摘要:

COMPANY NEWS Aventis CropScience …..acquisition rumours continue Aventis has announced plans to sell its Aventis CropScience subsidiary following the resignation of its chief executive Alain Goddard. Proposals for the sell-off were first made in November 2000 and in July 2001 Bayer signed a letter of intent with the parent company to acquire the CropScience division. Meanwhile Schering is restructuring with emphasis on pharmaceuticals and plans selling its stake in Aventis CropScience as well as reducing its participation in the biotechnology company Metagen. …..in Japan Aventis CropScience and Shionogi are to form a crop protection chemicals joint venture in Japan. The new company owned 66% by Aventis and 34% by Shionogi will be named Aventis CropScience Shionogi having initial annual turnover of EUR 290 M.The company based in Tokyo will be headed by Jacques du Puy who is currently chief executive of Aventis CropScience Japan. Aventis CropScience Shionogi will benefit from Shionogi’s well-established distribution network throughout Japan. ….sells household insecticide division Aventis CropScience has sold its household insecticides division to Sumitomo Chemical Co Ltd in Osaka. ….eyes 2004 launch for novel widespectrum insecticide Aventis CropScience expects to launch its novel insecticide ethiprole in 2004. In Japan the product is expected to have widespread application against paddy field insects and generate annual sales of several billion Yen.….sells formetanate in North America Aventis CropScience is to sell formetanate its active ingredient for insecticides to US company Gowan. The sale includes registration documents product expertise and the Carzol and Dicarzol brands. The product will be marketed in the US and Canada by Gowan; by Gowan de Mexico in Mexico; and by Margarita Internacional elsewhere in the world. Paradigm and Bayer extend commercial partnership Paradigm Genetics Inc. and Bayer AG have announced an extension and expansion of 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. 126 Pesticide Outlook – August 2001 This journal is © The Royal Society of Chemistry 2001 their commercial partnership for herbicide discovery and development.Per the agreement the companies will collaborate on herbicide discovery for an additional 5 years with 3 years of committed funding plus a 2-year option that would extend the collaboration to October 2006. Under the terms of the contract Paradigm will receive up to $30 million including milestone payments. Paradigm will also receive success fees for all products that reach the market. DuPont discontinues Benlate DuPont Crop Protection is to discontinue the production of its fungicide benomyl and the sale of its Benlate 50 DF fungicide. Benlate will not be sold after 31 December 2001 and all trade channels are expected to cease by 2002.Benlate had global sales of $90 M in 2000. DuPont has been in litigation over the product since the early 1990s. Acquisitions and mergers ….Sumitomo Chemicals and Mitsui By March 2004 the merger of Sumitomo Chemical and Mitsui Chemicals is due to be completed. There will be seven component companies in the final structure. These will be for Petrochemicals Basic Chemicals Specialty Polymers Specialty Chemicals IT and Electronic Materials Agricultural Chemicals and Pharmaceuticals. The new company will be known as Sumitomo Mitsui Chemical Co Ltd. A joint holding company is to be established by October 2003 with Mitsui Chemicals and Sumitomo Chemical being absorbed at the end of March 2004.Kumiai–Bayer joint development Kumiai Chemical Industry has signed a license option agreement with Bayer for the novel fungicide benthiavalicarb. Kumiai is planning to make a simultaneous global launch of a range of proprietary combination formulations during 2003. The fungicide is effective against downy mildew and infectious diseases in grapes potatoes and leaf crops at doses of less than 100 g ha–1. It is safe to animals and humans and meets environmental standards. Ihara Chemical will produce the active ingredient. …Sumitomo Chemical restructuring Sumitomo Chemical is to merge its Agros Corp subsidiary into its plant protection division with effect from 1 October. Agros markets Sumitomo’s pesticide products to Japanese wholesalers and retainers and has sales of Yen 10 bn/y.It also undertakes some pesticide formulation work. …Nufarm acquires Agtrol’s fungicides Nufarm has bought Agtrol’s copper and tin based fungicides division from Philbro- Tech. The group is also negotiating the sale of its European operations to Nufarm. The fungicides division accounts for 60% of Agtrol’s $50 M turnover. Nufarm will take over its 45 employees but Philbro-Tech will retain the units and supply products to Nufarm under long term contracts. Agrochemicals account for 65% of Nufarm’s $521 M turnover but this deal represents the Australian group’s entry onto the fungicides market. Disappointing first year for internet trading Two internet traders have announced staff cuts recently triggering speculation of an uncertain future for online trading.The UK launch of Agrifirst.com due in April 2001 has been postponed “indefinitely” with all UK staff laid off although marketing in France will continue. The company conducted only some £0.95 M trade in France in its first year against an estimated total trade in supplies of £53 bn. Globalfarmers. com has cut its development team and dispensed with its editors completely. However it claims to have achieved higher trade in its launch year than Agrifirst with output now doubling each month. The company’s most popular products are Temik (aldicarb) Topik (clodinafopmethyl) and chlormequat. A new company first4 farming.com a low-cost joint venture between several suppliers and distributors is to trade soon. BASF site to close By the end of the 3rd quarter of 2002 BASF’s R&D centre at Princeton NJ is to be closed by BASF with all of the company’s agrochemicals research being carried out in Limburgerhof Germany and Research Triangle Park NC. The closure will result in the loss of around 500 jobs. The operations at Princeton were acquired by BASF in 2000 when it bought American Cyanamid. DOI 10.1039/b106284k

ISSN:0956-1250    

DOI:10.1039/b106284k

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

Hazardous and obsolete pesticides …FAO report on obsolete pesticides The UN’s Food and Agriculture Organisation released a report on 8 May 2001 declaring that millions of people and the environment are at risk from obsolete pesticides. An estimated 500,000 tonnes of old and unused pesticides that have been banned or expired are creating a danger to health in developing and transition countries the report said. According to FAO the quantities of these obsolete pesticides in Africa and the Near East are estimated at over 100,000 tonnes in Asia at over 200,000 tonnes and in Eastern Europe and the former Soviet Union at more than 200,000 tonnes. The pesticide waste which has accumulated over more than 30 years contains some of the most dangerous insecticides such as persistent organic pollutants (POPs) aldrin chlordane DDT dieldrin endrin and heptachlor that have been banned in most countries.As the pesticides deteriorate they create even more harmful by-products that can seep into nearby farm fields houses food stores and markets. The removal and destruction of pesticides is expensive with disposal costs estimated at $3 /kg or litre. Funding for disposal has so far been provided almost exclusively by governments and aid agencies. FAO called on chemical companies represented by CropLife International (previously known as Global Crop Protection Federation) to contribute urgently to the global disposal of pesticides. It also called upon its members to apply environmentally friendly Integrated Pest Management methods and to drastically reduce the use of pesticides (http://www.eis.be) ….Ethiopian pesticide stockpile CropLife International is said to be close to reaching an agreement with the UN Food and Agriculture Organization (FAO) over aid in disposing with obsolete pesticides in Ethiopia.The FAO estimates that the stockpile rose from 1500 tonnes in 1997 to about 2500 tonnes in 2001. Some reports indicate that the stockpile could be as high as 2800 tonnes. The chemicals are located at over 900 sites. It is believed that Europe. If the EU goes ahead with a radical there are 100,000-500,000 tonnes of overhaul of its subsidies system some obsolete pesticides stored around the believe production of cereals and other world.For more information on CropLife commodities could fall by up to 15-20%. International see http:/www.croplife.org Agrochemical producers are thus and page 141 of this issue of Pesticide developing strategies to cope with a Outlook. possible decline in the W European market. Outlook for agchems in EU Conditions could worsen on the European agchems market if the EU adopts a new agricultural policy with strong reductions in production subsidies. Analysts expect the market to be relatively sluggish in 2001. The market declined in 2000 and this looks likely again in 2001 with regard to value. The decline could run over into 2002. There is cautious optimism over the US agchems market in the short-term. But the European position is viewed less hopefully.The principal causes of the slowdown in Europe are low crop prices and a sharp drop in farmers’ incomes. There is no sign of any lasting recovery in crop prices at present this applying as much to the US as DOI 10.1039/b106285a REGULATORY NEWS …European chemical industry response to Rotterdam Convention The European Chemical Industry Council (Cefic) the European Crop Protection Association (ECPA) which is affiliated to Cefic and the European Association of Chemical Distributors (FECC) have started implementing a unilateral initiative to notify exports of certain hazardous chemicals and pesticides on a voluntary basis. EU legislation currently provides for notification of first exports of chemicals which are banned or severely restricted under Regulation 2455/92/EEC.The Cefic/FECC initiative is an early application of the Rotterdam Convention on Prior Informed Consent (PIC) Procedure for Certain Hazardous Chemicals and Pesticides in International Trade opened for signature in September 1998. The initiative will allow the chemical industry the European Commission and national authorities to gain experience of procedures that are not expected to become legally binding for another two years (http://www.eis.be) ….disposal in the UK A national scheme for the disposal of unwanted and obsolete pesticides is being set up under a Control of Pesticides Association (CPA)-led consortium. This is part of the package of measures accepted as an alternative to the pesticide tax.It will be similar to the disposal scheme which existed in the early 1990s. Pesticide Outlook – August 2001 127 This journal is © The Royal Society of Chemistry 2001 Integrated farming in the Netherlands The Dutch government plans to have at least 90% of its arable farmers following approved integrated growing systems by 2005. Failure to achieve the target will result in legislature to enforce the measures. Certification and control procedures are already being tested on 250 arable farms throughout the country. Pesticides are also to be discouraged by taxation of the use of active ingredients. The farming industry fears that agrochemical use on farms is to be suppressed below even “marginal return levels”.No ban on contentious pesticides in Netherlands Farmers and horticulturalists in the Netherlands will be able to use 11 controversial pesticides as usual during the 2001 growing season. The president of the court of law in the Hague rejected calls by a number of environmental organizations for these agents to be banned. The Stichting Natuur en Milieu the Zuid-Hollandse Milieufederatie and the Vereniging van Waterbedrijven had brought a lawsuit against the government to prevent use of these pesticides which they say are harmful to the environment and ground water. Zineb not in Annex 1 The European Commission has confirmed that zineb will not be included in Annex 1 under Directive 91/414/EEC Annex 1 since it is no longer being supported in its review programme.Although authorization will be revoked within 6 months the disposal storage and use of existing stocks will remain legal for 18 months from March 2001. Sweden to limit home garden use of herbicides The Swedish National Chemicals Inspectorate (KemI) has issued a proposal limiting the application of herbicides in home gardens in an effort to prevent damage to cultivated plants and to human health. KemI has expressed concern over the increasing use of glyphosate in home gardens along with other herbicides such as acetic acid dicamba and mecoprop. KemI has also proposed that only trained professionals should be allowed to use previously approved herbicides.The organisation expects to obtain a decision for the proposal not later than 2002. REGULATORY NEWS New registrations …Syngenta announces first registration for pyriftalid Syngenta has been granted marketing approval by the South Korean authorities for the herbicide pyriftalid for use in rice paddies. This is the active ingredient’s first registration. It will be used with cinosulfuron in the broad-spectrum product APIRO Ace GR. Pyriftalid is particularly effective against the grass Echinochloa. This is a difficult weed to control in rice paddies. …methoxyfenozide authorised for EUwide sale under plant health directive. The European Commission has passed a Decision accepting the conformity in principle of the dossiers it has received for detailed analysis with a view to including methoxyfenozide (RH 2485) in Annex I of Directive 91/414/EEC on the marketing of plant health products.While analysis is being carried out by the UK in order to 128 Pesticide Outlook – August 2001 decide whether the substance should be included in the list of authorised products Rohm and Haas may be granted provisional authorisation for sale of the product by Member States. This is limited to a maximum period of three years. (For further information see www.eis.be) …Syngenta receives USA registration for Callisto corn herbicide. Syngenta Crop Protection announced that its new Callisto corn herbicide has received registration from the US Environmental Protection Agency (EPA) under its reducedrisk pesticide programme.Callisto is registered as a post-emergence corn herbicide and may be applied from crop emergence. The active ingredient in Callisto is mesotrione a synthetic relative of natural herbicides produced by the Callistemon citrinus plant. Syngenta has also received approval for the sale of Callisto in Germany and Austria in late 2000 and in France and Holland in May 2001. Supermarkets ….the UK supermarket chain Tesco has approved a new potato blight fungicide for use in the production of its Nature’s Choice potatoes. The fungicide consists of a mixture of the new active ingredient zoxium and mancozeb. ….the Co-op another UK supermarket chain which is also the UK’s largest farming organisation is to ban more than 20 pesticides including so-called hormone disrupters and organophosphates from its produce. The move comes with a challenge to governments the EU the agrochemical industry and other retailers to embark on a radical rethink of pesticide safety and regulatory controls. The Co-op has drawn up a plan after consultation with Sustain— the alliance for better food and farming— and Friends of the Earth. It aims to raise flagging consumer confidence in food by encouraging more sustainable production.

