappeared and are being replaced by fewer but larger entities such as Aventis Syngenta and Dow AgroSciences.A second major impetus for rapid change is biotechnology. Many of the dominant players are using biotechnology as a springboard to create new market opportunities beyond traditional crop protection chemicals. By acquiring or forming joint ventures with companies in the seed and downstream food and feed markets these players clearly intend to create global integrated agrobusiness enterprises. During the last two years alone Monsanto and DuPont have spent over 18 billion dollars pursuing this strategy. Retooling of research for more effective new product discoveries is also an integral part of the current restructuring.World-class competencies in chemistry and genetics are being linked synergistically through biotechnology to build robust flexible and responsive technology platforms to create new product offerings. Researchers are designing the next generation of crop protection chemicals as well as genetically engineering crops and biologicals for improved pest control yield and quality. These genetically enhanced products are targeted not only at farmers but also at livestock producers processors and other end-users of foods feeds and biomaterials. Over the next 30 to 40 years agricultural productivity must be increased by 3-fold to feed the burgeoning world population which is expected to reach 8.5 billion near the Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 Feeding the world’s population in the 21st century Currently world population is growing by about 80 million per year increasing the annual demand for grain by about 26 million tons.The increase in population growth is not expected to stabilize until around 2035 resulting in 2.5 billion more people to feed.1 This increase and the concomitant demand for grain especially corn wheat rice and soybeans will continue to place tremendous pressure on today’s global agricultural production systems. Moreover meeting the challenge of increased grain production cannot wait since in 1996–1998 world grain reserves stood at the lowest levels ever recorded only enough to meet global needs for less than 60 days.2 The demand for grain is increasing as the standard of living in developing countries improves because of the desire of many people to eat more meat and animal products.As more meat is consumed the requirement for feed grains dramatically increases since about 7 pounds of grain are required for each pound of beef produced. Thus as affluence increases in the developing nations a 40% increase in world population could translate into a need for a 200-300% increase in grain production. It is paramount that over the next decade agricultural production keeps pace with growing population because of the strong evidence that meeting or exceeding basic requirements for food is an essential first step in moderating population growth.Historically farmers have met the need for increased production by clearing and cultivating new land and by increasing the unit productivity of the land being farmed. In today’s world expanding the area under cultivation is no longer a viable option. Indeed in many areas around the world societies are struggling to prevent the loss of prime farmland. In India and China for example combined population growth of nearly 750 million by 2030 is expected to result in a demand for construction of nearly 100 million additional residential units. Moreover economists are projecting the simultaneous construction of 1.5–2 million new factories. Because of the proximity between prime agricultural land and the major centers of growth and development it is inevitable that much of the land for new construction will continue to come at the expense of farmland.In 1950 per capita grain area peaked at about 0.23 hectares per person; and by 2030 it will be 8 one-third this amount or 0.08 hectares per person.3 A global struggle is clearly underway to produce more food on a shrinking arable land base. Increasing the productivity of existing farmland offers the only realistic hope for meeting the food production challenges of the next century. The modern green revolution has resulted in the basic food sufficiency enjoyed today by most of the world’s population. Since 1950 global average grain yields per hectare have increased by a factor of nearly three.4 This increase has been achieved by development of new crop varieties that are highly responsive to a wide range of improved agronomic management practices for maximum yield.Some of these new varieties have shorter days to maturity permitting double or even triple cropping in the tropics. Modern crop protection methods along with the optimum use of other inputs have been essential for realizing the full potential of these new varieties. It is estimated that the dramatic increase in yields since the 1950s has spared the clearing of over 12 million square miles of marginal land which otherwise would have been converted to low-yield farming and livestock production.5 Further increases in the efficiency of food production systems are not only essential to meeting global nutritional needs but are also the key to halting much of the deforestation that takes place in environmentally sensitive areas with attendant wildlife habitat destruction and loss of biodiversity.Clearly the challenge of the next century is to achieve a step-change increase in the productivity of the world’s agricultural systems and in the quality and affordability of the food they produce. As agricultural supply and demand tighten government policies must prevent rising prices from imposing severe hardships on some of the developing countries. At the same time there must be adequate incentives to ensure continued investments in agricultural systems by the private sector. Increased government funding for research will be critical especially in those areas that have been neglected or underdeveloped.Many of the step-change improvements for increased productivity and food quality will come from dramatically enhanced crop production technologies. Because of their proven record in developing new agricultural technology and business systems on a global basis the world’s major agricultural chemical and genetics-based companies will certainly lead the way. Many of these companies are already undergoing the changes needed to prepare them for the opportunities and challenges of the 21st century. $9.2 Billion TOTAL Table 1. Opportunities for crop protection chemical class replacement Size Class $1.5 Billion $0.3 Billion $3.3 Billion $1.5 Billion $0.4 Billion $0.7 Billion $1.5 Billion Triazines Quaternary ammonium Organophosphates Carbamates Benzimidazoles EBDC’s Acetanilides Perceived risk issue Groundwater Accumulation Acute Toxicity Acute toxicity; estrogenic effects Acute toxicity; estrogenic effects Pest resistance Toxicity Groundwater accumulation Competition and restructuring in the crop protection industry The crop protection industry is led by a relatively small number of large and highly competitive companies.For example in 1997 the top 10 agrochemical companies accounted for approximately 80% of the $30 billion worldwide crop protection sales. The global agrochemical market is relatively mature with real growth averaging only 1.2% per year since 1990.6 In this marketplace a company’s success comes from the introduction of new products which can gain market share only if they offer sufficient customer and societal benefits to displace existing products.Reaching these attribute targets with new product offerings is increasingly difficult time consuming and costly. Industry-wide more than $125 million in total costs are accumulated by the time a new product generates its first sales and it is not uncommon for the discovery and development phase to last 8 or 9 years. The cost of bringing new products to the marketplace is further increased by ever more challenging societal demands leading to more stringent government regulatory requirements. The industry continues to undergo a good deal of volatility due to rapid changes in global economics regulations and competition especially competition from generic producers and companies with new cost-effective technology.For example generic competition over the past few years has reduced the price of chlorpyrifos chlorsulfuron isoproturon and trifluralin by 20% or more. Changes in regulations can be a problem or an opportunity. For example in the United States the Food Quality Protection Act (FQPA) passed in 1996 has mandated a review of existing pesticides. The FQPA establishes new standards for exposure levels for infants and children and places new emphasis on “estrogenic effects” and other reproductive endpoints. Such changes are threatening to cause the blanket cancellation of product registrations for broad classes of widely used crop protection products such as the organophosphate insecticides.Citing public concerns about possible neurological effects associated with long-term low-level exposure the UK Ministry of Agriculture has also announced a review of 15 organophosphate and 9 carbamate insecticides.7 A draconian move to cancel broad classes of crop protection chemicals could create a $9 billion opportunity for agrochemical producers to bring new technologies to the market (Table 1). Whether replacement will come gradually MILLENNIUM ESSAY 9 Pesticide Outlook – February 2000 MILLENNIUM ESSAY Table 2. History of consolidation in the agrochemical industry Event Year 1986 1987 1988 1988 1989 1990 1991 1992 1993 1993 1993 1994 1996 1996 1997 1998 1998 1999 Dupont buys Shell Development Corporation US ag business ICI buys Stauffer’s ag business Chevron buys PPG’s ag business Sumitomo & Chevron form Valent joint venture Dow and Eli Lilly form Dow-Elanco joint venture Ciba-Geigy buys Dr.Maag Merck Crop Protection buys Pfizer’s ag business Valent buys out Chevron’s interest in joint venture American Cyanamid buys Shell International ag business AgrEvo formed from Hoechst-Roessel and Schering ag business ICI forms Zeneca Ag Products American Home Products buys American Cyanamid Ciba-Geigy and Sandoz Crop Protection merge to form Novartis Novartis buys Merck Crop Protection Dow buys Eli Lilly’s share of Dow Elanco forming Dow AgroSciences Zeneca acquires ISK BioSciences ag businesses outside Asia Hoechst and Rhône-Poulenc proposed merger to form Aventis Agriculture Novartis and Zeneca proposed merger to form Syngenta through normal obsolescence or suddenly through government mandates remains to be seen.The desire to capitalize on new opportunities and yet at the same time to offset rising costs and compete more effectively on a global scale has precipitated a transformation in the agrochemical industry. The clear and ever accelerating trend among agrochemical companies is towards consolidation with takeovers mergers and joint ventures becoming commonplace. Table 2 lists the major consolidation events of agrochemical companies over the past 12 years.Novartis the largest company in the group with sales 1.5 times greater than its nearest competitor Monsanto was formed in March 1996 when Ciba-Geigy merged with Sandoz in a transaction valued at $30.1 billion. The 5th largest company AgrEvo was created by bringing together the agrochemical businesses of Hoechst and Schering. The 8th largest company DowElanco now known as Dow AgroSciences was created by Dow’s acquisition of Eli Lilly’s agrochemical business. One of the dramatic moves of 1998 was the announcement by American Home Products (whose American Cyanamid business was the 9th ranked agrochemical company in 1996) of its intention to purchase Monsanto (the 2nd ranked company in 1996) for $34.4 billion.8 The consolidation of Monsanto with American Home Products’ existing agrochemical business would have created the largest agrochemical company in the industry with combined crop protection sales exceeding $5 billion but the transaction ultimately failed when highly publicized negotiations between leaders of the respective companies collapsed.Another bold move in 1998 was the announced Pesticide Outlook – February 2000 10 merger between Hoechst and Rhône-Poulenc to form a new company Aventis. Aventis Agriculture will consist of three divisions Crop Science Animal Nutrition and Animal Health. Crop Science will include Hoechst/Schering’s AgrEvo and Rhône-Poulenc’s Agro former divisions with nominal annual revenues of about $4.5 billion. At the time of this writing the most recent move towards consolidation is the agreement between Novartis and AstaZeneca to merge their agricultural divisions forming yet another new company Syngenta AG.If the proposed merger is approved by antitrust regulators and shareholders Syngenta will become the world’s largest agribusiness ranking first in crop protection and third in seeds with combined 1998 revenues of approximately $7.9 billion. The trend toward consolidation can be expected to continue for the foreseeable future as companies seek partnerships that will help them reduce costs find marketing synergies between product portfolios and accelerate the pace of discovering and developing new products. The advent of agricultural biotechnology has triggered even more profound changes as leading agrochemical companies are faced with new competitive forces due to the presence of genetically engineered crops with resistance to herbicides and pests.In addition biotechnology has caused some companies to piece together vertically integrated enterprises capable of making broad product offerings and contracting at the farmer level and meeting downstream customer needs throughout the food and feed production distribution and processing supply chain. The drive is to participate in the food and feed chain from the farmer to downstream users of foods and feeds or as some have put it from the farm gate to the dinner plate. To a large extent this has developed because biotechnology makes it possible to modify crop germplasm in ways that create novel seed products which contain genetic solutions for meeting customer needs throughout the entire food and feed value chain.To speed up the discovery and deployment of useful genes companies have added new capabilities to their own internal R&D operations and many have also built alliances and/or acquired seed and biotechnology companies. The first wave of genetic solutions to enter the marketplace has included input traits such as herbicide tolerance and insect resistance as well as output traits such as high oil corn and high solids tomatoes. Monsanto has been one of the most aggressive leaders in the retooling that is occurring in the agrochemical industry. Over the past two years Monsanto’s investments have totalled approximately $8 billion according to published reports.Some major seed and technology company acquisitions include Holden’s Foundation Seeds Asgrow DeKalb Genetics Corporation Calgene AgraCetus and Plant Breeding International. Monsanto apparently will not proceed with the acquisition of Delta & Pinelands Company as originally planned. Monsanto has also built a large and complex network of partnerships with biotechnology companies that offers competitive advantages in target-based molecular design combinatorial chemistry genomics and molecular genetics. Some of these include Millennium (leading to formation of the Cereon joint venture) Ecogen ArQule InCyte Mendel and KeyGene. Monsanto also formed a joint venture with Cargill one of the world’s largest processors and distributors of food products.9 The venture will contract with farmers to grow Monsanto’s genetically engineered grain crops and also calls for each partner to contribute $100 million per year for research and development.DuPont has also invested in seeds and biotech related businesses with investments of more than $3 billion in 1997 alone.10 It recently completed the purchase of Pioneer Hi-Bred the world’s largest seed company by paying $7.7 billion for the remaining 80% it did not own. A joint venture Optimum Quality Grains LLC was formed to grow and market value-added feeds. DuPont also purchased Protein Technologies International the world’s largest producer of soy protein isolate for food applications as well as the food ingredients business of Dalgety now known as the Cereals Innovation Centre.In addition DuPont purchased Hybrinova a leading company in developing hybrid wheat varieties for Europe. DuPont recently completed the sale of its Conoco energy subsidiary in order to invest in and focus on the company’s life sciences based-businesses which include its agricultural nutrition and pharmaceutical businesses. Other leading companies such as Novartis Zeneca AgrEvo and Dow AgroSciences are also expanding and strengthening their capabilities and all have interest in seeds and biotech. The likely outcome of this wave of mergers acquisitions and alliances will be the creation of several major enterprises with large investments in R&D and world-wide marketing capabilities to meet the food and health care needs of the burgeoning world population.The impact of biotechnology Powerful new tools in biotechnology are creating new business opportunities that cross the boundaries between crop inputs and outputs. Companies are using biotechnology to synergistically link competencies in chemistry and genetics to build robust flexible and responsive technology platforms and create exciting new product offerings. These products are targeted not only at farmers but also at livestock producers processors and other end users of foods and feeds. Using a broad range of new biotechnology tools researchers are designing the next generation of crop protection chemicals and genetically engineering crops and biologicals for improved pest control yield and quality.11 These tools are already turning crops into factories to produce value-added foods feeds and industrial use products.The first genetically engineered crops to have a large presence in the marketplace have been Monsanto’s Round- Up®-tolerant soybeans cotton canola and corn as well as their Bt (Bacillus thuringiensis) insect-resistant cotton corn and potatoes. In 1998 projections called for Monsanto’s technology to be used on approximately 50 million acres world-wide 30 million in Round Up Ready® soybeans 2 million in Round Up Ready® canola 0.75 million in Round Up Ready® corn 10 million in YieldGard® corn 5 million in Round Up Ready®/Bollgard® cotton and 0.05 million in NewLeaf® potatoes.12 AgrEvo is also rapidly introducing MILLENNIUM ESSAY Liberty Link® crops that are engineered to tolerate the company’s broad spectrum herbicide glufosinate.Liberty Link® corn was grown on 700,000 acres in 1997 and could achieve 6.5 million acres in 1998.13 This is impressive progress for such an embryonic field. Projections in the industry call for genetic-based crop protection solutions to account for about 10–20% of the global $45 billion crop protection products business in 2015 with the remainder of the market going 50% to herbicides 22% to insecticides and 18% to fungicides.14 However it is important to note that in some markets biotechnology-based solutions could dominate in less than ten years.This is especially true for some insect-control markets.15 Biotechnology also offers attractive opportunities to increase substantially the yield potential of many important world crops. Most plant physiologists and molecular geneticists agree that increasing the harvest index above the 50% level already achieved in several crops is unlikely but there is significant room for improvement in the harvest index of many crops that are still below that level. Using modern genetic approaches to understand and modify crop plant architecture could lead to successes that so far have eluded classical plant breeders. Using biotechnology to elevate hybrid seed production to commercially feasible levels in crops where that has not yet been achieved by classical means is another approach for enhancing yields.In most crop species F1 hybrids are much more robust than inbred varieties showing greater resistance to pests and stresses of all kinds and generally yielding 10–20% more than inbreds. Through genetic engineering commercially efficient hybridization could be achieved in crops such as wheat and rice by improving mating properties and male sterility systems. Biotechnology also promises to change the very nature of foods and livestock feeds. DuPont has led the way in commercializing grain products with improved oil and protein characteristics. These products are now being sold by DuPont through its subsidiary Optimum Quality Grains L.L.C. Optimum® High Oil Corn (HOC) first commercialized in the early 1990s contains 7–8% oil versus the 4% typical of unimproved varieties.This boost in oil reduces feed costs by eliminating the need to add fat to the feed ration. HOC was grown on nearly 2 million acres in 1998. Over the next few years these HOC varieties will also include other value-adding traits such as increased oleic acid content and high available phosphorus. In soybeans Optimum Quality Grains is also selling products with improved oil quality. Using genetic technology to block the conversion of oleic acid (a mono-unsaturated fatty acid) to linoleic acid (a di-unsaturated fatty acid) results in a soy oil that contains more than 80% oleic acid versus standard levels of approximately 24%. The benefits of high oleic soy oil include high temperature stability for cooking health improvements (reduced saturated fat no trans fatty acids from hydrogenation) and reduced processing costs by eliminating the need for hydrogenation.Other value-adding traits such as high available phosphorus (i.e. reduced levels of phytic acid) will be introduced into the high-oleic lines. Many of the other leading agrochemical companies are working to apply genetic engineering to modify the oil 11 Pesticide Outlook – February 2000 MILLENNIUM ESSAY protein and starch of the major crops for valued-added foods feeds and industrial use products. Ideas for crop based industrial products range from modified textile fibers to fuels such as alcohol and diesel industrial lubricants industrial enzymes modified secondary compounds (sterols carotenoids etc.) polymer intermediates and novel polymers.It is safe to say that biotechnology is leading a revolution in agriculture that will bring fundamental changes in the way crops are grown how they are distributed and processed and how they are used.16 However the current debate that has been intensifying especially in Europe over the safety and the need for labelling of GMO-based products could severely slow this biotechnology revolution. Retooling the research engine In 1996 the 10 largest agrochemical companies reported aggregate R&D expenses of slightly over $2 billion which represents approximately 10% of sales and 80% of total R&D spending in the industry.17 These are substantial commitments in a slow-growth business and probably understate the actual R&D investment that is now going on.The level of R&D spending reflects the growing recognition that survival in crop protection depends on building more robust competencies for the discovery and optimization of new development candidates. It also reflects a belief that future growth depends on effectively integrating biotechnology with chemical and genetic discovery programs. Agricultural research is becoming highly interdisciplinary requiring close co-operation between chemists biologists biochemists molecular geneticists plant breeders information scientists and engineers. Few companies have all the necessary expertise internally accounting for the need to build partnerships and alliances between companies and/or academic co-operators.The success of future agricultural enterprises critically depends on retooling the chemical and genetic research competencies that drive new product discovery. Today some companies are routinely screening 100,000 compounds per year with a goal of screening a million or more in the near future. To accomplish this the industry has focused on miniaturizing and automating lead discovery screens with the goal of increasing speed and sample number as well as reducing cost and the amount of compound required. Invivo screens based on natural pest organisms are preferred because of their relevance to the marketplace and their ability to predict utility. However considerations of compound requirements and throughput rates combined with advances in the identification and production of molecular targets using the tools of biotechnology have promoted the use of in-vitro screens.The potential of such screens to replace partially or completely whole organism screens is likely to be seriously tested over the next few years. New information management systems are required for ultra-high throughput screens for evaluating and recording results and extracting the information necessary to make decisions on whether to advance particular compounds. For chemical synthesis units the key is to effectively utilize Pesticide Outlook – February 2000 12 cutting edge combinatorial chemistry technologies to generate large diverse compound libraries.This requires sophisticated data management and tracking systems. Information technology (including chemoinformatics and molecular design) also plays a critical role in guiding decisions on the acquisition of the large number of chemical libraries that are becoming increasingly available for purchase from outside vendors. The genetics research competency can broadly be considered to consist of gene discovery gene delivery (transformation) trait evaluation and variety development and breeding. Meeting the gene discovery challenge in a timely fashion is critically important to gain competitive advantage. The pace of gene discovery research is already fast but it is accelerating with each new advance in structural and functional genomics.Here again automation information technology and highly skilled people are playing critical roles in driving progress facilitating the development of new tools for determining DNA sequences for analyzing and extracting information from changes in gene expression and for analyzing proteins. Advances in the efficiency of transformation are critically needed as well as rapid miniaturized methods for evaluating transgenic organisms for desirable traits. Also needed are novel approaches to breeding that will permit the more rapid development of hybrids and elite varieties. As genetic solutions to crop protection become more of a reality companies will have to strike the appropriate balance between chemical and genetic approaches to achieve a particular market objective.Co-ordinating genetics with chemical discovery already holds significant promise for maximizing the value of herbicide leads because of the potential for developing crop tolerance via genetic strategies. Companies that succeed in rapidly discovering the site and mode of action for new herbicide leads as well as in developing systems for rapid discovery and testing of genes for herbicide tolerance will have the potential to exploit engineered herbicide tolerance. Having access to competitive germplasm will become increasingly important to execute such strategies. Outlook – technical evolution or revolution Fortunately science and technology are continuously producing new waves of technical innovation. Companies with the vision to recognize such waves early invest appropriately and ride them have the best chance of long-term success.Transforming or reinventing a company is often associated with riding these new waves of technical innovation. During the first wave in crop protection the fields of chemistry and genetics remained somewhat separate (Figure 1). The agrochemical industry relied on chemistry to create new crop protection tools while seed companies relied on genetics to create new higher yielding varieties. Both industries rode this first wave for more than 50 years by first using empirical approaches and then slowly evolving to the knowledge-based approach of the recent past. Over the last decade the fields of chemistry and genetics have rapidly converged largely catalyzed by biotechnology.accelerates. This can be seen throughout history and is already being observed today as chemogenetic product concepts are quickly moving from the drawing board to early prototypes. In part this convergence occurred because the tools of biotechnology are extremely useful for solving both chemical and genetic-based problems. Biotechnology allows one field to complement the other as in developing herbicide-tolerant crops where a chemical solution is enabled by biotechnology and genetics. This second wave of technical innovation is attracting the interest and attention of most of the major agrochemical companies. It is this current wave that is shifting existing paradigms and promises to transform companies and the entire agrobusiness food and feed chains.Whole new technology portfolios are now being developed for moving from simple to much more complex design strategies. Today biotechnologists are creating transgenic crops by incorporating single gene traits and chemists are optimizing chemicals one attribute at a time. As we move up this second wave technologies for simultaneously solving multiple complex design problems will be much more commonplace. Combinatorial approaches and informatics will play a key role in achieving these goals. The future or the third wave of technical innovation involves chemogenetics the true marriage of chemistry and genetics to yield highly sophisticated integrated systems. Here crops are engineered with a host of value-added agronomic grain quality and industrial traits in such a way that these genes can be turned on or off by chemical switches.These chemicals will be applied to crops to turn on the appropriate gene at the right time and in the right place to maximise the overall value of the crop. Thus changes in protein oil and carbohydrate composition for food feed and industrial uses could be regulated through this approach depending on the need and market value. Simple integrated systems involving a chemical switch for single gene traits are already under development. This highlights an important point as we move from one wave to the next the timeframes are compressed and the speed of innovation MILLENNIUM ESSAY Figure 1.Waves of technical innovation Will biotechnology bring about a slow steady evolution or a rapid revolution in agriculture? While the answer to this question will unfold over the next decade it is the opinion of the authors that if the public accepts this technology through the appropriate regulatory framework then a revolution is sure to occur.Such a revolution is surely needed if we are to meet the challenge of increasing Earth’s carrying capacity to 8.5 billion people by 2040 without serious food shortages and environmental consequences. Acknowledgements The authors wish to thank R.T. Giaquinta B.J. Mazur and R. Bellina for a critical reading and S. Fusca for typing. References 1. Seckler D.; Cox G. “Population Projections by the United Nations and the World Bank Zero Growth in 40 Years” Winrock Institute Arlington 1994.2. Burns G.; et al. “The New Economics of Food,” Business Week May 20 1996. 3. Brown L. R. “Struggling to Raise Cropland Productivity” in State of the World 1998 W.W. Norton & Co. New York 1998 p. 79. 4. Welch R. M.; Combs G. F.; Jr.; Duxbury J. M. “Toward a ‘Greener’ Revolution”. Issues 19 50. 5. Avery D. T. “Saving the Planet with Pesticides and Plastic” Hudson Institute Indianapolis 1995 Chapter 2 p. 29. 6. Phillips M. et al. “1997 Trading Outcome and Short-Term Outlook,” Wood Mackenzie Consultants Ltd. Agrochemical Monitor 148 3. 7. “UK Reviews OPs (organophosphates) and carbamates,” Agrow News Service May 19,1998. 13 Pesticide Outlook – February 2000 MILLENNIUM ESSAY 8.Morrow D. J. “American Home Products Buying Monsanto for $34.4 Billion,” New York Times June 2 1998 p. D 1. 9. “Monsanto/Cargill form feed and grain joint venture,” Agrow News Service May 20 1998. 10. Kilman S.; Warren S. “Old Rivals Fight for New Turf - Biotech Crops,” Wall Street Journal May 27 1998 p. B 1. 11. For further reading see the series of articles “Plant Biotechnology Food & Feed” in Science 16 July 1999 285(5426) as well as “Resistance to diseases and insects in transgenic plants progress and applications to agriculture” Shah D. M.; Rommens C. M. T.; Beachy R. N. Trends in Biotechnology 1995 13(9) 362-368. 12. Ag Biotech/Seed “Findings from the Agrobusiness Technology Tour,” Natwest Securities August 20 1997.13. op cit note 14. 14. A. E. Lund personal communication. 15. Thayer A. M. “Betting the Transgenic Farm,” C&E News April 28 1997 p. 15. 16. “Plant/Crop-Based Renewable Resources 2020 A Vision to Enhance U. S. Economic Security through Renewable Plant/Crop-Based Resource Use,” US Department of Energy GO-10097-385 September 1997. 17. McDougall J.; Mathisen F. “Agrochemical Service Update of Companies Section,” Wood Mackenzie Consultants Ltd. London November 1997 p 4. CROP PROTECTION BOOKS from the Royal Society of Chemistry Metabolic Pathways of Agrochemicals EDITORS-IN-CHIEF Terry Roberts and David Hutson Part 1 Herbicides and Plant Growth Regulators Part 2 Insecticides and Fungicides Package price (Parts 1 and 2) Chemistry and Mode of Action of Crop Protection Agents by L.G. Copping and H. G. Hewitt ISBN 0 85404 559 7 Crop Protection Agents from Nature. Natural Products and Analogues Edited by L. G. Copping ISBN 0 85404 414 0 £140.00 Pesticide Chemistry and Bioscience. The Food-Environment Challenge Edited by G. T. Brooks and T. Roberts ISBN 0 85404 709 3 £49.50 Agri-Food Quality II. Quality Management of Fruits and Vegetables Edited by M. Hagg R. Ahvenainen A-M Evers and K Tiilikkala Order to be sent to Sales and Customer Care Royal Society of Chemistry Thomas Graham House Science Park Milton Road Cambridge CB4 0WF UK. Tel +44 (0)1223 420066. Fax +44 (0)1223 423429. e-mail sales@rsc.org. Pesticide Outlook – February 2000 14 ISBN 0 85404 788 3 £69.50 ISBN 0 85404 494 9 ISBN 0 85404 499 X ISBN 0 85404 489 2 Dr. Elmo Beyer is Vice President Strategic R&D Planning within DuPont’s Agriculture and Nutrition businesses. He has responsibility for strategic planning related to new genetic- and chemicalbased technologies. With the recent merger of Pioneer Hi-Bred International Inc. these responsibilities span the seeds foods feeds biomaterials and crop protection markets. Dr. Beyer serves on DuPont’s Corporate Technology Council and the Agricultural Enterprise Strategic Steering Team. His leadership in science and technology at DuPont has helped elevate the Company to a position of global leadership in agricultural biotechnology and chemistry. Dr. Beyer joined DuPont in 1970 after receiving a Ph.D. in Plant Biochemistry from Texas A&M University. Dr. Forrest Chumley is Manager Biotechnology Partnerships & Alliances in the DuPont Agricultural Enterprise. He is responsible for meeting key technology access needs by facilitating collaboration with academics and industrial partners. Dr. Chumley joined DuPont in 1985 after completing a Ph.D. in Molecular Biology at the University of California and a postdoctoral fellowship at Cornell and M.I.T. £225.00 £250.00 £425.00 £18.50