ISSN:0956-1250    

DOI:10.1039/b106285a

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

Banana genome A global consortium of publically funded institutes from 11 countries meeting recently in Washington DC USA has announced that the banana is to be the first edible fruit and the first exclusively tropical crop to have its genetic code unravelled. Unlike the huge genomes of many hybrid crop plants the banana genome is relatively small and it is hoped to complete the task within 5 years. The International Network for the Improvement of Banana and Plantain (INIBAP) based at Montpellier France is the driving force behind the genome effort. INIBAP is part of the Rome-based International Plant Genetics Resources Institute (IPGRI). Other organisations in the consortium are the International Institute for Tropical Agriculture (IITA) based in Nigeria and the Institute for Genomic Research (TIGR) and organisations from Australia Belgium Brazil The Czech Republic France Germany India Mexico the UK and the USA.Half the world’s edible bananas including the Cavendish are seedless and sterile and cannot be bred at all. Instead they are propagated by taking the plantlets that appear at the base of old banana plants each year. Because they have been in evolutionary standstill for thousands of years the edible varieties are particularly vulnerable to pests and disease. As a result the banana is one of the most heavily sprayed crops in the world. It is hoped that if disease-resistant banana varieties can be developed than there could be a significant reduction in the present reliance on the use of fungicides and other pesticides.As a result instead of sequencing one of the edible varieties the consortium will sequence a wild banana from east Asia – M. acuminata from which the majority of edible bananas are descended. This species should contain useful genes that could be added to edible varieties to improve ripening and increase resistance to disease and pests. For example a gene that protects against the black Sigatoka fungus1 which destroys banana leaves and was first discovered in Honduras in the 1980s would be particularly valuable. Because interbreeding is impossible genetic modification is the only way to insert such genes into commercial varieties. 1Ploetz R. (2000). Black sigatoka disease on bananas.Pesticide Outlook 11(1) 19. Locust plagues Spring 2001 has brought with it plagues of locusts that are devastating huge areas in DOI 10.1039/b106286g North America Russia and China. In the USA an agricultural emergency has been declared in Utah where the insects have caused crop losses of more than $18 million. Russia is experiencing its worst plague for over 40 years in an area of over 70,000 hectares in Dagestan near the Caspian Sea. The insects have already destroyed 12,500 hectares of summer wheat and are threatening the winter pasture for 1.5 million sheep. In north-west China locust swarms have infested over a million hectares and the Chinese government has flown in hundreds of thousands of ducks that it is hoped will help in the control by eating the insects.There are said to be many reasons for the spread of locusts including the rising global temperature that opens up new habitats for them and in poorer countries the lack of pesticides to treat infested land. Pesticide Outlook – August 2001 129 This journal is © The Royal Society of Chemistry 2001 Insects as herbicides? The US Department of Agriculture (USDA) is looking at new natural ways to control alien weeds. Cape ivy (Delairea odorata) was introduced into the USA from South Africa in the late 1800s and soon escaped and became established in the coastal areas in California and up into Oregon. In South Africa the weed is hard to find because it has several natural enemies.Extensive collaboration between scientists at USDA and Plant Protection Research Institute in Pretoria has identified the Cape ivy gall fly (Parafreutreta regalis) and a small moth (Acrolepia sp.) that have the potential to reduce the competitiveness of the Cape ivy and thereby reducing the damage caused to willow forests. (http://www.nps.ars.usda. gov). In another study USDA-ARS scientists have introduced flea beetles (Aphthona lacertosa) to control leafy spurge (Euphorbia esula) an alien weed introduced into the USA in 1827 that now infests over 2.2 million hectares in 35 states. When these flea beetles are used in conjunction with grazing sheep very effective control is achieved. The beetles do not survive in sandy or wet areas and the search is now on to locate other biological solutions.The saltcedar tree (Tamarix spp.) is another alien tree that can grow to a height of over 10 metres and will outcompete native species increase soil salinity and divert natural streamflow. The USDA has introduced Chinese leaf beetles (Diorhabda elongata) at sites in California Texas Colorado Utah Nevada and Wyoming where the growth of the saltcedar trees has been slowly reduced allowing beneficial plant and animal species to re-establish in severely infested areas. Pesticide links to diseases …with leukemia According to a report (in Cancer Research) from a professor at Edinburgh University mothers who were exposed to propoxur and other carbamate repellents made for the control of mosquitos were ten times more likely to have a baby that developed leukaemia than those not exposed.….with Parkinson’s disease Research at the University of Rochester School of Medicine & Dentistry has shown that when rats were exposed to a combination of the paraquat and the maneb they developed symptoms like those of Parkinson’s disease. And another study (Stanford University School of Medicine) reports that a group of 496 people with Parkinson’s disease were twice as likely to have been exposed to pesticides in the home and garden as people without the disease. …with endocrine disruption A recent report from a National Toxicology Program (NTP) Panel says there is credible scientific evidence that some chemicals that are thought to disrupt the hormone system can affect bodily functions of laboratory animals at very low levels.The panel found sufficient evidence of low-level effects to recommend additional studies on bisphenol A. The report also recommends more studies on chemicals suspected of imitating or blocking male hormones including the fungicide vinclozolin. ….with premature births Researchers at the National Institute of R&D NEWS Environmental Health Sciences in Bethesda MA claim that exposure to DDT may have caused an increase in premature births in the USA during the 1960s. The conclusion is based on analysis for DDE (the breakdown product of DDT) in archived blood samples from 2380 mothers as part of the Collaborative Perinatal Project (CPP).The CPP took blood samples from 42,000 pregnant women between 1959 and 1966 and followed them and their 55,000 children for 7 years. The researchers found that the likelihood of premature birth in their sample increased with increasing DDE concentrations (Lancet 2001 358 110–114). R&D NEWS IPM in US potatoes In the US Pacific Northwest the biggest threat to potatoes is leaf roll virus transmitted by the green peach aphid (Myzus persicae). USDA-ARS workers in Wapato Washington have shown that combinations of specific aphicides and the fungus Beauveria bassiana givemore effective control than either used alone. In addition combinations of B. bassiana and Bacillus thuringiensis gave better control of the secondary pest Colorado potato beetle (Leptinotarsa decemlineata) than either product alone.Morley and NIAB announce merger talks Philip Richardson (chairman of Morley Research Centre) and John Heading (chairman of NIAB) have announced that the two organisations are engaged in talks that may lead to a merger of the two organisations. It is believed that a merger would improve the services provided to members and customers. A positive decision on the merger would lead to the formal process of merging beginning at the end of 2001 with completion expected by spring 2002. Key to cockroach resistance Steven Valles of USDA-ARS Center for Medical Agricultural and Veterinary Entomology has discovered a unique esterase bound to the membranes of German cockroach (Blatella germanica) that detoxifies certain insecticides thereby increasing their resistance to those compounds.In addition it was discovered that the German cockroach had several mutations in the kdr mechanism that made them more resistant to pyrethroid and related insecticides. Mosquito control …xanthan gum work at Purdue University has shown that xanthan gum spread on the surface of ponds and other stretches of open water gives good control of mosquito larvae without affecting associated pond life. The xanthan forms a temporary film on the surface of the water and this smothers the larvae when they return to the surface. There is a fear that the xanthan will need to be applied at too high a rate to be commer- EVER THOUGHT OF WRITING AN ARTICLE FOR PESTICIDE OUTLOOK? The Editor would welcome readable up-to-date articles on any pesticide-related topic.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 432160; email KIDDH@RSC.ORG. 130 Pesticide Outlook – August 2001 cially viable but the use of the gum as a floating carrier for insecticides where it will be prevented from sinking to the bottom of the water and associated pond-life are under way (Environmental Entomology 2001 30 388-93). …sponging livestock In South Asia where malaria-transmitting mosquitoes feed mainly on domestic animals researchers from the London School of Hygiene and Tropical Medicine have shown that sponging animals with insecticide is more effective and cheaper than indoor spraying of houses.Trials in six Afghan refugeee settlements in Pakistan have shown that the treatment reduces incidence of malarial infection by more than 90% and the cost of the sponging regime was 80% lower than that of indoor spraying. Biodegradable pellets protects sugar beet Cellulose capsules are to be used in future to treat nematodes that attack sugar beet. Wolff Cellulosics together with two German institutes has managed to incorporate Hirsutella rhossilensis and a nutrient used in the development of the fungus in biodegradable pellets.Sugar beet growers should profit from the development as they have been able to do little about the nematodes since the banning of chemical pesticides. The nematodes are infected and killed when the cellulose capsule opens and releases the microorganisms. Wolff Cellulosics is part of the Bayer group. Insecticidal properties of DE under study Diatomaceous earth (DE) is derived from phytoplankton fossils found in chalk deposits. Ground into dust the product has potential for the control of insects in stored grain in a more environmentally safe manner than conventional insecticides. DE is being studied at the Natural Resources Institute where it has been demonstrated that mixing the product with grain results in the waxy covering of infesting insects being absorbed resulting in dehydration and death.Trials in Zimbabwe have found DE to be as effective as organophosphates giving control up to 8 months. ‘Natural’ biopesticide to be developed BTG aims to hasten the development of DMDP (dihydroxymethyl-3R,4R- dihydroxypyrrolidine) a compound that protects crops against nematodes by forging an alliance with several organisations. The firm is collaborating with ECOS of Costa Rica INBio the Scottish Crop Research Institute Kew and the Royal Botanic Gardens on the project. DMDP is derived naturally from the Costa Rican tree Lonchocarpus felipei and is claimed to be systemic moving into the crops roots following foliar application. The partnership calls on the Costa Rican groups to develop DMDP in tropical crops such as banana while BTG will coordinate trials in temperate crops such as potatoes.A licensing agreement was signed between BTG and a top agrochemical company that is evaluating DMDP’s effectiveness in potatoes. About 10% of global crop losses are attributed to nematodes with an estimated $80 bn/y in cost in major crops alone. Snippets ….trials are underway in France and the USA of an algae product that is claimed to boost the resistance of crops to diseases. The active ingredient code-named GL32 is derived from a brown alga. The compound has proved effective against mildew septoria rusts and other fungal diseases. It has protected wheat for 6 to 8 weeks following application at ear stage. ….BASF’s new more curative strobilurin fungicide pyraclostrobin (F500) gives a yield boost beyond that expected solely from disease control. Its mode of action in this regard appears to be different from kresoxim-methyl. F500 appears to have a much larger effect on nitrogen reductase so the plant can assimilate more nitrogen. It also has a much stronger hormonal effect. ….Loveland Industries UK has launched a new dual-action adjuvant for use with vegetable and pea fungicides and insecticides. The product is a mix of organosilicone wetter and latex sticker which gives it properties which are particularly useful on the waxy leaves of brassicas onions and pulses.

ISSN:0956-1250    

DOI:10.1039/b106286g

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

Monsanto wins DuPont suit A decision by a federal district court has stated that DuPont’s licence to market seeds with Monsanto’s Roundup herbicidetolerant technology ended when the firm merged with Pioneer Hi-Bred International in 1999. The ruling also indicates that all sales of Roundup Ready soybean and canola seeds by Pioneer since the merger were not authorised. A new license should be obtained by Pioneer to continue offering Roundup Ready seeds. Monsanto has also entered into a series of deals to see two pending lawsuits involving Aventis CropScience over Roundup Ready and Bollgard cotton varieties. These will allow Aventis to incorporate Monsanto technologies into its FiberMax cotton. Are attitudes to GM softening? …in the UK A public opinion pole in the UK revealed that – half the population is now prepared to eat genetically modified (GM) food and the number that considered GMs unsafe fell by 10% compared with the previous year.Results suggest that public opinion against GMs is softening. The field trials programme in 2001 continues with the number of research sites unaffected by the outbreak of foot and mouth disease. The number of sites drilled in 2001 the second year of the three-year programme is 32 to spring rape 26 to sugar beet and 28 to maize. …in Australia According to a survey undertaken for the Commonwealth Government Agency Biotechnology Australia more people in Australia are willing to eat GM foods than was previously the case. The percentage of those who would eat GM foods has risen from 25% in 1999 to 32% in 2000 and is now almost 50% (http://www.biotechology.gov.au). VISIT OUR WEBSITE Have a look at the Pesticide Outlook Website on http://www.rsc.org/po DO1 10.1039/b106287p BIOTECHNOLOGY NEWS Aussie vaccine promises safe GM food Australian scientists claim to have developed a vaccine to make plants immune to viruses and enable genetic modification of food in a way that may be more acceptable to the public. Like human vaccines the vaccine activates plant defence mechanisms to knock out diseases before they take hold. It works by silencing an existing gene rather than by inserting a foreign gene. It is hoped to increase yields of major crops by up to 30%.It could be used to produce non-browning bananas caffeine-free coffee and other examples without altering the protein structure of the plants. The technology which is about to be used in trial crops involves inserting a small incomplete piece of virus RNA into plant DNA (post-transcriptional gene silencing with intron-spliced ‘hairpin RNA’ (ihpRNA)). This allows the plant to produce double-stranded RNA known as ‘hairpin RNA’ (hpRNA). The presence of the hpRNA causes the plant to activate its defence mechanism degrading the hpRNA but also ensuring that the plant is primed to protect itself in the event of an invasion by the same virus. This results in immunity to the virus which can be passed down through plant generations.The process can also target the cell’s own RNA to make the plant think that it is a virus and silence genes. The government Commonwealth Scientific and Industrial Research Organisation (CSIRO) team has already used the technique to develop potatoes resistant to potato leaf roll virus. (For more information contact nick.goldie@nap.csiro.au). Genes to control the glassywinged sharpshooter? ….Californian grape growers are very concerned about the threat to the industry from the glassy-winged sharpshooter (Homalodisca coagulata) – a sap sucking insect that transmits Pierce’s disease – a bacterial disease caused by Xylella Pesticide Outlook – August 2001 131 This journal is © The Royal Society of Chemistry 2001 fastidiosa that invades the plants xylem leading to death.….workers at the University of Florida have patented synthetic genes that are closely related to genes found in silkworm larvae that produce a protein that kills bacteria and fungi and has been shown to be effective against the Pierce’s disease organism. Work is now in progress to introduce this gene into elite vine germplasm as a means of making vines resistant to the disease. ….Demegen has granted a non-exclusive licence to ProfiGen for the purpose of studying the utility of antimicrobial (lytic) peptides on plant variety improvements for the grape industry. The goal of the research is to find solutions to important diseases affecting the grape industry including Pierce’s Disease (http://www.demegen.com). GM crops require more (or less) pesticide? ….according to a recent study Monsanto’s GM Roundup Ready soybeans require more herbicide applications in the US than conventional soybeans. A growing number of weeds are becoming resistant to glyphosate the main ingredient of Roundup herbicide. A study had shown that on average 11.4% more herbicide was used on Roundup Ready soybeans than on conventional types. But Monsanto and Roundup Ready growers say the study is misleading and designed to support groups that are against GM foods. ….according to the Centre for Agriculture and the Environment in the Netherlands the cultivation of genetically modified soybean will lead to an average reduction of 10% in the use of chemical pesticides over a period of 3 years. GM strains are said to have better resistance to certain plant diseases. In the US around half the soybean crops are genetically modified.

ISSN:0956-1250    

DOI:10.1039/b106287p

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

WATER PROTECTING WATER Steve Higginbotham of Aventis describes the finding of the recent Cherwell study which highlighted the need for on-farm best practice in handling crop protection products practice yard activities and tank filling processes were responsible for a considerable amount of the local surface water contamination. Sprayer filling poor empty package management and machinery maintenance were the main culprits. l When pouring glugging from containers and small splashes accounted for a number of spilt droplets which individually looked insignificant. But each drop of active ingredient can contain up to half a gram of active material. l Leaking equipment and dripping nozzles also contribute. One small spillage in the study contained 1.2 grams of active material.l Discarded container seals can be coated with a gram of active material there were at least 40 containers opened during this study! l Upturned containers may indicate they are empty but the rinsate leaking from these contributed more than a third of a gram of active material (Figure 1). In total 7 grams of active product were spilt on the farm yard and found its way into the river. These figures appear to be completely insignificant but because of the stringency of the permitted level of pesticides in water it would require 70,000,000 litres of water to dilute these few grams to the drinking water requirement! Or enough water to fill 35,000 large trailed sprayers. Despite the importance of these minor amounts of active material other studies have shown there is a potential for much greater contamination For example l the sprayer sump contents even after internal washings can contain 25 grams of product l the outside of a sprayer can be coated with 10 grams of chemical after a few hours of work this level will increased every time the sprayer is used if left uncleaned Introduction The quality of UK drinking water is of a high standard but the array of pollutants that must be removed or severely reduced is astounding.They include for example heavy metals bacteria organic materials industrial pollutants nitrates lead aluminium and pesticides. All these are controlled in the production of drinking water with pesticides being strictly regulated at 0.1 part per billion* or the equivalent of 1 gram of active product in 10 million litres of water.However water companies do achieve the required quality standards through constant monitoring treatment and high investment. There is also a high cost to the crop protection industry as it invests in emission control systems that alleviate the problem at the point of production. But recent studies have demonstrated that many pesticides that contaminate rivers and streams do so from their use on farms. Drinking water is derived from a number of sources including rivers reservoirs and groundwater and can at times contain trace amounts of pesticides. To understand the routes and mechanisms by which pesticides reach these waters Aventis CropScience heavily invested in a number of studies in the UK France and Germany.The study in Germany showed that only 20% of the pesticide contamination of the Dammbac river was due to field sources such as field surface runoff or drain flow. While in the UK the Cherwell study which defined the importance of the various spray related operations that take place in the farm yard attributed 45% of the contamination of the headwaters of the Cherwell (Oxfordshire UK) to drainage from the farm yard. In France the importance of field surface run off in areas of high rain fall was demonstrated. It was to reduce these trace amounts of pesticides that the proposed pesticide tax was originally designed. The crop protection industry through its association has agreed with Government to implement a pesticide stewardship package that will address this area.It is therefore critical that the farming industry puts into practice the lessons learnt from these and other studies and helps to meet the aims of the stewardship package and negate the necessity of this tax. The Cherwell Study During the autumn application of a residual herbicide to 40 hectares of winter wheat the study found that the common- *0.1 ppb is in effect a surrogate zero and is not based on either the health public or the environmental risk of individual compounds 132 Pesticide Outlook – August 2001 This journal is © The Royal Society of Chemistry 2001 Prevention All is not doom and gloom. At Dammbac a 70% reduction of farm yard contamination was achieved through sprayer maintenance (replacing dripping nozzles etc) and the addition of a clean-water tank and a brush to allow the outside of the sprayer to be washed in the field.In the UK study a reduction from the farm yard of nearly 95% was achieved by some simple management changes. So what can be done? l Have a plan and the equipment to deal with spills and DOI 10.1039/b106289c Figure 1. Upturned ‘empty’ containers with rinsate leaking – a source of potential water contamination. drips they will happen. Use inert material such as cat litter to absorb small spills (Figure 2). l Do not wash spills into drains or leave to dry to be washed in later when it rains! l Prevent glugging; even small splashes can significantly contaminate water.Remember that most neighboring farms will be doing the same job at the same time! l If feasible fill sprayer in the field but well away from ponds and streams. l Clean empty containers well reseal and replace in boxes in an upright position to await disposal. l Put seals and lids in cardboard packaging not on the ground. l Wash the sprayer in the field not the yard and store undercover. l Do not store empty container outside. All spray operators should examine their current practices and make sure they are doing all they can to prevent pesticides. Future outlook The Cherwell study was the first in the UK to document the importance of the farm yard as a site for contamination. It has formed the bases of a number of projects that aim to reduce this point source contamination.For example l the Environment Agency and the Soil Survey Reach Centre are both assessing the feasibility and effectiveness of biobeds with the hope that these will provide a safe mixing and filling area on the farm (they have proved successful in Sweden); l machinery manufacturers are redesigning their equipment to improve in-field washing capabilities; Figure 2. Cat litter and other inert material which can be used to absorb spills and drips. WATER l crop protection manufactures are reassessing their package designs. Some may argue that rivers and streams do not need to be as clean as drinking water and that such care is not required. However legislation is getting tougher for example the recent Water Framework Directive provides the water industry the opportunity to lobby regulators legislators and European Commissioners to request severe restrictions on a number of widely used pesticides.If we as the farming industry do not adopt best practice and ignore the Crop Protection Association’s pesticide stewardship initiative we will in the future not only have a pesticide tax but also risk the loss of a number of commonly used herbicides. The result will not only be an increased cost for all in the industry but will result in a severe reduction of product choice leading in turn to an increase in a number of difficult to control weeds. Reference Higginbotham S.; Jones R. L.; Gatzweiler E.; Mason P. J. Point source pesticide contamination quantification and practical solutions. Proceedings of the Brighton Crop Protection Conference (Weeds) 1999 681. Steve Higginbotham has been Stewardship Manager for Aventis CropScience for a number of years and has been directly involved in research to understand better how pesticides find their way to surface water. He chairs the industry IPU (isoproturon) stewardship group and sits on the steering committee for the Environment Agency’s project “Development of a Design Manual for Agricultural Pesticide Handling and Washdown Areas” which aims to produce a cost-effective solution to pesticide contamination from farmyards. Pesticide Outlook – August 2001 133