ISSN:0956-1250    

DOI:10.1039/b006293f

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

USE OF GEOGRAPHIC INFORMATION SYSTEMS (GIS) FOR PESTICIDE EXPOSURE MODELLING Mike Neale Benno Bueeler Karl Gutbrod Martin Urban and Jose Guerra of Novartis Crop Protection discuss how GIS has been used as a tool to provide spatial data for use in exposure models in citrus in Spain simulation results. Such techniques have been used in Germany (Gutsche and Enzian 1998) to look at the possible ecomomic loss in connection with the intended application of drinking water limits for plant protection products to surface water. The main citrus-growing area in Spain around Valencia was investigated by this technique using such data as local growing practices water use rainfall figures etc. to determine the potential risk in local situations and propose appropriate risk mitigation.Introduction The use of models to predict the environmental fate of agrochemicals depends on the effects of major factors that influence environmental fate including chemical use rates chemical properties soil characteristics climatic factors and agronomic practices. Such models however are only as good as the input data that drives them. In the current EU standard risk assessment the exposure assessment for aquatic organisms is determined by using appropriate spray drift data. The Predicted Environmental Concentration or PEC values for spray drift at a range of distances are determined based on the spray drift data derived by Ganzelmeier et al. (1995) unless more appropriate data for a particular use situation or set of conditions in a specific Member State are available.In certain situations models based on measurements of the spray drift and aquatic ecotoxicity data of a compound have been developed with the inappropriate crop systems e.g. absence of data from drift trials in citrus; which have resulted in the recommendation of large aquatic buffer zones. The possible economic impact of these buffer zones has not always assessed and there is a need to determine how practical are such recommendations. Geographic Information Systems (GIS) are being used as a useful tool to provide spatial data in pesticide exposure models for environmental and ecological risk assessment. Coupling GIS with modelling enables use of geographicallybased input data as well as spatial mapping and analysis of This journal is © The Royal Society of Chemistry 2000 Pesticide Outlook – February 2000 Technical aspects The scope of GIS includes base data and its processing (Figure 1).The geographic location attributes form the key to processing geoinformation; as a simple picture one can think of data layers pinned on a globe where each pin Historical background The history of GIS (Coppock 1991) goes back to the 1960s but until the 1970s pioneers worked in isolation with very limited computer power and hardly any available geoinformation. From 1970 to 1985 progress was made as institutions like the US Bureau of Census and the US Geological Survey started processing geo-information by computer. From 1982 to 1990 hardware and software companies developed standard solutions including such examples as Intergraph and ESRI (ArcInfo).Over the last few years the GIS population has increased greatly due to the huge increase in available geo-information and the development of new GIS applications. Satellite imaging was developed initially for military purposes but in 1972 the launch of the first Landsat satellite started civil remote sensing managed today by EOSAT (Earth Observation Satellite Company). Later the French Space Agency founded SPOT (Systeme Pour l’Observation de la Terre) and presented in 1986 the first images with a resolution of 10 metres. Today many larger countries or organisations like the European Union have satellites in orbit. Usually the civil satellites are ‘poor relations’ of the military ones; while the latest generation of the former achieve spatial resolution of one to a few metres the latter are already in the range of 10 cm or less.Figure 1. How GIS works. EXPOSURE MODELLING 15 Figure 2. Mean annual precipitation in the Valencia region of Spain (1981–1990) EXPOSURE MODELLING symbolises information on a location; all layers can be analysed at the pin location. In a sense any data can become geo-information by attaching location attributes. The location and attribute information can be analysed in two forms l raster information consists of two-dimensional base elements called pixels familiar to computer users. One of the most popular forms of raster information is satellite imaging where quadratic pixels have a side-length from 30 metres down to less than 1 metre and whose data most often consist of radiation intensity of one or a few spectral windows (multispectral) l vector information comprise points lines polygones (chains of lines which can optionally describe a surface) or 3-dimensional objects like polytopes (bodies bounded by planes).The process of incorporating location information into a 2- dimensional map is called ‘projection’. To overlay multiple Figure 3. Irrigation channels used in citrus fields in the Valencia region of Spain which dry out in the summer months. Pesticide Outlook – February 2000 16 Applications of remote sensing to agriculture l low resolution (1 km) weather forecasts disease pressure models plant growth/yield models l medium resolution (100 m) overall risk assessment for larger areas (environmental behaviour of agrochemicals fertilisers) l high resolution (10 m) risk assessment for specific plots/situations l ultra-high resolution (1 m) precision agriculture geo-information the necessary steps include projecting all geo-information to a common plane with the adjustment of translation and scaling differences.Example application to citrus fruit in Spain The objective was to map citrus groves and water bodies in a test area around Valencia in Spain and based on these maps to determine the effectiveness of various pesticide risk mitigation measures such as buffer zones. Citrus in Spain Citrus cultures cover an area of 273,500 hectares in Spain i.e.about 1.5% of the country’s agricultural land. Oranges are the most common citrus fruit followed by mandarins and lemons. Citrus production in Spain is around 4,786,000 tonnes per annum with the greatest production in the Valencia region. Harvesting starts in September and lasts until the end of May depending on variety. Water use in the Valencia region Between June and September when most insecticides are applied the conditions are very dry in the Valencia region (Figure 2). Channels and drains and even the main rivers dry out. Hence for risk assessment of the potential spray drift in the summer months the smaller drains/water channels can be ignored. Farmers can irrigate approximately once a month through channels (Figure 3) supplied from six major river estuaries by opening sluice gates and flooding their fields (Figure 4); very few fields however have overflow pipes to recycle the water.For good agricultural practice label instructions of crop protection products should include a warning “Do not apply products after irrigation”. Use of satellite imagery From the Earth Satellite Corp. 3 multispectral SPOT images with pixel size 20 metres were obtained (Figure 5). Then the images were orthorectified i.e. stretched to reflect the earth’s curvature. From this areas related specifically to citrus agriculture and water were identified. The classified results from the three individual scenes Figure 4.Sluice gate opened to flood fields in the Valencia region of Spain were then mosaiced to create one file and the mosaiced image was exported to GRID format in Imagine and converted to ArcShape in ArcGRID. The water body information was then complemented by digitising 1:50,000- scale paper maps from the U.S. Geological Survey library. The vector coverage was converted into GRID format and then to ArcShape. Four sites from the GIS/Satellite map from the Valencia region were examined in more detail (Figure 6). Figure 5. EarthSat multispectral SPOT image showing agricultural land near waterways in the Valencia region of Spain. EXPOSURE MODELLING From the satellite pictures it has been possible to compute general spacial information on agricultural land near waterways i.e.distances of citrus plantations from major water bodies. Of the 380,000 acres of citrus around the Valencia region approximately 4% only is within 50 m of major water bodies while 7% is within 100 m of major water bodies. This information gives a degree of confidence to regulators that the use of certain crop protection products within a 50-m buffer zone will not present an undue risk to the environment. Conclusions The use of GIS is being developed as a very useful tool to provide spatial data for use in exposure models. By using state of the art techniques to estimate the related acreage percentages effected and to identify the economic importance of buffers strips this may well become the basis for further modelling where drift behaviour can be estimated more realistically.Specific site assessments (soil types weather conditions rainfall knowledge of watering conditions etc.) will become more and more important to maintain certain crop protection products in certain conditions. Having this information will give a degree of confidence to regulators that the use of such products with the appropriate risk mitigation e.g. buffer zones or such labelling as ‘do not 17 Pesticide Outlook – February 2000 Figure 6. ArcShape satellite images of citrus-growing areas around Valencia in Spain. The overall image of the Valencia area is shown on the left while on the right the area marked 1 is shown in more detail. Citrus (oranges) are present in >95% of the fields (shown in red).Shades of red vary according to the density of citrus crop. Many young plantations are being established (shown in light red). EXPOSURE MODELLING apply products after irrigation’ will not present an undue risk to the environment. References Coppock J. T.; Rhind D. W. The History of GIS. In D. J. Maguire M. Goodchild and D. Rhind (eds.) Geographical Information Systems. Longman Scientific & Technical (1991). Gutsche,V; Enzian S. Quantitative investigations on the geographical neighbourhood of arable land and surface water on example of the Federal states Schleswig-Holstein and Sachsen Anhalt. Nachrichtenbl.Deult.Pflanzenschutz. 50(4) S 73-78 1998 Pesticide Outlook – February 2000 18 Ganzelmeier H.; Rautmann D.; Spangenberg R.; Streloke M.; Herrmann M.; Wenzelburger H.-J.; Walter H.-F. (1995) Studies on the spray drift of plant protection products. Mitt. Biol.Bundesanst.Land- Forstwirtsch. Berlin-Dahlem Heft 305. Mike Neale is Registration Head Insecticides at Novartis in Basel Switzerland. Benno Bueeler is an IT specialist for GIS at Novartis in Basel. Kurt Gutbrod is Product Manager at Novartis in Basel. Martin Urban is Team Leader Environmental Safety Assessment at Novartis in Basel. Jose Guerra is Development Manager at Novartis Spain.