ISSN:0956-1250    

DOI:10.1039/b106289c

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

BIOPESTICIDES Development Harpin is a protein produced in nature by certain bacterial plant pathogens. It was discovered by Zhong-Min Wei PhD and his colleagues at Cornell University (Wei et al. 1992) and shown to be an acidic heat-stable glycine-rich extracellular protein consisting of 403 amino acid residues (no cysteine) with a molecular weight of about 40 kilodaltons. EDEN Bioscience has further studied the harpin protein and developed the commercial product Messenger® at its research and production facility in Bothell WA USA. Messenger® received approval in April 2000 from the Environmental Protection Agency (EPA) as a biochemical pesticide in Toxicity Category IV (a designation reserved for materials with the lowest hazard potential) with the EPAminimum 4-hour restricted entry interval requirement for field workers.HARPIN Janis Jones from EDEN Bioscience describes a new biopesticide which activates natural plant defence and growth systems Figure 1. Messenger® mode of action. A. Messenger is sprayed onto the plant. B. Harpin protein the active ingredient in Messenger® is recognised by receptors. C. The plant initiates and amplifies a set of complex signalling pathways causing natural gene expression. D. This natural process results in activation of plant defence systems increased nutrient uptake and photosynthesis improving crop yield and quality. DOI 10.1039/b106934a Mode of action (Figure 1) When harpin is applied to plants it activates a plant’s natural growth and defence mechanisms.It binds to plant receptors initiating a set of complex signaling pathways activating a well-defined series of systemic acquired resistance (SAR) genes inducing the jasmonic acid/ethylene dependent pathway and eliciting plant growth-related systems. These responses protect plants against a wide variety of pests on multiple crops while at the same time improving growth crop yield and quality. In field response trails on a wide variety of crops including wheat rice citrus cotton pepper and cucurbit Researchers at EDEN Bioscience and Cornell University have demonstrated that harpin has an ability to improve growth as evidenced by one or more of the following l increased photosynthesis l increased nutrient uptake l increased biomass l increased root development l increased seed germination l earlier flowering l improved fruit development l earlier fruit maturation Full response normally occurs within 3–5 days after application.Resulting effects may last for several weeks or throughout the growing season depending on the crop. The National Aeronautics and Space Administration (NASA) have confirmed these growth aspects during a wheat study in a highly controlled environment. 134 Pesticide Outlook – August 2001 This journal is © The Royal Society of Chemistry 2001 Eden BioScience receives award Eden BioScience Corp. has received a Presidential Green Chemistry Challenge Award (Small Business Category) for its technical innovation in the development of harpin technology.These awards are given annually through the EPA Office of Pollution Prevention and Toxics to recognize organizations and individuals that are successfully researching developing and implementing outstanding green chemical technologies. The latter are defined as chemical products and manufacturing processes that reduce or eliminate the use or generation of hazardous substances. The award was presented at the National Academy of Sciences by Stephen L. Johnson EPA Assistant Administrator for Prevention Pesticides and Toxic Substances during the fifth National Green Chemistry and Engineering Conference. This is only the third time an agricultural product company has won the award. Formulation The harpin formulation Messenger® is a water-soluble granular powder that is topically applied either independently or in conjunction with traditional chemical pesticides.Once applied Messenger® degrades rapidly and leaves no detectable residue on plants or in the soil and degrades rapidly in the environment; there is therefore no risk of contamination of ground or surface water. In addition harpin does not alter the plant’s DNA. Resistance Unlike traditional chemical pesticides harpin does not kill or otherwise adversely affect pests or pathogens and hence it does not exert the selection pressure that promotes the development of resistance in pest populations thus reducing the likelihood of resistance or cross-resistance development. Harpin is ideally suited to controlling pests that have developed resistance to conventional chemical treatments and to being used as a partner with highly pest-specific lower risk products.Crop uses The harpin formulation Messenger® has been extensively tested in more than 1000 field trials on more than 40 crop groupings plus turf and ornamentals throughout the world. It has been shown to be effective on a wide variety of economically important crops such as cotton wheat cucumber citrus tobacco strawberry tomato and peppers. Messenger® has demonstrated effective control of viral plant diseases for which there are currently no chemical controls. Notable examples include tobacco and cucumber mosaic viruses in tomato and pepper tobacco mosaic virus PESTICIDE BEHAVIOUR IN SOILS AND WATER For the first time this year’s BCPC Conference – Weeds 2001 will include a special interest symposium with the above title.This will run concurrently with the main conference from 13-15 November 2001 at the Hilton Brighton Metropole Hotel Brighton UK. Over the 3 days platform sessions will cover sorption and mobility degradation quantitative aspects risk management and environmental exposure and risk assessment. There will also be a poster programme linked to the platform sessions. For further information BCPC Symposium Secretariat 5 Maidstone Buildings News Bankside London SE1 1GN UK. Tel +44 (0)20 7940 5555; Fax +44 (0)20 7940 5577; email conference@bcpc.org BIOPESTICIDES Harpin technology for the Third World Eden BioSciences has unveiled a program to make Messenger® available to less-developed countries.It will be made available in the first instance to small-scale farmers in Ethiopia and Kenya. Within a year the project will be expanded to other African and Eastern European countries that apply to Eden for inclusion in the project. Representatives from Eden recently gave a half-day presentation on the Subsistence Farming Project to an audience which included some 20 ministers of agriculture from Eastern European and African nations. in tobacco and beet curly-top virus in peppers. Messenger®-treated tomato plants also exhibit reduced galling (root nodules) “tolerance” to root-knot nematodes and/or increased volume and grade of marketable fruit. Additional benefits in Messenger®-treated tobacco include a “tolerance” to cyst nematodes.It has also demonstrated effective management of other soil-borne pathogens such as Fusarium spp. in tomato cucumber strawberry and wheat. Use in IPM programmes Messenger®’s broad spectrum of control ease of use and compatibility with established Integrated Pest Mangement (IPM) practices make it an ideal product for IPM programs. It can be used throughout the growing season as a crop production tool that induces disease resistance and insect repellence while at the same time promoting optimal plant health. It does not disrupt the natural or introduced populations of beneficial predators and parasites that are often an integral component of IPM. For further information on EDEN Bioscience and Messenger® see http://www.edenbio.com References and further reading den Hond F. (1998) Systemic Acquired Resistance. Pesticide Outlook 9(2) 18. Kessmann H. (1996) Systemic Activated Resistance. Pesticide Outlook 7(3) 10. Ryals et al. (1996) Systemic Acquired Resistance. The Plant Cell 8 1809–1819. Staswick P. E.; Lehman C. C. (1999) Jasmonic acid-signaled response in plants Induced plant defences against pathogens and herbivores. APS Press. Wei Z.; et al. (1992) Elicitor of the hypersensitive response produced by the plant pathogen Erwinia amylovora. Science 257 1–132. Pesticide Outlook – August 2001 135