ISSN:0956-1250    

DOI:10.1039/b006296k

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

BLACK SIGATOKA Randy Ploetz of the Tropical research & Education Center at the University of Florida in the USA discusses the management of the most important disease of banana and plantain Table 1. The major exporters of banana Country Gross exports in 1997 (1000 tonnes) Introduction “During 1987 an ad hoc committee…set up by the Federal Department of Agriculture of Nigeria…recognized the outbreak of black Sigatoka in Nigeria ‘…as an ecological disaster destroying the economies of the states affected….’ The International Institute of Tropical Agriculture (IITA) has acknowledged that black Sigatoka disease is the most critical research issue for plantain and banana in Africa.” Hahn et al. (1990) Black Sigatoka is currently the most important disease of banana and plantain worldwide.The above reactions in West Africa are typical of those that occur once this destructive disease spreads to a new area. Black Sigatoka very significantly reduces the yield and quality of banana and plantain and thereby impacts the food security and economies of the affected regions. Significance of banana and plantain Banana and plantain the latter being a type of banana are among the world’s most important agricultural products. After rice wheat and milk they are the fourth most valuable food. Global output exceeded 87 million metric tonnes (MMT) in 1997 but exported fruit (mainly banana) represented only about 15% of this total. The remaining 74 MMT were produced for local consumption and marketing.Frequently the producers and end-users of the later fruit are poor subsistence farmers who utilise banana as a staple food. Black Sigatoka has a tremendous effect on subsistence production. Unfortunately most of these producers can ill afford the fungicides that are used to control this disease. Thus relatively little attention is paid to nonexported fruit in this article. Instead it focuses on the export segment of world banana production which relies heavily on the use of chemicals to control black Sigatoka. Despite their small share of global production exported bananas are major international commodities. They were valued at US$4.8 billion in 1998 and rank fourth among all exported agricultural commodities and first among all fruit crops (Anonymous).The export trades originated in tropical America in the mid-1800s and remain concentrated in this region (Table 1). The origin spread and effects of black Sigatoka Black Sigatoka was described originally in the Sigatoka This journal is © The Royal Society of Chemistry 2000 Pesticide Outlook – February 2000 DISEASE CONTROL Ecuador Costa Rica Colombia Philippines 4446 1835 1509 1255 630 602 557 Guatemala Panama Honduras Data are from FAO http://www.fao.org/default.htm Valley of Fiji in 1963. However herbarium specimens and published accounts of banana leaf diseases indicate that the disease was actually widespread in Asia by that time. Only recently has the disease spread outside this region.Black Sigatoka reached the Western Hemisphere (Honduras) in 1972 and Africa (Zambia) in 1973. By 1991 the disease had spread to much of the Americas sub-Saharan Africa and had reached the first island in the Caribbean Cuba. It is now found in most of the humid tropics in Africa the Americas and Asia and continues to spread to the few remaining areas that are free of the disease (Ploetz & Mourichon 1999). Black Sigatoka and the closely related yellow Sigatoka are the primary leaf spot diseases of banana. They are caused by two ascomycete fungi respectively Mycosphaerella fijiensis Morelet (anamorph Paracercospora fijiensis (Morelet) Deighton) and M. musicola Mulder (anamorph Pseudocercospora musae (Zimm.)) which produce similar symptoms on banana.Yellow Sigatoka has a wider distribution but black Sigatoka is more aggressive and has a wider host range; it has displaced yellow Sigatoka as the predominant leaf spot on banana in most of its range. Black Sigatoka affects plantain and banana cultivars that are resistant to yellow Sigatoka and causes significant defoliation and yield losses (Figures 1 and 2). On the Cavendish cultivars that are used by the export trades it also causes premature ripening a serious defect in exported fruit. M. fijiensis produces conidia and ascospores both of which are infective. They are formed under high moisture conditions and are dispersed by rain and irrigation water. Due to their greater abundance and small size ascospores are most important in spreading the disease within plants and plantations.Leaves are infected indirectly via stomata and the abaxial surface is the primary affected site due to the greater abundance of stomata on this part of the leaf 19 Figure 1. Initial lesions of black Sigatoka on a leaf of ‘Dwarf Cavendish’. As these lesions enlarge and coalesce they usually DISEASE CONTROL develop a water-soaked appearance. (Washington et al. 1998) (Figure 3). The unfurled new leaf referred to as the “candela” in Latin America provides an ideal microclimate for infection and it is in this structure that significant infection by ascospores occurs (Figure 4). Free moisture is required for infection by ascospores and the minimum optimum and maximum temperatures for this event are respectively 12 °C 27 °C and 36 °C.In many production areas conducive conditions occur year-round. Without the frequent use of fungicides the export trades could not control black Sigatoka and thus would be unable to produce profitable quantities of high quality fruit. The trades depend almost entirely on a single Cavendish cultivar ‘Grand Nain’. ‘Grand Nain’ produces large bunches of uniformly sized fruit and has a short stature that aids harvesting operations and makes the plant more stable than taller cultivars during tropical storms and hurricanes. Unfortunately ‘Grand Nain’ is also very susceptible to black Sigatoka. The export plantations are usually vast monocultures (Figure 5). These huge plantings lend themselves to highly mechanized harvesting and packing operations but since Figure 2.Severe black Sigatoka damage on ‘Dwarf Cavendish’ in the absence of fungicidal control measures. Pesticide Outlook – February 2000 20 Figure 3. Penetration of a banana stomata by Mycosphaerella fijiensis. Note that the germtube has arisen from an ascospore (photo R. H. Stover) they are also uniformly susceptible are also prone to devastating outbreaks of black Sigatoka (Figure 6). In order to treat such large areas with fungicides helicopters or fixed wing aircraft are used (Figure 7). This is an expensive practice since it also involves permanent landing strips facilities for mixing and loading the fungicides and the high recurring expense of the spray materials themselves.These expenses total about US$1000 per hectare per year and by the time the fruit reach a retail destination in the importing countries are responsible for 25% of the retail price. Fungicidal control of the Sigatoka leafspots Chemical control of the Sigatoka leaf spots has evolved considerably since the mid-1930s (Stover 1990). Until the mid-1970s all efforts were focused on yellow Sigatoka in the Caribbean and Central America. Bordeaux mixture the first fungicide that was used was followed by fixed coppers and the dithiocarbamates. Applications were made initially with permanent spray equipment that relied on highpressure pumps and complex underground plumbing in the plantations. Eventually aircraft replaced these permanent systems and these remain the primary means by which fungicides are applied in these settings.Petroleum oils Beginning in the late 1950s petroleum oils began to be used in Sigatoka control programs (Stover 1990). Oils were first used as adjuvants but it was soon realized that they were also somewhat effective when they were used alone. Oils possess several notable characteristics. They act as spreading and sticking agents and aid the retention and movement of fungicides on the leaf surface. Oils also assist the penetration of the leaf by systemic fungicides reduce conidium germination germ tube growth and appressorium formation and increase the pathogen’s incubation period. Finally they retard the growth and development of the pathogen within the host leaf.Figure 4. An unfurled new leaf of banana the ‘candela’. The interior of the cylinder that this leaf forms is a primary site of infection for Mycosphaerella fijiensis. (photo R. H. Stover) Saturated aromatic and non-hydrocarbon fractions of heavy and light paraffinic oils were tested first (Stover 1990). Many of these products were phytotoxic and not very effective. However as their properties became better understood effective and less damaging naphthenic and paraffinic oils were developed. Currently oils with unsulfonated residues of less than 90% aromatic contents of 12% or less and distillation ranges between 346°C and 354°C at 760 mm Hg are deemed acceptable. However in the absence of disease pressure even these refined products reduce transpiration photosynthesis and yields by 5–10% (Israeli et al.1993). Systemic fungicides Fixed copper and dithiocarbamate fungicides in oil were the standard methods of control until the first systemic fungicide benomyl (Benlate) appeared. Initially tested against yellow Sigatoka in Honduras in 1967 it was used widely by 1972. Benomyl and subsequent benzimadazoles were very effective and enabled much improved control over that provided by the dithiocarbamates. The introduction of benomyl and subsequent systemics heralded a new era of Sigatoka control (Stover 1990). Unlike the protectants systemics inhibited the development of symptoms after they first appeared. This curative action allowed the frequency of application to be reduced since it was no longer necessary to have susceptible plant surfaces continually protected from infection.About the same time that benomyl was introduced another systemic fungicide tridemorph (Calixin) was tested. It was the first sterol biosynthesis inhibitor (SBI) and remains the primary morpholine fungicide to be used against black Sigatoka. Since it was not as effective as benomyl it was not used to any great extent until benomyl resistance problems and black Sigatoka had become widespread in the 1980s. Reintroduction of protectant fungicides During the late 1970s and early 1980s new strategies were Figure 5. Large monoculture of ‘Grand Nain’ in Honduras that is typical of export plantations. DISEASE CONTROL devised to combat this disease (Stover 1990).Phytotoxicity from the oils began to cause greater concern among export producers and means by which the amount of oil that was used could be reduced were sought. At this time two new protectant fungicides a flowable formulation of mancozeb (Dithane F) and chlorothalonil (Bravo 500) were introduced that were applied in water rather than oil. Although neither product was very effective by itself during periods of high rainfall and disease pressure these fungicides were effective during drier periods when oils were assumed to cause the most damage. The new protectants were also used in resistance management programs either in alternation or in “cocktail” mixtures with systemics. During episodes of severe disease pressure cocktails of benomyl or tridemorph with mancozeb in oil and water emulsions were the preferred weapons against the Sigatoka leafspots.New systemic fungicides The first triazole fungicide propiconazole (Tilt) was introduced for use on banana in 1984 (Stover 1990). It had high post-infection activity and thus could be used on longer application intervals than were possible previously. Along with the adoption of disease forecasting measures (see below) this new fungicide allowed producers to reduce the number of applications in a plantation from as many as 45 to fewer than 20 applications per year. Propiconazole and other sterol demethylation inhibitors (DMIs) now comprise the largest group of systemic fungicides that are used on banana. Despite the large number of triazoles that have been tested against black Sigatoka [e.g.bitertanol (Baycor) cyproconzaole (Alto) difenoconazole (Score) flusilazole (Punch) hexaconazole (Anvil) metconazole (Caramba) and tebuconazole (Folicur)] propiconazole remains the most frequently used fungicide of this group (Romero & Sutton 1997). Recently the methoxyacrylate fungicide azoxystrobin (Bankit) has been shown to be effective against this disease. Azoxystrobin is at least as effective against black Sigatoka as the triazoles (Ponsioen & Doco 1999). Unfortunately its high cost limits the frequency with which it can be used. 21 Pesticide Outlook – February 2000 DISEASE CONTROL Figure 6. Permanent infrastructure such as this cableway assists harvesting and packing operations in export plantations.Fungicide resistance An unfortunate attribute of some of the most effective systemic fungicides that have been used against black Sigatoka is the ease with which their efficacy is lost. Within 2 to 3 years of the introduction of benomyl in Central America resistance began to be observed and by the late 1970s it could no longer be used effectively in many areas (Stover 1990). Although benomyl is currently not used to any great extent by the export trades mention should be made of its re-introduction for black Sigatoka control. After benomyl resistance became a major problem work in Honduras indicated that sensitive strains of M. fijiensis would displace resistant strains if benomyl use was discontinued; within 15 months only 10% of the ascospores that were assayed tolerated 10 ppm of benomyl (Stover et al.1978). In contrast Romero & Sutton (1998) reported that benomyl resistance actually remained at high levels 3 to 5 years after its use was discontinued in plantations in Costa Rica (42–100% of the strains they studied tolerated 5 ppm). The latter authors recommended that population sensitivities should be assessed before benomyl’s reintroduction was considered in a given plantation regardless of the amount of time that had transpired since its last application. Pesticide Outlook – February 2000 22 Figure 7. Airplanes are used commonly to apply fungicides in export plantations. (photo R. H. Stover) Resistance to propiconazole has developed quite differently.Reduced control with this fungicide became widely evident in Central America in the 1990s. Romero & Sutton (1997) monitored the in vitro response of singleascospore isolates to various propiconazole concentrations and observed a rapid shift towards insensitivity in three different plantations in Costa Rica. However unlike the situation with benomyl they observed wide ranges in sensitivity in each plantation and in no case was there evidence for the predominance of a highly resistant population. Although they speculated that individuals with high levels of resistance were less fit than sensitive strains the cost of resistance in M. fijiensis to this important fungicide has not been researched. Much less is known about resistance in M.fijiensis to azoxystrobin. After intensive use in a trial site in Costa Rica (>10 consecutive applications) a small population was recovered that was sufficiently insensitive to affect control (Heaney et al. 1998). Presumably significant erosion in the efficacy of this fungicide would occur if it was used in an exclusive manner in commercial plantations. Brent & Hollomon (1998) discussed the propensity of different classes of fungicides to lose effectiveness over time. They noted a wide range in the inherent risk of resistance developing in different classes. Among those that have been used against black Sigatoka the benzimidazoles were ranked as high risk the DMIs and strobilurins (e.g. azoxystrobin) moderate and chlorothalonil copper and the dithocarbamates low.They also classified the risk of resistance developing in various pathosystems. The M. fijiensis:banana system was classified as high risk since the pathogen had a short generation time sporulated abundantly and had a sexual cycle that enabled the development of new resistance phenotypes. Based on their combined fungicide and diseaserisk ratings the benomyl:black Sigatoka scenario was classified as a worse-case situation an analysis that is clearly corroborated by the short successful use of this fungicide in banana plantations. Lower but still very substantial risk was associated with the use of the DMIs and strobilurins against this disease. In order to prolong the effective life of vulnerable fungicides in high-risk situations working groups of the Fungicide Resistance Action Committee (FRAC) of the Global Crop Protection Federation (an international consortium of agrochemical producers) have created use guidelines.In general these recommendations specify that effective fungicides with different modes of action should be used on an alternating basis or in mixtures. With regard to black Sigatoka FRAC collaboration with the export companies ensures that there is industry-wide adoption of the guidelines. Once there is agreement among the respective parties on the most effective use patterns plantation managers utilise on a regional basis an integrated approach for management. Regional coordination addresses the ease with which M.fijiensis moves among plantations as well as the view that resistance management strategies would not be very effective if less than full compliance was achieved in a given area. Disease forecasting Application schedules in the plantations are now routinely determined with disease-forecast models (Stover 1990). In general these systems incorporate data on disease severity and environmental factors that are known to affect infection and disease development. The models are based on the use of oils and systemic fungicides only since protectant fungicides have no curative effect on symptom development. When these epidemiological tools were first used in Cameroon they enabled producers to control black Sigatoka with 10–14 annual applications (Stover 1990).In tropical America where control is more difficult typical schedules of 35–45 applications per year could be reduced by more than one-half when disease forecasting was first used. However increased tolerance to the DMI fungicides in Central America has recently made it necessary to again increase applications to previous frequencies of 25–40 times per year. How the introduction of azoxystrobin in black Sigatoka control programs has affected application frequencies in this region has not been reported. Outlook Undoubtedly the management of black Sigatoka represents one of the most significant and ongoing challenges in all of production agriculture. Given the dependence of the export trades on ‘Grand Nain’ it is clear that this disease will remain a severe constraint in the foreseeable future.Despite recent advances in banana breeding there are currently no resistant cultivars that could be used to replace ‘Grand Nain’. Thus fungicidal control of this disease will remain an absolute necessity in order for the trades to continue producing high quality fruit in the humid tropics. The success of these efforts will depend in no small part on the trade’s abilities to effectively manage fungicide resistance DISEASE CONTROL problems and on the development of new effective chemistries. In the absence of both of these requirements banana could again become an expensive and uncommon tropical fruit in the developed world. References Anonymous. FAOSTAT online database at http://www.fao.org/default.htm Brent K.J.; Hollomon D. W. (1998) Fungicide Resistance The Assessment of Risk. FRAC Monograph No. 2. Global Crop Protection Federation. Brussels. Hahn S.; Vuylsteke D.; Swennen R. (1990) First reactions to ABB cooking bananas distributed in southeastern Nigeria. In Fullerton R. A. and Stover R. H. (Eds.) Sigatoka Leaf Spot Diseases of Banana. INIBAP. Montpellier France. pp. 306–315. Heaney S.; Lorenz G.; Appel J.; Butler J. N.; Staub T.; Dalton I. (1998) STAR (Stobilurin Type Action and Resistance). In 1998 Status Report & Recommended Fungicide Resistance Management Guide. FRAC. Global Crop Protection Federation. Brussels pp. 19–22 Israeli Y.; Shabi E.; Slabaugh W. R. (1993) Effect of banana spray oil on banana yield in the absence of Sigatoka (Mycosphaerella sp.).Scientia Horticulturae 56 107–117. Ploetz R. C.; Mourichon X. (1999) First report of black Sigatoka in Florida. Plant Disease 83 300. Ponsioen G.; Doco H. (Eds.) (1999) MUSARAMA. vol. 12 bibliography numbers 5196 and 5224. Romero R.A.; Sutton T. B. (1997) Sensitivity of Mycosphaerella fijiensis causal agent of black Sigatoka of banana to propiconazole. Phytopathology 87 96–100. Romero R. A.; Sutton T. B. (1998) Characterization of benomyl resistance in Mycosphaerella fijiensis cause of black Sigatoka of banana in Costa Rica. Plant Disease 82 931–934. Stover R. H. (1990) Sigatoka leaf spots Thirty years of changing control strategies 1959–1989. In Fullerton R. A. and Stover R. H. (Eds.) Sigatoka Leaf Spot Diseases of Banana. INIBAP. Montpellier France. pp. 66–74. Stover R. H.; Slabaugh W. R.; Grove M. D. (1978) Effect of chlorothalonil on a severe outbreak of banana leafspot caused by benomyl tolerant Mycosphaerella fijiensis var. difformis. Phytopathology News 12 268. Washington J. R.; Cruz J.; Lopez F.; Fajardo M. (1998) Infection studies of Mycosphaerella fijiensis on banana and the control of black Sigatoka with chlorothalonil. Plant Disease 82 1185–1190. Randy Ploetz has been a research plant pathologist at the University of Florida’s Tropical Research & Education Center in Homestead since 1986. He is an authority on diseases of tropical fruit crops in particular those that affect avocado banana and mango. He has written extensively on these diseases has edited Fusarium Wilt of Banana and the Compendium of Tropical Fruit Diseases both published by APS Press and is in the midst of editing a new book Diseases of Tropical Fruit Crops that will be published later this year by CAB International. With the recent outbreak of black Sigatoka he now intends to investigate this important disease in the Homestead area. 23 Pesticide Outlook – February 2000