ISSN:0956-1250    

DOI:10.1039/b106934a

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

VIEWPOINT BUTTERFLIES AND BIOTECH A CAUTIONARY PRINCIPLE James S. McLaren1 from Inverizon International Inc. in the USA gives his views on a recent controversy challenges for the Monarch butterfly including logging the winter habitats spraying insecticides removing milkweeds (since these weeds are noxious to grazing cattle) and that physical killer better known as the car windscreen. Longterm population fluctuations are not well quantified but estimates of migratory populations range from 500 million to over a billion and the over-winter numbers have been projected to be 50–200 million in various years (Taylor 1999). Typically crop protection chemicals are used throughout the Corn Belt in order to save valuable crops from the ravages of pests and diseases.The use of such chemicals is regulated by official rules on the types of chemicals that may be applied and on the quantities of residue that may be allowed in the grains (EPA 2001). Despite such safeguards certain activist groups often complain that the practice of spraying protective chemicals is not acceptable—largely based on theoretical problems relating to food safety and environmental issues. Incidentally no scientific studies could be found relating to the impact of such pesticide applications on Monarch butterfly larvae or on adult populations. For many years a large amount of scientific effort was expended on finding alternative solutions. Part of the need for alternatives was that some crop pests are difficult to control by external sprays because they bore into the crop.If these pests are not controlled then yield can be reduced. Moreover remnants of these pests (larval carcasses or fungal hyphae or “natural” pest-derived chemicals) are themselves present in the harvested crop as “foreign” material. It was reasoned that having an enhanced internal defense mechanism would protect crops against such pests Background Each Spring as the sun begins to warm the fertile soils of the vast American Mid-West there is a stirring down in Mexico. Those Monarch butterflies (Danaus plexippus) (Figure 1) that survived the over-winter period by clinging in dense populations to oyamel trees in specific locations within the Sierra Madre mountains take flight and begin to journey northwards.Using the angle of incident sunlight as a guide each Monarch butterfly travels many miles lays eggs and dies within about 6 weeks. The underside of milkweed (Asclepias syriaca) leaves are the preferred site for Monarch egg laying. After hatching the caterpillars destroy the leaf by eating it for food and to ingest the milkweed-derived cardenolide toxins which accumulate in their bodies and act as a chemical defense against being eaten by birds. The larvae then pass through a metamorphosis in the pupal state to emerge as butterflies about 4 weeks later. During the course of the summer and over the span of 3–5 generations the journey can be as long as 3000 miles up through the Mid-West and into southern Canada. Later in the year the migration will turn south and the greatgreat-grandoffspring of a Monarch that left in the previous Spring will arrive back in the Mexican over-winter habitats completing the cycle for each genetic line within the population.Nature contains many harsh conditions that limit the survival rate including weather storms fungal pathogens parasites and many predators such as birds rodents and venomous spiders. Humans have added a few additional 1 Inverizon International Inc. Chesterfield Missouri 63017 USA. Figure 1. Monarch butterfly larva (above) (photo courtesy of USDA-ARS) and adult (right). 136 Pesticide Outlook – August 2001 This journal is © The Royal Society of Chemistry 2001 DOI 10.1039/b106288n improve feed and food safety and may also lead to decreased external chemical applications which should address the concerns of the environmental activists groups.Biotechnology to the rescue In the 1980s crop biotechnology became a viable new tool to enhance plant breeding and was considered a success because genetic changes could be made in very specific and known ways for traits of interest (McLaren 1998). Among the ideas first tried was the concept that natural protein toxins could be expressed in crops to elevate the endogenous protection mechanisms. Hundreds of Bacillus thuringiensis (Bt) insecticidal endotoxins were known and various forms of the Bt bacteria had been applied to food crops for many years especially as an insecticide in situations where organic culture was practiced.Several Bt genes were selected and cloned on the basis that they encoded protein toxins with high levels of activity against Lepidoptera larvae. In particular it was found the Cry1A(b) protein from the associated gene was active against a major pest of maize or corn (Zea mays) called European Corn Borer (Ostrinia nubilalis; Lepidoptera Pyralidae) (ECB). Following full regulatory approvals several Bt transgenic events are being used successfully in US commercial maize and cotton crops (McLaren 1998). Over the past 5 years the increase in area for commercial Bt maize has been substantial and has reached a current level of around 7 million hectares per year (Figure 2). Due to the ECB infestation distribution at economically threshold levels potentially only about 10–12 million hectares of the total 32 million hectares of US maize can benefit from ECB control.Therefore Bt maize has already been widely adopted on over 60% of the area that can benefit from use of this particular trait or on around 20–25% of the total US maize area. The future commercial area is expected to vary in response to the extent of ECB infestations combined with geographical and temporal variations in intensity and severity of damage to the crop. It should be noted that within the ECB infestation areas Figure 2. Trend for commercial Bt maize area grown in the USA. VIEWPOINT the benefits of Bt maize are now considered to be severalfold. First the crop is effectively protected from ECB damage both from tunnels in the stalk and from larvae boring into the cob.The incremental yield returns range from zero to over 2000 kg/ha depending on the conditions of each particular infestation. With fewer ECB in the maize there is less chance of having dried larvae enter the food processing system—although dead these contaminating worms contain DNA and proteins that are essentially from a “foreign” species are not regulated by any agency and have never been tested as allergens or as chemical additives in the US nor in Europe. A further benefit is that fewer larval tunnels also mean less entry holes for secondary pathogens. Consequently in some situations Bt maize has resulted in a decrease in the level of mycotoxin in the grain because of less fungal infection (Munkvold 1999).Mycotoxins are known natural chemical toxins with very potent activity—toxicity occurs with concentrations in the parts per billion to low parts per million. Whenever mycotoxins can be removed from the grain then feed and food safety is improved. The US government provides advisory warnings and maximum tolerance limits depending on the type of mycotoxin present and expected use of the grain (USDA-NCCES 1994). Biotechnology attacked In recent years an ideological polarization has developed around the concept of agricultural biotechnology. On one hand there are those who believe biotechnology brings many benefits and that it should be given a chance to prove itself as an innovative platform for improvement in the world food situation (both quantity and quality) and for the production of renewable resources in an environmentally acceptable manner.On the other hand there are those that believe biotechnology is a high risk venture with little to offer human progress. Within this already tense and polarized atmosphere a single publication concerning the Monarch butterfly acted as a lightening bolt that created unprecedented reactions and fierce accusations on both sides of the biotech debate. In May 1999 a preliminary “short scientific correspondence” was published in the journal Nature with the title “Transgenic pollen harms monarch larvae” (Losey at al 1999). For reasons best known to themselves Cornell University where the laboratory tests were done also put out a press release entitled “Toxic pollen from widely planted genetically modified corn can kill monarch butterflies Cornell study shows”.Of course the preliminary report did not really evaluate butterflies but rather a certain pre-metamorphic larval state—which is not just a semantic distinction but a real biological difference especially in relation to Bt activity. Also the preliminary report and press release were not exactly scientific breakthrough news—it is difficult to understand why anyone would expect lepidopteran larvae that are exposed to Bt to survive? After all it has been known for decades that the Bt natural endotoxin will kill such larvae. It could be suggested that this experiment was analogous to declaring water to be toxic— based on an experiment that confirmed exposure to many Pesticide Outlook – August 2001 137 VIEWPOINT gallons within a short time period can kill humans.Moreover the Nature report has received considerable criticism purely on the scientific merit of arriving at premature conclusions based on insufficient data (Berenbaum 2001; Shelton and Roush 1999). Two years and $5 million later The outcome of the initial hot debate was that a massive scientific effort was undertaken between 1999 and 2001. The pro-Bt side set out to prove that Bt was beneficial and not the end of the world nor the demise of the Monarch butterfly. The anti-Bt organizations were attempting to find any real evidence that the Monarch butterfly was in peril due to the use of transgenic Bt maize.The US and Canadian governments also set up research programs independently to determine the practical implication of the Bt maize situation. While it is difficult to calculate a precise figure an estimate of the activity undertaken times the duration of work times an average research cost number suggests that at least $3 million was expended in research and government actions on Monarch projects during this time. We estimate that an additional $1–2 million was spent by companies attempting to manage the issue and by anti-organizations in keeping the issue at the forefront of public concern. The main “public domain” scientific investigators included Dr D. Calvin Pennsylvania State University Dr G. Dively University of Maryland Dr.J. Foster University of Nebraska Dr. R. Hellmich USDA-ARS Iowa State University Dr. L. Lewis USDA-ARS Iowa State University Dr. J. Pleasants Iowa State University Dr. M. Sears University of Guelph Dr. C. Taylor University of Kansas Dr. J. Wyman Michigan State University. Results from these US (MBRS 1999) and Canadian (Sears et al 2000) scientists are reviewed below. The experiments that were completed covered a number of different scientific aspects however taken as a whole the main goal was to determine the overall impact of Bt maize on the Monarch butterfly under practical field conditions. Of course it is important to define “impact” and for the purposes of this paper it is taken as Impact = Effect � Exposure � Probability where Effect = f (type of toxicity (hazard) unit activity) Exposure = f (dose duration) Probability = f (frequency spatial/geographical occurrence event presence) In the case of Bt the type of toxicity is that the Cry protein binds to specific insect gut receptors leading to reduced larval growth and death at higher concentrations.The unit activity (LD50) for various pure Cry protein types is known however the main implicated carrier in the Monarch butterfly case is Bt pollen grains. Thus unit activity is complicated by the fact that Bt expression varies between transgenic events and Bt is present at different levels in the pollen grains of different events. For example Table 1 shows that while the levels of Bt in pollen grains are low the range in quantity of Bt protein may vary by over 25-fold.Thus the unit activity of Bt maize pollen will vary considerably 138 Pesticide Outlook – August 2001 Table 1. The amount of Cry protein typically reported for various Bt maize events that are in commercial use (adapted from Sears 2000; EPARAD 2001). Protein Event Company Amount in pollen mg/g dry wt ~0.4 ~0.09 0.09–0.33 1.4–2.4 Cry9C Cry1A(b) Cry1A(b) Cry1A(b) Aventis Monsanto Novartis Novartis CBH-351 MON-810 Bt-11 Bt-176 and the single designation “Bt corn” is technically meaningless in this respect. In laboratory studies (Sears et al 2000) Bt maize pollen from Bt-176 showed an increase in larval mortality rates when present at 541 grains/cm2 on the leaves fed.At 133 grains/cm2 no effect was observed on larval mortality. Bt maize pollen from Bt-11 and MON-810 events showed no effect on larval survival up to rates of 600 grains/cm2 and had a reported No Observable Effect Concentration (NOEC) at 150 grains/cm2 (EPA-RAD 2001). Since we know that Bt pollen at some level will be toxic to lepidopteran larvae then exposure becomes a major factor in determining the practical impact. In reality it is the amount of pollen present and available to the growing larvae in the field that