ISSN:0956-1250    

DOI:10.1039/b006308h

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

CONFERENCE REPORT ARE NATURAL PRODUCTS STILL A SOURCE OF INNOVATION IN CROP PROTECTION? Len Copping reports on a meeting organised in December 1999 by the Crop Protection Group of SCI with this intriguing title Why intriguing? The title clearly claims that natural products were once innovative solutions to crop protection problems but also suggests that this is now changing – or is it? Not surprisingly all the speakers and most of the audience were certain that the answer to the question in the title was a resounding yes but was this because they worked in the area and needed to convince their bosses that this was true or because they really believed it? An aspect of the meeting that was refreshing was the unrestricted contributions from the delegates to discussions.It was rare that someone did not have a question for the speakers and it was even rarer for the delegates not to have an opinion on the topic of each talk. But I still had a feeling that it was all an attempt to preach to the converted. Topics addressed included new techniques for culturing micro-organisms the use of synthetic polyamines as catalysts (interesting but is this really natural product chemistry?) and several talks on natural compounds as crop protection chemicals per se or as sources for new chemical backbones for additional chemical synthesis (pyrethroids from pyrethrum and strobilurins from strobilurin A for example). I always find these talks very interesting but sometimes worry about the attitude of (University in particular but not exclusively) researchers to natural compounds that have several effects including severe emetic reactions and broad spectrum biological activity.Acetogenins for example kill insects have some fungicidal effects are claimed to be anti-cancer agents (if you can keep them down as they have severe emetic effects) and are severely toxic to brine shrimps. Would you grind up pawpaw twigs add old washing up liquid and spray them on your allotment? Without a doubt natural products have had and will continue to have value as components of crop protection discovery but those who claim value where the risks far outweigh the potential benefit do the industry no service what so ever. It was interesting that biologicals were included in the meeting for the first time and the presenters of the data were very enthusiastic about their products but did concede that biological crop protection will never be able to achieve the level of protection in broad area crops that farmers have come to expect from chemicals.Niche high-value markets however do offer great opportunities and it was mentioned that organic farmers will use biologicals if there is a need for some input to protect the crop from attack and organic products we were told are increasing market share by as much as 20% per year. So are biologicals a ‘get rich quick’ Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 opportunity? It seems that Sumitomo and Mitsui think so with the acquisitions of Abbott Crop Protection and Biological Crop Protection respectively.Pheromones were also discussed but this turn in terms of value in strategies that can be adopted by subsistence agriculture to divert insects to catch crops to attract natural predators and surprisingly to control the parasitic weed Striga. It is truly refreshing to see a sound research team concentrating their efforts on the developing world and producing some remedies that are both effective and affordable. Molecular biology was also featured with strategies for insect and disease control discussed but surprisingly perhaps no mention of herbicide tolerant crops. Or was it surprising as the genes used by and large do not add new concepts for weed control but rather render weeds tolerant of existing products.If the isolation of genes coding for new proteins was taken in conjunction with the talk on new insect-active proteins and polypeptides there was a great deal of interest here for the delegates. The regulation of natural products was also considered and the major differences between North America and Europe were stressed. I must admit to wondering why compounds are given a ‘fast-track’ by the US-EPA just because they are natural but I also wonder why pheromones that are not applied to the crop or that are applied at very low rates and are so volatile that they blow away very quickly are so much more difficult to register in Europe. It was refreshing to hear that the Europeans are getting things together after only nine years and that a policy on natural compounds is expected any time – well within an additional nine years anyway! What was the take home message from the conference? It seems that expensive niche products will find a use in developed countries where the population has enough money to worry about the way its food is grown and pay the extra needed to support the use of such products.Molecular biology will also improve crop protection strategies and possibly allow the use of these generally less effective and usually more specific products. In the meantime natural products including natural proteins will continue to offer new modes of action new chemistries and less often new products directly for use in agriculture It is often the case that natural products are expensive to synthesise and even more costly to ferment but the use of organisms or enzymes to catalyse specific stereo-specific steps in the synthesis will render these compounds cost effective. The future is bright – the future is natural. 24