impacts the outcome rather than the result of a confined feeding in a laboratory study. Much of the hard work done over the past two summers by many scientists throughout the North American maize growing regions has been to determine what level of pollen is present on the milkweed leaves that Monarch larvae feed on.Individual results varied to a small extent and are impacted by factors such as prevailing wind direction. However over many experiments and as a common result it is clear that maize pollen does not travel any significant distance. Maize pollen is relatively heavy and has a large particle size (~100 microns) and therefore tends to fall down from the tassels – as anyone who has grown corn knows the female silks can be a meter below the upper tassel level. Typical results (MBRS 1999; Sears et al. 2000; EPARAD 2001) show that at the edge of a corn field the amount of pollen falling on a surface (e.g. the upper surface of a milkweed leaf) is in the range of 6–78 grains/cm2.At a distance of 1m outside the corn field the measured levels of pollen were 5–28 grains/cm2 and at 5–10 m outside the field the levels are 0–1.4 grains/cm2. The probability that pollen exceeds the NOEC of 150 grains/cm2 is zero at 2m from the edge of a corn field based on measured levels of collected pollen. Further aspects of dose and duration are l Rain and wind removes pollen grains from the surface of milkweed leaves making actual concentration likely to be lower than that measured on frequently sampled “collection” surfaces. l The majority (>85%) of Monarch butterflies lay their eggs on the underside of the leaves. Even the low levels of pollen that potentially could be on a milkweed adjacent to a corn field would be on the upper surface of the leaf.Eventually the larvae eat their way through the leaf and potentially could be exposed—but they are then larger and less likely to be affected by low dose levels. The third main aspect of impact was probability and involves frequency distribution and overlap. In this respect we need to explore these factors for Monarch larvae and Bt pollen. The location of milkweed plants in habitats adjacent to corn fields has also been evaluated and it has been found that a small number of milkweeds may be found in corn fields. The majority of milkweeds are found in meadows and conservations areas – although these are removed from grazed grassland due to the milkweed chemical toxins being noxious to animals.It has been found that a significant number of milkweeds are present in roadsides and in Iowa up to 40% of these may be adjacent to corn fields and a 25% portion of these may lie within 3 metres of the field edge. Another major factor is temporal distribution of events. Does the developmental stage of pollen shed in Bt maize coincide with the laying and hatching of Monarch larvae. Pollen shed in maize occurs in a relatively narrow window and is driven by accumulated temperature. Egg laying by Monarchs occurs several times (each generation) and may be primarily driven by solar angle. In phenological modeling studies and in actual field measurements (EPA-RAD 2001) it has been concluded that the timing of maximum pollen shed does not overlap with the major Monarch egg laying periods in the main maize growing regions.During the period of these Monarch studies the question of impact on other species was also raised. The impact of Bt pollen on the Black Swallowtail butterfly (Papilio polyxenes) was evaluated due to the high potential risk since this species is common in the Corn Belt. Laboratory and field trials using the MON-810 event in the Pioneer 34R07 hybrid showed that no negative impact occurred to this species from Bt pollen (Wraight et al. 2000). In conclusion we can summarize the results discussed here as follows l Bt can be toxic to Monarch larvae when laboratory exposure levels are high. l In practice Bt pollen does move beyond a few metres from a corn field.l Levels of Bt pollen measured on milkweed leaves are well below effect levels. l Monarch larvae hatch and feed on the underside of milkweed leaves. l Some (<10%) of milkweed plants could be in a location where pollen is present. l Monarch egg laying and pollen shed do not appear to have a tight overlap. The cautionary lesson Millions of dollars spent on research thousands of scientific hours taken up even more spent on questionable debate opportunities lost on alternative useful research government agencies attention diverted whole new sets of rules VIEWPOINT invented and all for what? To prove biotechnology is right or wrong? As we evaluate the learning from the Monarch situation and reflect on what happened and what did not happen it should be stated that undertaking research to evaluate the safety of new technology is imperative.Without such evaluations and accompanying regulatory policies the world would fall apart very quickly. The key lesson then is not that research had not been done. Much research had indeed been done before the products were launched and the results had been reviewed by the appropriate agencies. Nor is it that more research was required – when additional data is needed then that is appropriate and the agencies do make calls for additional data. The real concern here relates to the underlying cause of the additional research that was required. It appears that at least in the case of agricultural biotechnology scientific information can be swept aside and government agencies arm-wrestled into submission.While the underlying activist organizations often represent a minority opinion in these cases we have learned the power that headlines may have in causing public opinion to move irrespective of the scientific evidence. Consider that over 1000 press stories were written on the negative effects of biotechnology on the Monarch butterfly between early 1999 and end-2000. When the additional scientific results showed overwhelming evidence that no negative effects occur in practice how many press stories were run? It is difficult to find more that three. Scare-mongering seems to be a very one-sided affair. These activist organizations who promoted the supposed Bt-based ill-health of the Monarch butterfly did not have any data nor real evidence.These are ideological groups that believe technology has not had a positive impact on the environment nor contributed to an improved and comfortable lifestyle. When the scientific evidence was presented in greater detail it became obvious that the negative connotations were false. In fact some scientists who have independently evaluated the situation have suggested that Bt maize may actually have considerable benefits for the Monarch butterfly (Pimentel and Raven 2000). The cautionary principle that has been demonstrated by the beautiful Monarch butterfly has little to do with saving species or spending money on needed research and appropriate investigations. It has everything to do with why certain research is forced on the community who demands the research and the fact that in a growing number of incidences those demands are not based on any factual evidence.The requirement for good science should not be obscured by the GM debate (Hails 2000). Beyond the illegal destruction of experimental property and valuable research we are on the verge of an inquisition where scientific principle is in danger of being degraded. What would be gained and how would the world benefit by losing fundamental thinking data-based evaluations and sciencebased regulations? The summer sun is high in the Mid-western sky the Bt corn fields are looking healthy and the Monarch butterflies are evident on their great migratory journey.Pesticide Outlook – August 2001 139 VIEWPOINT References Berenbaum M. R. (2001) Interpreting the scientific literature. Differences in the scientific and lay communities. Plant Physiology 125 509–512 EPA (2001) US Environmental Protection Agency. The Federal Insecticide Fungicide and Rodenticide Act (FIFRA) as amended by The Food Quality Protection Act (FQPA) of 1996. The Federal Register or the rules and regulations site at www.epa.gov/opppsps1/fqpa/ EPA-RAD (2001) Bt Plant-Pesticides Biopesticides Registration Action Document. US Environmental Protection Agency. Hails R.S. (2000) Genetically modified plants – the debate continues. Trends in Ecology & Evolution 15,14-18. Loosey J.; Rayor L.; Carter M. (1999) Transgenic pollen harms Monarch larvae.Nature 399 214. MBRS (1999) Monarch Butterfly Research Symposia held in Chicago and in Atlanta. Personal notes taken by the author from the scientific presentations made by the investigating scientists mentioned in the text. McLaren J. S. (1998) The success of transgenic crops in the USA. Pesticide Outlook 9(6) 36–41. Munkvold G. P.; Hellmich R. L.; Rice L. G. (1999) Comparison of fumonisin concentrations in kernels of transgenic Bt maize hybrids and nontransgenic hybrids. Plant Disease 83 130–138. Pimentel D. S.; Raven P. H. (2000) Bt corn pollen impacts on nontarget lepidoptera Assessment of effects in nature. Proceedings of the National Academy of Sciences 97 8198–8199. CELEBRATING 50 YEARS AT EPPO 2001 is the 50th anniversary of EPPO – the Regional Plant Protection Organization for the Euro-Mediterranean region.It was created in 1951 by the common will of 15 European countries which faced with a great many difficulties after World War II felt that they would be more efficient in fighting together against the introduced Colorado beetle (Leptinotarsa decemlineata). At the beginning EPPO’s activities were mainly targeted at plant quarantine on how to prevent introduction of dangerous pests and avoid their dissemination (e.g. potato cyst nematodes Hyphantria cunea Synchytrium endobioticum). But rapidly activities extended to plant protection in general including plant protection products. Today 43 countries are members of EPPO – Kyrgyzstan was added as the 43rd member in April 2000.Its partners are the National Plant Protection Organizations i.e. the official services which are responsible for plant health in each country. The technical work of EPPO is done by two working parties reflecting the two main fields of activity plant quarantine and plant protection products and by more than 15 panels of experts. A Secretariat of 12 persons based in Paris is in charge of facilitating the work of the experts by preparing documents and organizing meetings. The EPPO Secretariat also organizes two Conferences per year on topical subjects related to plant health. Exchange of information within the Organization is an important task. Numerous books brochures journals 1 OEPP/EPPO (1999) EPPO Standard PP 1/213(1).Resistance Risk Analysis. Bulletin OEPP/EPPO Bulletin 29 325-347 140 Pesticide Outlook – August 2001 Sears M. K.; Stanley-Horn D. E.; Mattila H. R. (2000) Preliminary report on the ecological impact of Bt corn pollen on the Monarch butterfly in Ontario. Plant Health and Production Division Canadian Food Inspection Agency. Shelton A. M.; Roush R. T. (1999) False reports and the ears of men. Nature Biotechnology 17 832. Taylor O. R. (1999) Monarch butterflies Population dynamics and the potential impact of add-on mortality. Monarch Butterfly Research Symposium Chicago. USDA-NCCES (1994) Understanding and Coping with Effects of Mycotoxins in Livestock Feed and Forage. US Department of Agriculture North Carolina Cooperative Extension Service N.C.State University Raleigh. Electronic publication DRO-29 at www.ces.ncsu.edu/drought/dro-29.html Wraight C. L.; Zangerl A. R.; Carroll M. J.; Berenbaum M. R. (2000) Absence of toxicity of Bacillus thuringiensis pollen to black swallowtails under field conditions. Proceedings of the National Academy of Sciences 97 7700–7703. Dr James McLaren is Founder and President of Inverizon® International Inc a consulting firm that specializes in the management of science new technology development and emerging markets. and software are prepared by the EPPO Secretariat. The results of EPPO’s work are recommendations which are now considered at international level as ‘regional standards’. EPPO recommendations are not compulsory in contrast with EU Directives. In discussions the emphasis is essentially put on scientific principles. From this point of view EPPO can be seen as a forum for free and scientific discussion sometimes preparing political discussions which take place in other fora. A recent example of this work is the development of an international standard on resistance risk analysis recommended for use in the evaluation and registration of plant protection products1. As part of its 50th anniversary celebrations EPPO organised a special conference entitled ‘Plant Health Today’ on 16–18 May 2001 in Angers France. This conference presented a comprehensive view of EPPO’s work in the field of plant quarantine and plant protection products in the past present and future. The proceedings will appear in EPPO Bulletin 31(3). Also the regular Council session in September 2001 will be preceded by a celebratory session and a Web-based exhibition on the history of EPPO its current work and future plans. EPPO is based at 1 Rue le Nôtre 75016 Paris and can be contacted on email hq@eppo.fr or viewed on the internet at http://www.eppo.org. A review of EPPO activities can be found in Pesticide Outlook 1999 10(6) 238.