ISSN:0956-1250    

DOI:10.1039/b006309f

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

5th INTERNATIONAL CONFERENCE ON PESTS IN AGRICULTURE Brian Hicks reports on a major crop protection conference held in France at the end of 1999 Some 400 delegates attended the 5th International Conference on Pests in Agriculture held from 7–9 December 1999 by ANPP (Association Nationale de Protection des Plantes) in Montpellier. About a quarter of the delegates were from outside France and a very good simultaneous translation service was provided throughout the conference during the 75 presentations. There were also 35 posters and a trade exhibition. Proceedings are available from ANPP (Tel +33 1 43 44 89 64 Fax +33 1 43 44 29 19 E-mail anpp@anpp.asso.fr Website www.anpp.asso.fr). The conference venue was ENSA (Ecole Nationale Supérieure Agronomique) Montpellier which forms part of Agropolis International a grouping of agricultural centres in Montpellier.Some 5000 staff are employed by Agropolis of whom about 2000 are scientists. At ENSA itself there are some 900 staff including 350 scientists. Agropolis is very much orientated towards research into Mediterranean and tropical crops (http://www.agropolis.fr/). Mixed feelings about GM crop benefits Professor van Emden is more sceptical about the benefits of GM crops although he sees overall advantages when compared with approaches based on insecticides. He sees potential drawbacks in terms of yield especially when the targeted pest is absent and damage to biological control. He said there could be a “drain on total photosynthesis” diverting plant resources and was relieved to see that industry had recently admitted this in the case of a second Bt gene.Damage to biological control was also an important issue such as in relation to ladybirds. He also expects plant allelochemicals to have effects with both positive and negative interactions with GM crops. Plants can have effects on the induction of insecticide-detoxifying enzymes in insects as exemplified by the production of 2-tridecanone in tomatoes. Professor van Emden is “unconvinced about the refuge strategy” currently being adopted and commented that farms in the US and Australia were very much “experimental animals”. He also pointed out that organic growers will have to run the risk of their crops being contaminated if the new technology is to go ahead in Europe.Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 can be improved by up to 13% with less Fusarium also occurring. More beneficials are also found with Bt maize. The only product currently available for cornborer control in France is Trichogramma which has only limited effectiveness according to Monsieur Kergoat and does not control sesamia. Relating Bt crop management to risk Sue Macintosh product safety manager for AgrEvo in the Mid-West of the USA commented that Bt maize management must be related to risk as has already occurred in US programmes for pyrethroid resistance management in cotton and the boll-weevil eradication campaign. The current policy is a high-dose refuge strategy.In the longerterm a “dual-gene” approach might be adopted with both Monsanto and AgrEvo testing out these possibilities at present. In the Southern states there can be up to five generations of corn-borer in a season compared with only one in the North. In medium-risk situations 20% of crop areas are devoted to refuges increased to 40% if an insecticide spray is also used but this must not be Bt. With two different Bt proteins both expressed at a high level the refuge area could be reduced to 5%. Genetically modified crops Professor Helmut van Emden of Reading University (UK) chaired the first plenary session on genetically modified crops. There is considerable uncertainty in France regarding the future of GM crops and this was evident at the conference with many government scientists unaware of all the details and implications of them.The French supermarkets like most of their UK counterparts have been shying away from GM crops and withdrawing them from food products. Growers have also not been very receptive to GM crops and the area of Bt maize cultivated in France has fallen from 1500 hectares in 1998 to 80 ha in 1999. According to the presentation of M Giband (CIRAD Montpellier) there are some 72 GM “events” which have been approved globally some of which are the same event but from a different company. Of these 71% relate to herbicide tolerance 22% to insect resistance and 7% include both of these traits “pyramided” in the variety concerned.BT maize experiences in France Pierre Yves Kergoat (Monsanto France) reviewed some of the benefits of MON810 the company’s Bt maize effective against both cornborer Ostrinia nubilalis and sesamia Sesamia nonagrioides the latter found only in the South of France. In micro-plot trials MON810 was 97% effective but in practice in field crop situations he said this reaches 100%. There are typically two larvae of cornborer per plant but in exceptional conditions this can reach 3-4. Yield CONFERENCE REPORT 25 CONFERENCE REPORT ANPP l Background and history The French National Crop Protection Association ANPP (Association Nationale de Protection des Plantes) 6 Boulevard de la Bastille 75012 Paris organises crop protection conferences on a 3- year cycle covering plant diseases weeds and pests respectively.Its UK counterpart the British Crop Protection Council (BCPC) in contrast has a two-year cycle covering “weeds” and “pests & diseases”. ANPP was formed in April 1984 from the merger of three separate organisations involved in crop protection l COLUMA (Conférence sur la Lutte contre les Mauvaises Herbes) SFPP (Société Française de Phytiatrie et Phytopharmacie) AFIP (Association Interprofessionelle pour la Formation et Perfectionnement en Phytiatrie et Phytopharmacie) Plant Protection Service INRA Agricultural organisations and other professional bodies Industry trade and private research centres l The first COLUMA weed conference was held in 1961 the first international plant disease conference in 1985 and the first international pest conference in 1987.ANPP operates through a secretariat in Paris headed by its director Philippe Printz with two assistants. It works through twelve separate commissions which are mainly drawn from its memberships. One of these supervises the monthly crop protection journal Phytoma. The current president of ANPP is Jacques My secretary-general of the French crop protection industry trade association UIPP (Union des Industries de la Protection des Plantes) also based in Paris. His 3-year term of office comes to a close during this year. The membership of ANPP currently over 650 is on an individual basis but organisations can join as associate or benefactor members. ANPP is headed by a management board of 27 members elected for three years by the general assembly.The board is divided equally between three electoral colleges l l l One recent European introduction has been Cacyreus marshalli Butler a lepidopteran pest of pelargoniums which arrived in France three years ago having first hit the Balearic Islands in 1989 and mainland Spain in 1993. It has Quarantine pests in Europe Efforts to combat quarantine pests have formed the foundations on which the public plant protection services have been established. A session was devoted to this theme at Montpellier and the chairman commented that more recognition should be given to those in this field whose work is “rather obscure” but increasing and whose “fate is to fail”.In France the subject had its origins with an edict in 1660 on Puccinia graminis. Another landmark was a vine mildew regulation in 1870. One of the areas of concern here is the lack of funding for taxonomists although new funds are apparently to be provided. Pesticide Outlook – February 2000 26 Website developments ANPP launched its own website in January 1999 (http://www.anpp.asso.fr) which is currently attracting over 500 visitors per month. It has recently added a valuable new feature a database with a search engine (in both English and French) to enable interested parties to find research papers presented at ANPP conferences since 1994. The titles and summaries can be searched and viewed. Research papers can then be ordered for 25 French Francs per paper on average eight pages long.These are currently despatched by airmail but should be available electronically in the longer term. For those who already have copies of past conference proceedings since 1994 the search engine is a invaluable way of locating papers of interest by page number. Jacques My President of ANPP (left) and Philippe Printz Director of ANPP (right). New Name and Revised Structure ANPP is planning to increase the size of the third electoral college representing trade and industry. With biotechnology coming increasingly to the forefront of developments in crop protection ANPP is aiming to attract new members from the seed and food sectors. A name change for the association is also planned to take effect very shortly to AFPP (Association Française de Protection des Plantes) to better reflect the association’s role in plant protection in France and the French-speaking world.also recently been detected in Morocco and Portugal and there has been an eradication programme in the UK. It is not a pest in South Africa its source where there is little biological interest in it. Co-ordinating international approaches As a result of the Uruguay Round to facilitate world trade in 1994 an international sanitary and phytosanitary agreement was made with rules and procedures for plant animal and human health. A previous international quarantine agreement was signed in 1951 by 107 contracting countries. International committees with 6–8 experts consider the risks and EPPO (European and Mediterranean Plant Protection Organisation) has developed detailed procedures for Pest Risk Analysis (PRA).Inspections can be demanded before harvest by importing countries. Risk analyses are done by national laboratories but these are increasingly being co-ordinated on a European basis. There is a European warning network and warning list with the main goal being prevention. Recent European quarantine pests Philippe Reynaud of the French services gave two examples of recent quarantine pest problems. The coleopteran pest of maize Diabrotica virgifera was first detected in Belgrade in 1992 and has since spread and can no longer be effectively controlled in Europe. It has been establishing a foothold and expanding its area of infestation by 40–50 km per annum.An eradication programme was mounted after the first EU detection in Italy. The pest is very damaging to maize roots and is a major problem in the USA whence it originates. Another pest alert was put in motion in 1996 for a larger coleopteran pest Anoplophora glabripennis which was found on bonsai and other ornamental trees in New York and Chicago. It originates from China but the only bibliographies about it are in Chinese. The UK experience Richard Baker from the UK Central Science Laboratories (Sand Hutton near York) is part of a group of three fulltime staff supported by a nation-wide inspectorate which reports to the Ministry of Agriculture. He said that legislation in the UK dates back to 1877 when there were concerns about the Colorado beetle Leptinotarsa decemlineata which still remains an important target for vigilance.The UK uses a summary scheme when a rapid response is required for example following an inspection. It uses the EPPO approach which takes several months in others such as the first imports of potatoes from New Zealand. The UK deals with about 50 cases annually. EVER THOUGHT OF WRITING AN ARTICLE FOR PESTICIDE OUTLOOK? The Editor would welcome articles for inclusion in Pesticide Outlook. The aim of the journal is to publish readable up-to-date interesting articles for a wide audience which should be understandable without any assumed specialist knowledge. They should have an introduction a few sections of “meat” arranged to give a logical flow of argument and end with a conclusion summing things up and pointing the way forward.Articles can range in length from 500–2000 words. Photographs diagrams tables etc. are welcomed to increase the visual appeal of the article. Please note that contributions are refereed by two members of our Editorial Board and so publication is not guaranteed. A small honorarium is paid on publication. Please send manuscripts to Hamish Kidd Pesticide Outlook The Royal Society of Chemistry Thomas Graham House Science Park Milton Road Cambridge CB4 0WF. FAX +44 (0)1223 420247; email KIDDH@RSC.ORG. CONFERENCE REPORT Review of French efforts The Italians have done an inventory of quarantine pest problems over the period 1945-95 and M Martinez of INRA Montpellier presented his findings from a comparable French study over the period 1950–1999.He listed some 80 new quarantine insect pests from non-European sources mainly North America and Asia/Far East. Some 58% were Hemiptera (mainly aphids) with Coleoptera (18%) Lepidoptera (13%) and Diptera (6%) the other important families. The main pests have been on trees and shrubs (46.8%) and ornamentals (22.8%) with agricultural crops providing much less concern. In Italy there have been about 25% more introductions. In France the main targets for quarantine investigations have been vegetables and cut flowers followed by ornamentals and fruit. Thrip problems have shot up in recent years as have Lyromyza in aquarium plants. New products session Presentations were made on pymetrozine indoxacarb acetamiprid thiamethoxam and spinosad as well as new formulations of alphamethrin and lambda-cyhalothrin some of which had been revealed at previous conferences. Pymetrozine approval in France as a 25% WP formulation as Plenum has recently been granted for use in protected crops potatoes and hops. It has proved more effective than the current standards (such as buprofezin) for control of whitefly and aphids. The Nisso insecticide acetamiprid first approved in Japan in 1995 is being developed in Europe by Rhône-Poulenc Agro (now Aventis CropScience) as a 20% soluble powder formulation. 27 Pesticide Outlook – February 2000

ISSN:0956-1250    

DOI:10.1039/b006310j

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

FUNGICIDES NEW MODES OF ACTION OF FUNGICIDES Introduction History is littered with instances serious food shortage caused by plant disease. Yield losses due to disease vary between crops and regions and are often 10–20%. However under favourable conditions for fungal growth crop yield may be more severely reduced threatening food security and the livelihoods of farming communities. The importance of disease control has been accepted at least since the times of the Greek and Roman Empires and the various ways some more spiritual than practical that were then developed to control crop loss laid the foundations of plant protection technology and the search for new and more effective fungicides. The Ancient World knew for example that sulfur when sprayed onto cereals would protect against foliar disease but did not understand either the causes of disease or the reasons behind the success of the treatment.It is a sobering thought that the empiricism inherent in that philosophy remains a significant part of fungicide discovery today. The last 40 years however have witnessed a revolution in pesticide discovery that is particularly evident in the quest for new modes of fungicide action. Geoff Hewitt of the School of Plant Sciences at the University of Reading discusses the continuing search for new fungicidal modes of action ergosterol biosynthesis pathway (Arnold et al. 1995) and upon elegant molecular modelling. The compounds failed to progress beyond early field trials because the excellent levels of efficacy demonstrated under glasshouse conditions and high volume applications did not transfer to a field performance comparable with the standards.In contrast compounds active against ubiquitous biochemical processes may nevertheless prove useful under field conditions if other factors such as their physico-chemical properties provide a sufficient performance disparity between pathogens and non-target organisms. Mancozeb is an old but prime example of a general cell toxicant with the capability to be phytotoxic but which in practice achieves selectivity through its inability to be absorbed into the plant. Hence the product is confined to leaf surfaces where it operates as a protectant against a wide range of fungi. Mancozeb is widely used and as an established and cheap commodity it will be hard to dislodge on efficacy grounds alone.The underlying message is that mode of action studies are always qualified by field performance. New fungicides will have to comply with the increasing regulatory pressure to reduce application rates to lower fungicide toxicity to non-target organisms and to ensure environmental safety. Added to this is the clear trend towards low-input farming and the need to develop new fungicides to control the development of resistance. These are interrelated and comprise the key criteria in the validation of new modes of action. Fungicides with a specific developmental activity may comply more easily with the requirements of environmental safety and low resistance risk than those having a more general effect on fungal growth.Two examples show how a targeted approach to specificity can relate mode of action to performance characteristics Fungal growth stage Different stages of fungal developmental are characterised by particular biochemical events. Different specific modes of action may separate fungicides into those that control pathogens before entry into their host those that are effective during colonisation and those that will operate only in the final reproductive stages of development. Modes of action that target more general processes have potential for activity against all growth stages but may also lack crop selectivity or have adverse toxicology. Many fungicides fall into the first category and it is interesting that in the last six years 17 new fungicides have been announced at the Brighton Crop Protection Conference and the majority of Mode of action and performance The discovery of new modes of action that provide improved activity of fungicides against commercially important targets combined with assured environmental and public safety is a critical step in safeguarding food security.Such products must also contribute to our ability to manage the development of fungicide resistance and thereby extend the utility of established fungicides. However mode of action alone is not the key to success. Crop protection companies sell biology not chemistry and ultimately farmers buy products because they give cost-effective control of diseases like powdery mildew and not because they have new modes of action or are based on exciting new chemistry.The objective of industry is to provide its customers with products that give acceptable levels of performance and not new modes of action. Of course understanding how fungicides work is a vital part of their utility particularly for resistance management but it is overall efficacy at a competitive cost-benefit determines whether products succeed and others fail and not innovative discovery. The discovery and development by DowElanco (now Dow AgroSciences) of guanidines and amidines as competitors in the morpholine market was based upon a clear understanding of the role of the isomerase carbocation intermediate as a target site in the Pesticide Outlook – February 2000 This journal is © The Royal Society of Chemistry 2000 28 Figure 1.Carpropamid these had specific activity against pre-penetrative development stages. For example in some fungi melanin is important in the expression of pathogenicity and hence melanin synthesis inhibitors have been developed which inhibit melanin biosynthesis in the walls of appressoria the structures from which penetration of the host is effected. This is an essential and specific requirement for infection; mutants of Pyricularia oryzae (teleomorph Magnapothe grisea) that lack the ability to produce melanin are incapable of infecting rice leaf tissue. Later fungal development is independent of melanin biosynthesis and fungicides with this mode of action are therefore restricted to use as protectants.The new rice blast fungicide carpropamid (Figure 1) is ineffective in vitro other than to produce colour changes in the fungal mycelium. The compound inhibits the melanin biosynthesis pathway at two dehydroxylation steps responsible for the conversion of scylatone to 1,3,8-tetrahydroxynaphthalene and vermelone to 1,8-dihydroxynaphthalene (Thieron et al. 1998). This mode of action is distinct from that of established melanin biosynthesis inhibitors which inhibit the formation of scylatone and vermelone. The regulation of appressorium formation can however be prevented in ways others other than the inhibition of melanin biosynthesis. Quinoxyfen with an unknown mode of action is arguably one of the most intriguing of the new protectant fungicides (Figure 2).It has specific activity against powdery mildews and it too prevents appressorium formation and host penetration. The complete lack of eradicant activity and failure to inhibit mycelial growth in vitro of a broad range of fungi suggests that the target site is unique to early developmental stages. In practice the compound is effective at low rates and is mobile in the vapour phase providing uniform and long-term levels of control. Resistant isolates have been identified but have a severely reduced capacity to sporulate and are unfit. Competition with the small reservoir of established mildew left unaffected by treatment is thought to result in the maintenance of a sufficiently ‘wild-type’ population to ensure a low resistance risk.Quinoxyfen is also an excellent example of the delay that often occurs between product introduction and the definition of mode of action. A similar condition exists for the anilinopyrimidines and both are evidence to the strength of empiricism within discovery. Fungicides that inhibit spore germination germ tube development and/or host penetration may match most of the performance criteria posed for new fungicides. Because of target site specificity they are likely to be highly selective to the crop and to established fungal colonies which will remain unchallenged. This specificity may also offer an FUNGICIDES Figure 2. Quinoxyfen attractive route to increased environmental safety and acceptable toxicology.In terms of resistance management products active against specific steps in the pre-infection stage of fungal challenge may be less likely to encounter short-term resistance than eradicants since an element of the fungal population survives treatment and selection pressure is low. However the situation is unclear; the strobilurins are effective protectants but have met rapid resistance. Of course other modes of action that target different developmental stages or are active against inclusive metabolic events will continue to produce important products. The sterol biosynthesis inhibitors (SBIs) are active against ergosterol biosynthesis a feature of cell membrane development in all fungi except the Phycomycetes.The activity is the basis of their broad spectrum of use and because many SBIs are mobile within plants they can control many stages of fungal development and have protectant and eradicant uses. At high rates of application some SBIs induce host responses such as growth retardation but the group has the broadest utility of fungicides and 30 years after their discovery still commands 20% of the global market. Similarly the strobilurins are broad-spectrum products by virtue of their mode of action against the mitochondrial electron transport chain at complex III but in practice their performance segments them largely into the new and growing long-term protectant market. Structural configuration In nature biochemical processes are sensitive to the configuration of bioactive molecules such as fungicides.Whilst molecular symmetry is not an absolute factor in many reactions stereoisomerism is important where the applied fungicide exists as a mixture of configuration types arranged around one or more asymmetric atoms or chiral centres. These enantiomers may differ in their biological activities including their side effects and in cases where enantiomers have different activities and the least active can be eliminated there are theoretical opportunities for rate reductions and increased profitability. If the inactive enantiomer has adverse activity in the environment it follows that the pure product will also pose a lower risk although this remains theoretical.Metalaxyl an acylalanine for specific use against the Peronosporales was launched in 1977 as a 50:50 mixture of two enantiomers. A strategy aimed at risk reduction led to the resolution of the components and the introduction in 1996 of metalaxyl M the first enantiomeric form of any fungicide product (Figure 3; Nunninger et al. 1996). Metalaxyl M is at least as active as the original mixture but at half the application rate and the overall safety profile 29 Pesticide Outlook – February 2000 FUNGICIDES Figure 3. Metalaxyl M Figure 4. Recent chiral fungicides RPA 407213 (left); AC 382042 (centre); and iprovalicarb (right) benefits through the subsequent reduction in environmental loading and over double the rate of degradation in soil. In addition to the biological advantages that arise from resolving enantiomeric mixtures pure products may be viewed by registration authorities as having ‘reduced risk’ and speed official approval.Only 7% of all agrochemicals are sold as the active enantiomer(s) but development of the large-scale preparation of stereo-pure products will become a major factor in the commercialisation of chiral fungicides. Recent examples of chiral fungicides include an imidazolone (RPA 407213) an inhibitor of mitichondrial electron transport at the enzyme ubihydroquinone:cytochrome c oxidoreductase with activity confined to the S-enantiomer a phenoxyamide (AC 382042) with activity against the dehydratase enzymes of melanin biosynthesis and an amino acid amide carbamate (iprovalicarb) a possible inhibitor of amino acid metabolism in oomycetes both of which have two chiral centres and comprise mixtures of four and two isomers respectively (Figure 4; Mercer et al.1998; Sieverding et al. 1998). borne diseases conventional chemistry is not effective and biological antagonists may offer a possible solution. In addition the growing use of integrated methods of crop protection may encourage greater use of whole organisms to control disease especially in combination with synthetic fungicides to reduce resistance risk but as yet few products have had any commercially significant impact. The search for new modes of action Our level of understanding of the disease syndrome in terms of biochemical knowledge of fungal action and plant response does not yet permit the design of specific fungicides.For many years industry’s hope has been that synthesis from rational design will short-cut the discovery and development process. Whilst however design drives the optimisation of empirically-discovered activity it cannot claim to have been responsible for any product discovery. The objective is not only to discover a new mode of action but also to translate the activity into favourable field performance and regulatory acceptance at a competitive cost. Whilst a holistic approach may not be realistic novel sources of chemistry and techniques are becoming available that will help in the separation of probable from possible solutions. Bioactive organisms The control of plant disease by whole organisms continues to be an attractive alternative to the use of synthetic chemistry the most lucrative sources being from the genera Pseudomonas Burkholderia and Bacillus (e.g.Bacillus subtilis). At least nine fungi (e.g. Ampelomyces quisqualis) are known to have potentially useful activity. The number of biologically active agents is increasing and the technology is particularly suited to niche markets that are unable to support strong financial investment in research and to those crops where repeated applications are acceptable for example fruit. In some situations as in the control of soil- Pesticide Outlook – February 2000 30 Natural products Over the last 40 years only 24 fungicidal natural products have been commercialised (8 chemistries 16 microorganisms).Commercial products include the polyoxins blasticidin S kasugamycin mildiomycin and validamycin and most are produced by fermentation of Streptomyces spp. All have specific modes of action and since their introduction in the 1960s and 1970s resistance has become widespread. A departure from the trend is soraphen A which is isolated from Sorangium cellulosum and has activity against Oomycetes through the inhibition of acetyl-CoA carboxylase. The future for natural products is promising given that their agricultural importance as organisms and derived chemistry is estimated to be in excess of $400m in 2000 (Lisansky and Coombs 1994) that the bulk of the microbial world is uncharacterised and that less familiar sources of novelty such as the mud plains of the abyssal oceanic depths are yet to be explored.Derived chemistry Bioactive organisms operate through competition with other microorganisms in the rhizosphere and phylloplane. The basis for competitive advantage arises from the production of potent antifungal metabolites many of which are characterised and some of which have inspired the synthesis of highly successful fungicides. The strobilurins mimic the compounds strobilurin A and oudemansin A natural products with weak and transient activity against a wide range of fungi. Synthetic programmes to stabilise the molecule and increase activity led to kresoxim-methyl and azoxystrobin the first examples of this new group (Figure 5).Strobilurins inhibit electron transfer in complex III of the mitochondrial electron transport chain. Figure 5. Strobilurin fungicides kresoxim-methyl (left); azoxystrobin (right) Figure 6. Pyrrolnitrin-derived fungicides fenpiclonil (left); fludioxanil (right) The field performance is predominantly protectant with activity against the pre-penetrative developmental stages of most commercially important fungi and importantly incorporates a strong element of long-term efficacy. Redistribution in the crop is via systemic movement and a continuous mechanism of absorption and desorption from the waxy cuticular leaf surfaces mediated by the vapour phase. There is intensive competition within the class and it appears set to occupy a leading position in the fungicide market.The secondary metabolite pyrrolnitrin obtained from cultures of Pseudomonas pyrocinia is UV-unstable and although fungicidal is unsuitable as a product. Directed synthesis produced fenpiclonil (poorly systemic) and fludioxonil (non-systemic) which have broad spectrum and systemic activity with the exception of the Phycomycetes (Figure 6) used as seed treatments. Induced resistance Induced resistance or systemic acquired resistance (SAR) describes the non-phytotoxic and non-specific defence responses in plant tissue that are triggered at a distance from the site of infection. The process is distinct from the production of phytoalexins which is closely associated with the infection site. The phenomenon is well documented but poorly understood and is based upon the induction of antifungal proteins by long distance signal molecules such as salicylic acid.Use of this phenomenon in disease control has the potential advantages of providing long-lasting and very broad spectrum protection with low resistance risk that is intrinsically less challenging to the environment than conventional technology. Characteristically inducers of SAR will be inactive in vitro but possess broad protectant activity in vivo. In practice acibenzolar (Figure 7; Kessmann et al 1996) a highly mobile benzothiadiazole and a known inducer of SAR triggers activity against fungi bacteria and viruses and in many cases provides useful control but phytotoxicity most likely in the form of reduced yield potential may also be produced.The practical potential of induced responses is not yet clear. The only commercially significant product in the class Figure 7. Compounds producing induced resistance responses acibenzolar (left); probenazole (right) FUNGICIDES is probenazole which operates through the induction of fungitoxins such as a-linoleic acid and several enzymes including phenylalanine ammonia lyase and peroxidase and has specific use against P. oryzae. Genomics The identification of genes that govern particular biochemical or physiological processes offers a means to control those processes directly by genetic engineering or indirectly through the elucidation of biochemical pathways and the definition of potential sites for inhibition by synthetic fungicides.Selected biochemical processes would be both essential for fungal growth and peculiar to fungi. These are the sought-after targets for the development of new fungicides whilst natural defence mechanisms are of interest for GM disease resistant crops. l genomics and plant breeding Other than in the USA where Bt and herbicide-resistant varieties are already on the market application of the technology to plant breeding is in the early stages of development and is subject to considerable and often misdirected public scrutiny. Opportunities follow from work to define the genes responsible for the control of vital function in target fungi and their hosts. The characterisation of the encoded enzymes that govern the underlying biochemistry may indicate targets for a variety of synthetic strategies.The technology can also be used to identify sites of inhibition by fungicides of unknown mode of action. However the most powerful application of genomics in plant disease management is likely to be in the identification and manipulation of sequences that confer fungal resistance to crops (induced resistance; phytoalexin production) or that allow the overproduction of anti-fungal metabolites by competitive organisms. l genomics in lead generation In terms of lead generation the identification and validation of targets is the priority and genomics looks set to provide the key. The development of combinatorial techniques that enable access to vast libraries of compounds is already a feature of discovery in the pharmaceutical industry and their adoption in pesticide discovery ensures that the bulk of fungicide leads will continue to emerge from empirical screening.The philosophy acknowledges that empirical screening is an exercise in applied statistics; the sample size has to be large enough to include potential leads yet small enough to be screened in a realistic time-frame. The larger the sample the more leads are discovered. The strength of combinatorial chemistry is its partnership with highthroughput screens that are constructed from a knowledge of vital biochemical or physiological functions in fungal and plant-pathogen interaction driven by genomics. Armed with information about probable target sites a suitable screen and combinatorial chemistry comprehensive searches of different chemistries can be made raising the screening rate from tens of thousands annually to hundreds of thousands.31 Pesticide Outlook – February 2000 FUNGICIDES Given that the demand for food in quantity and of high quality is increasing and that crop diseases will never disappear the rejection of technologies that reduce the threat from pathogenic fungi is not an option. Currently the combination of crop variety management and fungicide use is the main means to control disease in food crops and the situation is likely to continue into the foreseeable future. In controlling disease we participate in the dynamics of trying to stabilise monocultural systems that are continuously at odds with the environment.It is to be expected that fungi will adapt to each and every weapon that the crop protection industry can manufacture and that mankind fights a battle not to win but simply to maintain an acceptable level of food security. In practice this means that synthetic fungicides having new modes of action and better performance characteristics will always be required and that those discoveries will have to be managed carefully in integrated systems of cropping that include the best of all technologies. In particular advances in genomics will grow rapidly adding a new tier of technology to crop protection a movement that is matched by the changing structure of research investment in major companies.On the basis of our present state of technology and discovery one has to be optimistic that we shall meet the challenge. References Arnold M. I.; Duratti A. D.,; Jung M.; Katz R. B.; Liebeschuetz J. W. (1995). Guanidinium and amidinium fungicides a new class of carbocation mimetic ergostrerol biosynthesis inhibitors. Pesticide Science 44 341–355. Kessmann H.; Oostendorp. M.; Ruess W.; Staub T.; Kunz W; Ryals J. (1996). Systemic activated resistance – a new technology for plant disease control. Pesticide Outlook 7(3) 10–13. Disease control in past issues Interested in disease control and fungicides? – see the following selection of articles published in Pesticide Outlook. Chemical control of rice diseases in Japan (Inoue) 1(4) 31 Fire blight in Switzerland (Rueegg) – 2(2) 16 Potato blight (Cooke) – 3(4) 28; 9(6) 22 Control of Botrytis cinerea in grapevine (Leroux) – 6(5) 13 Natural antifungal compounds (Gorris) – 6(5) 20 Azoxystrobin a systemic fungicide (Clough) – 7(4) 16 Anilinopyrimidines in Switzerland (Rueegg) – 8(3) 28 Disease control in stone fruits (Penrose) – 9(2) 13 Control of cereal eyespot fungi in France (Leroux) – 9(4) 34 Control of pecan scab (Wood) – 10(1) 12 Take-all (Yarham) – 10(2) 54 Fungicide resistance management into the next millennium (Russell) – 10(5) 213 Pesticide Outlook – February 2000 32 Lisansky S.G.; Coombs J. (1994). Developments in the market for biopesticides. Proceedings of the British Crop Protection Conference - Pests and Diseases 3 1049–1054.Mercer R. T.; Lacroix G.; Gouot M.; Latorse M. P. (1998). RPA 407213 a novel fungicide for the control of downy mildew late blight and other diseases on a range of crops. Proceedings of the British Crop Protection Conference - Pests and Diseases 2 319–326. Nunninger C.; Watson G.; Leadbitter N.; Ellgehausen H. (1996). CGA 329351 Introduction of the enantiomeric form of the fungicide metalaxyl. Proceedings of the British Crop Protection Conference - Pests and Diseases 1 41–46. Sieverding E.; Hirooka T.; Nishiguchi T.; Yamamoto Y.; Spadafora V. J.; Hasui H. (1998). AC 382042—a new rice blast fungicide. Proceedings of the British Crop Protection Conference - Pests and Diseases 2 359–366. Thieron M.; Pontzen R.; Kurahashi Y.(1998). Carpropamid a rice fungicide with two modes of action. Pflanzenschutz nachrichten Bayer 51 257–277. Further Reading G. T. Brooks and T. R. Roberts (Eds.). Pesticide Chemistry and Bioscience; the Food-Environment Challenge (1999). The Royal Society of Chemistry Cambridge. L. G. Copping and H. G. Hewitt (Eds.). Chemistry and Mode of Action of Crop Protection Agents (1998). The Royal Society of Chemistry Cambridge. H. G. Hewitt. Fungicides in Crop Protection (1998). CABI Publishing. Geoff Hewitt is a plant pathologist with over 25 years experience in the crop protection industry with a wide knowledge of global agriculture and pesticide use but with a specialisation in cereal fungicide discovery. He works as a consultant and freelance lecturer in addition to his role as short courses manager in the School of Plant Sciences The University of Reading. Books by Geoff Hewitt Chemistry and Mode of Action of Crop Protection Agents by L. G. Copping and H. G. Hewitt (ISBN 0 85404 559 7 £18.50) Available from Sales & Customer Care Department Royal Society of Chemistry Thomas Graham House Science Park Milton Road CAMBRIDGE CB4 0WF UK Tel. +44 (0)1223 432360; Fax +44 (0)1223 423429; email sales@rsc.org Fungicides in Crop Protection by H. G. Hewitt (ISBN 0851992013 £22.50) Available from CABI Publishing CAB International Wallingford OX10 8DE UK Tel +44 1491 832111; Fax +44 1491 829292; E-mail orders@cabi.org