ISSN:0956-1250    

DOI:10.1039/b106288n

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

INDUSTRY ASSOCIATION CROPLIFE INTERNATIONAL values which lie behind this recent name change CropLife International is the new name for the worldwide federation representing the plant science industry. The former Global Crop Protection Federation unveiled its new identity during its annual meeting in Brussels Belgium in June. The new name signifies a fundamental change in the industry’s attitudes and values including the development of more communications-oriented behavior an increased awareness and sensitivity to societal issues and greater emphasis on stewardship programmes and marketplace conduct. The new name is the fruit of two years’ teamwork creative questioning strategic thinking and concerted action on the part of the industry as a whole.After gaining considerable recognition for our expertise in the management of technical and regulatory issues we decided there was also a need to address the wider social and political challenges of today. We realized after careful consideration of the challenges facing both industry and the federation that we needed to change our approach and had outgrown the GCPF name that served us well for many ‘our new name reflects the broadening of our sector from its focus on chemical crop protection to the wider plant science industry including Christian Verschueren Director General at CropLife International outlines the change in industry attitudes and availability and variety are greater than at any time in its history. At the same time consumer scepticism has never been higher.One of the most significant challenges we have faced in the past year and will continue to face in the future is the negative public perception of our industry and its products. Many aspects of agriculture derived by scientific innovation continue to be misunderstood. Food production and the development of consumer’s attitudes are complex and interrelated. With almost half of the global population living in urban environments the relationship between people and plants that are grown for food and fibre has become more remote. Value systems continue to change and food manufacturers large retailers and farmers must deliver the products that consumers want. It is in this complex world that our industry must continue to bring the benefits of sustainable agriculture to farmers and consumers while at the same time operating profitably.There is a need to acknowledge and address consumers’ concerns about the role that technological and scientific innovation play in food production and to think carefully about the relationship between society’s values and those of industry. The companies we represent are conscious of the impact their activities have on all stakeholders. We have therefore reshaped our organization so that it is more responsive to those needs and communicates the industry’s messages in a clear and reliable way. Tackling these issues will support sustainable agriculture and improve industry’s long-term business prospects. We are confident that the combined impact of the new federation structure and response to societal concerns will help open the doors to improved dialogue with all stakeholders.We are working hard to improve recognition of the role played by technological progress in making agriculture more environmentally sound socially responsible and economically viable. In order to truly represent all plant science technology and to address issues in an efficient and cooperative manner CropLife International is including biotechnology alongside chemicals in its international representation and issue management activities. We are opening a dialogue with allied biotechnology and seed associations. The evolution will help us move forward as a redefined industrial sector. Since its establishment in December 2000 the federation’s Biotechnology Committee has been working to form strategic alliances with Bio the American Biotech Industry Organization and EuropaBio the European Biotechnology Association.The Committee is also working to coordinate representation in relevant international fora to help establish a more stable coherent transparent and predictable biotechnology’ years. We chose CropLife International as the name to reflect the broadening of our sector from its focus on chemical crop protection to the wider plant science industry including biotechnology. The new federation has expanded the scope of its work to address the issue of sustainable agriculture by concentrating on five strategic priorities global agrochemicals regulatory issues global ag-biotech regulatory issues stewardship and sustainable agriculture society issues and focus on communication.These activities will help propel CropLife International into a new era focused on improving public understanding of the plant science industry improving industry’s understanding of the public’s concerns and improving the global federation’s internal network to make it an effective and resourceful hub of knowledge and expertise. The developed world faces a situation where food quality DOI 10.1039/b 106295f This journal is © The Royal Society of Chemistry 2001 Pesticide Outlook – August 2001 141 INDUSTRY ASSOCIATION regulatory environment that encourages scientific innovation. The federation will also continue to build on its positive reputation and increase efficiency of its existing activities related to agro-chemicals issues.Working with groups such as the OECD Working Group on Pesticides the FAO and the Codex Committee on Pesticide Residues the CropLife International Chemicals Committee is formulating requirements and coordinating policies and programmes for international conventions and regulatory harmonization initiatives including Prior Informed Consent (PIC) Persistent Organic Pollutants (POPs) and the testing of agrochemicals. These efforts should eventually help secure international regulatory regimes that will allow industry to develop and market its products while also meeting the highest environmental safety standards.CropLife International’s new Stewardship and Sustainable Agriculture Committee is coordinating activities for programmes that improve the safe and sound use of crop protection products and contribute to the development of global sustainable agriculture. These initiatives ranging from safe use projects and farmer-training tools to consumer education programmes and public debates demonstrate the new federation’s commitment to serving both farmers and society. Perhaps the most challenging priority facing the global federation and the one that reflects the most significant change in its approach is CropLife International’s aim to understand better society’s concerns relating to the plant science industry. Governments NGOs consumers and other societal groups are demanding that the plant science ‘it is our aim to understand better society’s concerns relating to the plant science industry’ industry become more receptive and responsive to concerns surrounding traditional synthetic crop protection chemicals and new agricultural technologies such as biotechnology.The new federation wants to improve its understanding of these concerns through greater openness and increased dialogue with a variety of stakeholder groups. The new CropLife International Globalization and Society Issues 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 ISBN 0 85404 489 2 £425.00 (package Parts 1 and 2) Crop Protection Agents from Nature 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 Chemistry & Mode of Action of Crop Protection Agents by L. G. Copping & H. G. Hewitt (ISBN 0 85404 559 7 £18.50) 142 Pesticide Outlook – August 2001 Committee will ensure that industry becomes actively involved in the complex social and political debates surrounding issues such as globalization biodiversity food safety risk perception the use of technology in agriculture ethics and corporate social responsibility. As CropLife International becomes a hub of knowledge and expertise for the plant science industry and moves beyond technical and regulatory expertise to tackle broader societal issues it has become necessary for the new federation to become more communications-oriented in all its activities.With a nucleus of communicators working side-by-side with policy mangers the federation will ensure that its views on relevant scientific regulatory and political issues are effectively communicated in the international arena. At the same time the new communications experts are working to collect and deliver reliable information about the plant science industry and its activities to as large and diversified an audience as possible. A significant challenge facing the new federation is the pervasive public perception that the plant science industry is monolithic distant and lacks transparency.CropLife International is working to improve recognition of the role played by technological progress in making agriculture more environmentally sound socially responsible and economically viable. As a federation our role is to develop global polices often in collaboration with allied associations and be a global ambassador for the industry in numerous international fora (i.e. FAO WTO OECD the World Bank Codex Alimentarius and CSD etc). As CropLife International becomes a more effective ambassador we will also be working to develop a more effective internal network providing knowledge management systems that are of considerable value to the industry worldwide. By working closely together at the global regional national and corporate levels we will all become more effective and resourceful supporters of the technology in which we believe. Crop Life International (formerly Global Crop Protection Federation) represents a network of 6 regional and 75 national associations worldwide all working to promote understanding of the plant science industry’s contribution to society. CropLife International covers about 90% of the industry – led by companies such as Aventis Crop Sciences BASF Bayer Dow AgroSciences DuPont FMC Monsanto Sumitomo and Syngenta. For further information contact CropLife International Avenue Louise 143 1050 Brussels Belgium; tel +32 2 542 04 10; fax +32 2 542 04 19; e-mail info@croplife.org or consult our web site www.croplife.org.