ISSN:0956-1250    

DOI:10.1039/b006311h

出版商:RSC    

年代:2000

数据来源: RSC

摘要:

THE GM DEBATE Mary Griffin reports on a debate held by SCI the Society of Chemical Industry at the Chemical Laboratory of the University of Cambridge in the UK on 2 November 1999 blind for lack of vitamin A there could be significant potential benefit in producing crops such as rice or rape seed that include vitamin A a substance that in overdose can cause poisoning. A benefit of insect-resistant maize would be that there would be no secondary infections from Aspergillus and consequently no aflatoxin. Motion The motion for debate was “This house believes that genetically modified food can be good for the farmer good for the environment and good for you” Speaking for the motion were Professor Alan Malcolm President of the Institute of Biology and Mr David Carmichael farmer and member of the NFU Biotechnology Committee and speaking against the motion were Mr Pete Riley Friends of the Earth and Dr Len Copping specialist in herbicide physiology.Mr James Clarke Arable Technical Manager from ADAS Boxworth acted as Chairman. The debate was open to the public and had been widely publicised in the region. 119 people attended. Voting at the end was on a show of hands and showed a clear majority in support of the motion. For the motion Professor Alan Malcolm Breeding of animals and plants has been done for hundreds of years and the proportion of household income that is spent on food has dropped this century from a third to an eighth. Cheapness of food is welcome. Of course technology can be bad for example the motor car and television have led to problems but society can identify the risks and deal with them.As far as GM foods are concerned the public have lapped up such products as vegetarian cheese produced from chymosin transplanted into laboratory-based organisms and cheaper tomato paste made from lower water content tomatoes. By contrast the opposition to GM soya is attributable to British xenophobia as soya is produced overseas and the British public has not been aware that soya products are used in so many foods. However there is no difference between lecithin from GM and ordinary soya; the same applies for soya starch and protein. Modern analytical techniques are so good that this can be said with confidence. Consequently there cannot possibly be any difference between animals fed on products from GM or ordinary soya.An important question is does the public trust the government to regulate the situation? The concept that applies to decisions over GM products is that of ‘substantial equivalence’ a somewhat woolly phrase that had been devised to allow for example for the difference between two apples of the same variety. In addition to GM products that are indistinguishable it should be borne in mind that in countries where people go DEBATE Against the motion Mr Pete Riley People are sceptical about assurances given by governments and by industry and the public has been surprised that companies were so near to commercialisation of GM crops without checking the safety of the crops or the public’s reaction.GM soya and maize arrived in the supermarkets without proper consultation and it appeared that these products were being rushed to the market. Cross-pollination is inevitable as pollen can travel large distances—4 km for oilseed rape. There are many wild relatives of oil-seed rape. What makes a plant an invasive weed is not known but it appears that over the course of 10–20 years there will be a whole new generation of weeds. It is unclear who will pay for the damage but it appears likely that growing GM crops will have an effect on land values. GM crops will have to be grown to a tight regime which will require more paperwork. Consumers are now voting by avoiding products for example Unilever’s product ‘Beanfeast’ based on soya halved its sales over a 6-month period so that now the GM soya has been removed from its production.The safety of GM foods is uncertain. A recent article in The Lancet by Harry Kuiper (of the State Institute for Quality Control of Agricultural Products in Wageningen The Netherlands) has stated that the unintended effects of GM foods need to be examined. A complete halt to genetic engineering in the field should be called. This journal is © The Royal Society of Chemistry 2000 Pesticide Outlook – February 2000 Mr David Carmichael GM crops are new techniques worth trying. As a farmer I have been seeking continuously to try new techniques all the time to cut costs and am trying to be kinder to the soil.For example while Durum wheat can be grown in the south I cannot grow it in the Midlands and I need to consider new crops all the time. At present there are 85 million acres of GM crops being grown in the world implying the readiness of consumers to accept such crops. In 1997 there was a reduction in herbicide use an increase in yield of 47% and For the motion 33 DEBATE an increase in return of $29 per hectare as a result of GM crops. For example sugar beet requires £200 per hectare spent on weed control but if a GM herbicide-tolerant crop is grown only £60 per hectare needs to be spent. Last year I made a total of 36 applications of chemicals (nine applications of six different chemicals) to my beet but a glyphosate-tolerant crop would have needed only a couple of applications of glyphosate.The effect of using Bt cotton (i.e. cotton containing the Bt gene which codes for a protein toxic to certain insects) in the US was an increase in yield of 14% in 1997 and an increase in profits of $133 per hectare while in the state of Alabama there has been an 80% reduction in the use of pesticides. New crops for the future include high carotene-containing crops to save people’s eyesight. The Sugar Beet Research Association has found that there were side benefits to the use of herbicide-resistant beet weeds grow amongst the sugar beet and the aphids prefer the weeds so that no insecticide is needed. In addition the growth of ladybirds is encouraged. Finally when the weeds are killed with herbicide a mulch is produced that retains the water in the soil.Against the motion Dr Len Copping The wording of the motion has been cleverly chosen because anything CAN be good for you. The question is do the risks outweigh the benefits? In the case of foods the answer is ‘no’. Transgenic organisms are the result of unnatural selection examples being Bt maize and cotton and Roundup-Ready (glyphosate-tolerant) soya where the farmers end up being tied to the particular pesticide. Also what will happen when the foreign genes escape? There would be Roundup-Ready weeds with the Roundup-Ready crop. As far as the Bt crops are concerned there have been some advantages in the Southern US but Bt is a very specific insecticide. If there are attacks by insects that are not affected by Bt then insecticides will still be needed.As for those insects that are affected by Bt since the plants express the Bt toxin all the time then resistance will build up in the insect population. Also the fecundity of insects feeding on the crop such as ladybirds and butterfly larvae will be affected. One result of the development of resistance will be that organic farmers will lose one insecticide that they are currently permitted to use. In the case of the herbicideresistant crops the lack of surrounding weeds will mean that there would be no shelter for animals and nothing for insects to feed on meaning a reduction in biodiversity. As for checking safety in the US a variety of GM soya has been found to be allergenic and this has been spotted but would all potential problems be spotted? Of course not.The audience should vote against the motion. Questions from the floor A wide ranging series of comments and questions were then expressed from the floor many of which were answered or further explored by the speakers for and against the motion. l If a drought-resistant crop is developed or a high-protein Pesticide Outlook – February 2000 34 crop will those against GM technology deny such a crops to the people of countries like Chad? l Why should there be any problem with gene transfer in a GM crop? l Beef was declared to be safe but there turned out to be problems – isn’t it appropriate to be ultra-cautious with food? l The arguments in favour for consumers are that GM foods would be cheaper and lead to enhanced nutrition.This is not yet the case and I cannot see the benefit for the Third World l There is always a risk with any technology and the question should be whether the risk is acceptable? What is the risk and what are the consequences? Summing up Professor Malcolm said he had no difficulty in agreeing that the main debate was not scientific. He agreed with the opposer of the motion about many things. The market would decide the matter. In China there was a large acreage of GM crops being grown. In the USA 300 million Americans had been eating GM crops for 5 years which must mean they consider GM foods to be safe. Pesticide levels are important and they had dropped and the associated costs had also dropped.The risk could be calculated scientifically but there had been a problem at a psychological level in communicating the science of what was being done. Mr Riley reminded the audience of the arguments. Intensive farming squeezes the small producers. GM crops would have serious deleterious consequences for biodiversity. Many of the claims made by the proposers were flawed. Corn borers for instance do not attack the seed heads of maize plants and would not lead to secondary infections of Aspergillus and aflatoxin production. There is clear evidence that with food safety is paramount. We had BSE despite assurances from governments and scientists so why believe them now? We need to consider the world the environment and species diversity and move away from high-input farming back to sustainable agriculture if not for our sakes then for the sake of our children and our planet. 0 29 90 Results of the votes In favour Against Abstentions After the debate The debate goes on !! Dr Mary Griffin researched into the physical chemistry of milk proteins at the Institute of Food Research Reading her work on the structure and functions of caseins leading to the award of the RSC Food Chemistry Group Junior Medal in 1987. She now works in University administration continuing to teach undergraduate chemistry. She retains a keen interest in food issues. Dr Griffin has been a member of SCI for 12 years and currently sits on the Society’s Cambridge and Great Eastern Section Committee.

ISSN:0956-1250    

DOI:10.1039/b006312f

出版商:RSC    

年代:2000

数据来源: RSC