ISSN:0956-1250    

DOI:10.1039/b106295f

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

UNDERSTANDING THE STROBILURIN FUNGICIDES Dave W. Bartlett John M. Clough Chris R. A. Godfrey Jeremy R. Godwin Alison A. Hall Steve P. Heaney and Steve J. Maund from Syngenta at Jealott’s Hill International Research Centre1 discuss the biology ecology and Introduction The strobilurins are an important class of agricultural fungicides with a novel mode of action. The earliest examples were first sold in 1996 and there are now four commercial strobilurin fungicides with others in development (Table 1 and Figure 1). This paper describes the science which underpins these fungicides and focuses in particular on their biological and ecological properties and on picoxystrobin a strobilurin currently being developed by Syngenta. The discovery of the strobilurin fungicides was inspired by a group of natural b-methoxyacrylates the simplest of which are strobilurin A and oudemansin A (Figure 2).The natural products were found to be unsuitable as agricultural fungicides but a knowledge of their structures and properties provided a useful starting point for independent programmes of research within ICI (now part of Syngenta) and BASF. When ICI and BASF published their first patent applications other companies also recognised the importance of this class of chemistry and began their own research in the area. ICI and BASF announced the first development strobilurins azoxystrobin and kresoximmethyl respectively in 1992. These products were sold for the first time in 1996 for the control of diseases in temperate cereals.Since that time other products have been announced namely trifloxystrobin from Novartis (this product was recently sold to Bayer) metominostrobin from Shionogi pyraclostrobin from BASF and picoxystrobin from Syngenta. Azoxystrobin and picoxystrobin retain the methyl b-methoxyacrylate group of the natural fungicides while the others contain modified toxophores. More recently DuPont and Aventis respectively have discovered famoxadone and fenamidone fungicides which are not Table 1. The strobilurin fungicides. Company Announced Strobilurin 1996 1996 1999 1999 In development In development 1992 1992 1993 1998 2000 2000 resistance management of the strobilurins especially picoxystrobin the latest member of the class First Sales Figure 1.The strobilurin fungicides. structurally-related to the strobilurins but which have the same mode of action. Sales of the strobilurin fungicides were approximately $600 million in 1999 representing just over 10% of the global fungicide market. The huge impact of the strobilurins on agriculture is well exemplified by the development of azoxystrobin which has now been registered for use on a broad spectrum of fungal diseases on 84 different crops in 71 countries representing over 400 crop/disease systems. Leading crops include cereals vines fruit and vegetables and peanuts. Sales of azoxystrobin reached $415 million in 1999. Of this value the UK market alone accounted for 8% of sales primarily from sales on wheat and barley crops.The strobilurins act by inhibiting mitochondrial respiration in fungi. They bind at the Qo-centre on cytochrome b and block electron transfer between cytochrome b and cytochrome c1. This disrupts the energy cycle within the fungus by halting the production of ATP. Figure 2. The simplest of the natural strobilurins. Syngenta Azoxystrobin1 Syngenta Kresoxim-methyl BASF Metominostrobin Shionogi Trifloxystrobin2 Bayer Pyraclostrobin BASF Picoxystrobin 1 Discovered by ICI now part of Syngenta. 2 Discovered by Novartis sold to Bayer in 2000. 1 Syngenta Jealott’s Hill International Research Centre Bracknell Berkshire RG42 6EY UK. DOI 10.1039/b106300f This journal is © The Royal Society of Chemistry 2001 Pesticide Outlook – August 2001 143 DISEASE CONTROL DISEASE CONTROL As a family the strobilurin fungicides give high levels of activity against a wide range of crop diseases.Indeed one activity on cereals that is superior to current commercial of the key reasons for the outstanding commercial success of strobilurin fungicides. It has also demonstrated curative azoxystrobin is that it gives control of fungi from all four activity against a range of cereal diseases under field classes of plant pathogens namely the Ascomycetes Basid- conditions which is attributable to its good uptake into the iomycetes Deuteromycetes and Oomycetes. Therefore leaf. Figure 4 shows that picoxystrobin gives better curative azoxystrobin gives control of combinations of pathogens activity than the commercial strobilurins azoxystrobin and which was previously only possible through the mixture of trifloxystrobin.two or more fungicides e.g. downy and powdery mildew of grapevines. However not all strobilurins are broad spectrum fungicides used on a wide range of crops. For example metominostrobin from Shionogi has been developed for use exclusively on rice. Similarly other strobilurins do not offer high level control of all four classes of fungal plant pathogens; kresoxim-methyl and trifloxystrobin are both relatively weak against rust diseases and downy mildews. Of the recently announced strobilurins pyraclostrobin from BASF is a broad-spectrum strobilurin for use on a wide range of crops whereas Syngenta’s picoxystrobin is a specialist cereal fungicide.Picoxystrobin biology Broad spectrum cereal foliar fungicides designed for the current market must control a wide range of cereal diseases because there are more than 15 fungal pathogens which can have a major impact on grain yield and quality. In addition they should possess curative activity i.e. the ability to control diseases after infection has already become established. Curative activity is particularly important for cereal fungicides applied early season because at this timing disease is likely to be established within the overwintered crop. Redistribution properties are also important features for broad spectrum cereal foliar fungicides; uptake into the leaf and systemic movement are necessary for the control of deep-seated diseases such as Septoria and rusts while vapour activity is important for powdery mildew control in order that the active ingredient can fully penetrate the tightly woven “mycelial mat” on the leaf surface.Perhaps the most important feature for cereal fungicides in the current climate of economic difficulties for farmers and increasing environmental awareness is that they must deliver sufficient grain yield and quality benefits to justify their use. Finally any agrochemical needs to have a good safety and environmental profile for reasons of product stewardship and registration. All of these requirements drove the extensive programme of research which led to the selection of picoxystrobin as a broad spectrum cereal strobilurin fungicide.Broad spectrum activity Picoxystrobin demonstrates an outstanding breadth of spectrum in cereals being highly active against both Septoria diseases of wheat Helminthosporium species on wheat barley and oats Rhynchosporium on barley and rye Ramularia on barley and Puccinia rust diseases and strobilurin-sensitive powdery mildews on wheat barley oats and rye. Its broad spectrum of activity means that the green leaf area of the crop is maintained during the important grain filling period. Figure 3 summarises the breadth and level of activity of picoxystrobin against the key cereal diseases compared to current commercial strobilurins. 144 Pesticide Outlook – August 2001 Picoxystrobin delivers a breadth of spectrum and level of Redistribution properties The redistribution properties of picoxystrobin play an important role in delivering its broad spectrum activity against cereal diseases.Typically around 40% is taken up into leaves by one day after application approximately half of which enters the leaf within two hours of spraying. Material remaining on the leaf surface has excellent biological rainfastness e.g. there was no decline in control of Septoria tritici on wheat when comparing between plants sprayed with picoxystrobin (250 g ai/ha) under rain-free conditions and plants exposed to 10mm of simulated rainfall for one hour applied two hours after spraying. Once absorbed into the leaf picoxystrobin is mobile in the xylem (systemic) moving with the water flow in the transpiration stream.Picoxystrobin also moves in the vapour phase at the leaf surface and has been shown to be translocated in the xylem following its absorption into the leaf from the vapour phase. The redistribution properties of picoxystrobin are unique amongst commercial strobilurin fungicides and those in development because it is the only one showing both vapour activity and xylem systemicity. The consequences of these unique properties for disease control have been demonstrated by applying various fungicide treatments to a defined zone on wheat leaves inoculating the complete leaves with spores of wheat powdery mildew and monitoring disease development. Picoxystrobin demonstrated both vapour activity in the zone toward the leaf base and xylem mobility to give complete disease control to the leaf tip (Figure 5) whereas azoxystrobin showed systemic activity only and trifloxystrobin and kresoxim-methyl showed vapour activity only.Table 2 summarises the redistribution properties of strobilurins. Grain yield and quality Treatment of cereals with picoxystrobin has consistently given excellent yield benefits together with improvements in quality through an increased frequency of larger-sized grain. These yield and quality benefits are attributable to its broad spectrum disease control good maintenance of green leaf area and crop safety. In field trials against a range of foliar diseases of winter wheat picoxystrobin-based programmes delivered an average of 0.2 t/ha more than the corresponding trifloxystrobin-based programmes.Indeed in 21 European wheat field trials over three years treatment with picoxystrobin gave a 22% increase in yield over the untreated identical to that achieved with a strobilurin (kresoxim-methyl) in mixture with a triazole (epoxiconazole). The analysis of data from 21 European field trials over 3 years on winter barley showed that picoxystrobin gave a mean yield increase of 0.4 t/ha over kresoxim-methyl/epoxiconazole. Moreover the Figure 3. Activity of picoxystrobin against the key cereal foliar diseases compared to current commercial strobilurins at their recommended use Table 2. Redistribution properties of strobilurins.1 Movement into leaf Vapour active Metabolic stability in leaf Translaminar movement Xylem systemic Systemic movement to new growth in cereals Phloem mobile 1 Source Syngenta; *n.d.= no data rates. Figure 4. Curative activity of strobilurins against cereal diseases (as shown in glasshouse tests). v.low yes low low no low no yes yes yes no no yes no Figure 5. Picoxystrobin demonstrates both vapour and systemic activity in cereal leaves. DISEASE CONTROL Picoxystrobin Metominostrobin Pyraclostrobin Kresoxim-methyl Trifloxystrobin Azoxystrobin medium yes yes yes yes v. low no yes low no high no n.d.* yes yes low yes low low no no no yes no no no yes no picoxystrobin treatment gave the superior yield in 17 of the 21 trials demonstrating the consistency of yield benefit that picoxystrobin delivers.Similar yield benefits of picoxystrobin over kresoxim-methyl/epoxiconazole were shown in 21 European field trials on winter barley over three years (Figure 6). These improvements in cereal yields with picoxystrobin have been accompanied by improvements in grain quality through increases in the frequency of larger-sized grain. Results from winter wheat field trials in which grain greater than 2.2 mm in diameter was weighed separately from grain less than 2.2 mm in diameter clearly showed that the increase in overall yield with picoxystrobin was due to an increase in yield of the larger sized grain fraction. Ecological profile The commercialised strobilurins azoxystrobin trifloxystrobin and kresoxim-methyl are considered safe to birds and mammalian wildlife bees earthworms and beneficial insects (The e- Pesticide Manual 2000).In standard laboratory studies required for pesticide registration all of the above strobilurins are relatively toxic to aquatic organisms (Table 3). The more recently announced compounds picoxystrobin and pyraclostrobin also show high inherent toxicity to aquatic organisms. There is an indication that as the lipophilicity (octanol water partition coefficient) rises effects on aquatic organisms also intensify. Linked increases in toxicity with lipophilicity are a common phenomenon for pesticides and other organic chemicals.However although such data from standard toxicity tests can be useful for expressing the inherent ‘hazard’ of chemicals they do not necessarily reflect the potential for adverse effects during normal agricultural use in other words the true ‘ecological risks’ of the compound. To evaluate potential risks in use it is necessary to consider both how non-target organisms will be exposed to the compound and Pesticide Outlook – August 2001 145 50 Algae EC (mg L–1) DISEASE CONTROL Table 3. Toxicity of strobilurins to aquatic organisms. Compound Fish 96 h LC (mg L–1) Daphnia 48 h EC50 (mg L–1) 120 63 259 186 16 Azoxystrobin Kresoxim-methyl Trifloxystrobin Pyraclostrobin Picoxystrobin 56 18 Figure 6.Winter barley yield responses in 21 individual trials. 470 190 15 6 65 the ecological characteristics of the organisms involved (i.e. where and how they live and reproduce). The development of such a risk assessment is a scientifically demanding process that requires the production of a vast range of data. This includes studies to understand the fate of the chemical in the various environmental matrices (air soil water sediment) as well as its effects on non-target organisms. Exposure of organisms in the environment also has to be estimated through the use of a variety of exposure models. For certain compounds it may also be necessary to understand the range of sensitivity of the non-target organisms potentially affected and how their ecological dynamics may influence responses to chemical exposure.Substantial scientific investment in such comprehensive risk assessment packages means that a tremendous amount is known about the new strobilurin pesticides. For example for picoxystrobin risk assessments have been carried out on all relevant groups of non-target organisms (Godwin et al. 2000) and show that the compound presents low risks under normal use. To demonstrate some of the complexity that can be involved in generating such risk assessments let us consider the potential risk of picoxystrobin to aquatic invertebrates. Picoxystrobin is applied at 250 g active ingredient per hectare. The EU model for predicting concentrations in surface water makes some worst-case assumptions e.g.that there is always a 30 cm deep static water body located 1 m downwind from the point of application. Resulting estimates of the initial concentration of picoxystrobin at the water’s edge arising from spray drift would be approximately 2 mg L–1. Whilst this is nearly an order of magnitude less than the toxicity value on Daphnia a 100-fold safety 146 Pesticide Outlook – August 2001 50 Octanol water log P 2.5 3.4 3.4 4.0 3.6 factor is normally applied to account for potential differences in sensitivity between species. Since this triggers further investigation tests were conducted on a wide range of aquatic invertebrate species to explore interspecies sensitivity (Table 4). These demonstrated that Daphnia were in fact among the most sensitive species.None of the species tested was 100 times more sensitive and worst-case exposure concentrations were still below the toxicity to the most sensitive species a copepod zooplankter Diaptomus. Consequently adverse effects on invertebrates from worst-case exposure concentrations seemed unlikely. This conclusion was further explored in an aquatic microcosm study. These are highly detailed studies that evaluate the effects of the pesticide on complex aquatic communities in replicated outdoor experimental systems (Figure 7). Simulated spray drift events did not result in adverse effects on the aquatic invertebrate community even after three applications at Pesticide Manual 2000 Pesticide Manual 2000 Pesticide Manual 2000 Ammermann et al.2000 Godwin et al. 2000 Table 4. Toxicity of picoxystrobin to a range of aquatic invertebrate species. Species Diaptomus Daphnia magna Daphnia pulex Crangonyx Macrocyclops Asellus Agrypnia Cloeon Tubifex Chironomus Chaoborus Dugesia Polycelis Erpobdella Limnea Coenagrion Notonecta Naucoridae Brachionus Common name Copepod Water flea Water flea Shrimp Copepod Slater Caddisfly Mayfly Worm Non-biting midge Phantom midge Flat worm Flat worm Leech Snail Damselfly Water boatman Water bug Rotifer 50 48 h EC (mg L–1) 5 18 > 51 63 87 152 158 194 299 326 332 c.450 c. 450 c. 450 > 1000 > 1000 > 1000 > 1000 > 4000 Reference Figure 7. Pond microcosms at Jealott’s Hill International Research Centre. Samples for water quality and plankton are being collected. rates that were ten times greater than those predicted from the worst-case EU exposure model. This clearly demonstrated that picoxystrobin is of low risk to the aquatic ecosystem and requires no aquatic buffer zones. Sensitivity of fungal populations to the strobilurins and resistance management The strobilurin fungicides together with famoxadone and fenamidone bind at the Qo site of the cytochrome bc1 complex. Together these compounds form a new crossresistance group designated QoI by the Fungicide Resistance Action Committee (FRAC).Despite intensive monitoring over the past two or three years no significant shifts in sensitivity to the QoI group of fungicides have been detected in the majority of cereal pathogens including Septoria tritici Pyrenophora teres Rhynchosporium secalis and Puccinia spp. By contrast strobilurin resistance has progressed rapidly in wheat powdery mildew (Blumeria graminis f.sp. tritici) resistant populations were first detected in May 1998 and by 2000 high frequencies of resistant spores (2-99%) were reported across Northern Germany Northern France and the UK. In addition in 2000 resistance was detected in barley powdery mildew (B. graminis f.sp. hordei) at localised sites in Northern France Northern Germany and Scotland (Heaney et al.2000). QoI resistance in both wheat and barley powdery mildew correlates with a specific point mutation leading to the substitution of glycine by alanine at position 143 (according to the Saccharomyces cerevisiae numbering system) of cytochrome b (Sierotzki et al. 2000). This G143A point mutation has also been identified in QoI-resistant isolates of Sphaerotheca fuliginea Plasmopara viticola Pseudoperonospora cubensis and Mycosphaerella fijiensis. The resistant field isolates of B. graminis show large resistance factors of >1000 compared to the baseline DISEASE CONTROL isolates. They are thought to have spread rapidly due to the relative fitness of the G143A mutation in B. graminis along with the epidemiology of the pathogen.Previous experience with ethirimol the benzimidazoles and the demethylation inhibitors (DMIs) such as the triazoles has demonstrated the high risk for resistance associated with B. graminis. In each of these cases resistance has evolved within 3–6 years of the introduction of the chemical. The key question now is whether the other cereal pathogens will follow the powdery mildew model in the evolution of resistance. Indeed M. fijiensis is closely related to S. tritici (Mycosphaerella graminicola) suggesting that there is a risk of target site resistance in the latter pathogen. Nevertheless prior experience in particular with the DMIs has shown that resistance in many key cereal pathogens including S. tritici has taken considerably longer to develop (12 years or greater) compared to powdery mildew which provides an opportunity for the implementation of anti-resistance strategies.In response to the emergence of resistance in B. graminis FRAC now recommends that a strobilurin is mixed with an effective partner for the control of powdery mildew. It is also advised that the number of QoI applications is limited to two out of three sprays per season and that effective doses of a QoI fungicide are used in order to decrease the risk of resistance developing in other cereal pathogens. In addition mixtures of fungicides in different cross-resistance groups are preferred for the control of all cereal diseases. Conclusions The strobilurins are an outstanding new class of fungicides.Registrations have been obtained on a wide range of crops throughout the world to the point where the strobilurins can now be considered to be one of the most valuable classes of single-site fungicides ever discovered by the agrochemical industry. They have set new standards in disease control and more importantly for the grower in the delivery of improved yields and quality. Indeed the success of the strobilurins in the fungicide market simply reflects the benefits that they bring to those producing the crop. New strobilurins such as picoxystrobin continue their development and the dependence of crop protection on the strobilurins is likely to increase still further. Further reading Ammermann E.; Lorenz G.; Schelberger K.; Mueller B.; Kirstgen R.; Sauter H.(2000) BAS 500 F – the new broad-spectrum strobilurin fungicide. Proceedings of the BCPC Conference – Pest and Diseases 2000 2 541–548. Clough J. M.; Godfrey C. R. A.; Godwin J. R.; Joseph R. S. I.; Spinks C. (1996) Azoxystrobin a novel broad-spectrum systemic fungicide Pesticide Outlook 7 16–20. Clough J. M.; Godfrey C. R. A. (1998) “The Strobilurin Fungicides” in “Fungicidal Activity Chemical and Biological Approaches to Plant Protection” Eds. Hutson D.H. and Pesticide Outlook – August 2001 147 DISEASE CONTROL Miyamoto J. Wiley Series in Agrochemicals and Plant Protection pp. 109–148. Godwin J. R.; Bartlett D. W.; Clough J. M.; Godfrey C. R. A.; Harrison E. G.; Maund S. J. (2000) Picoxystrobin A new strobilurin fungicide for use on cereals.Proceedings of the BCPC Conference – Pests and Diseases 2000 2 533–540. Godwin J. R. et al. The strobilurin fungicides Pest Management Science in preparation. Heaney S. P.; Hall A. A; Davies S. A.; Olaya G. (2000). Resistance to fungicides in the QoI-STAR cross-resistance group current perspectives. Proceedings of the BCPC Conference – Pests and Diseases 2000 2 755–762. Sierotzki H.; Wullschleger J.; Gisi U. 2000. Pesticide Biochemistry and Physiology 68 107–112. WORLD’S WORST WEEDS The title of this forthcoming symposium to be held at Brighton on 12 November 2001 in conjunction with this year’s BCPC Conference Weeds 2001 comes from the title of the first of three books by Leroy Holm et al.1–3 Since weeds account for significant costs in all agricultural systems this symposium to be chaired by Charlie Riches (NRI University of Greenwich UK) will review the current distribution and status of some of the most important and intransigent weed groups in world agriculture together with the development of rational practices for their control.Holm places Cyperus rotundus (purple nutsedge) as the world’s worst weed and so it is fitting that John Terry (IACR Long Ashton UK) will start off the symposium with a presentation entitled The Cyperaceae – still the world’s worst weeds? Using examples from temperate and tropical areas emphasis will be placed on how change in agricultural practice effects weed floras and how recent developments in weed biology and ecology can lead to sustainable environmentally acceptable management systems for key species.Aquatic weeds like water hyacinth (Eichhornia crassipes) and parasitic weeds like Striga and Orobanche would also 148 Pesticide Outlook – August 2001 The e-Pesticide Manual (2000). The British Crop Protection Council. (Ed. C. D. S. Tomlin). All the authors work for Syngenta at Jealott’s Hill International Research Centre Bracknell UK and have been involved with different aspects of the discovery evaluation and development of picoxystrobin. John Clough and Chris Godfrey are synthetic chemists; Jeremy Godwin is a plant pathologist; Dave Bartlett is a plant physiologist; Steve Maund is an environmental scientist; and Alison Hall and Steve Heaney have studied the resistance management of the strobilurins. be high on anyone’s worst weed list and so they will feature in presentations by Raghavan Charudattan (University of Florida USA) and Malcolm Press (University of Sheffield UK) respectively. Chris Parker (consultant Bristol UK) will outline how we might be able to predict the emergence and prevent the spread of new weed problems and rounding off James Bunce (Beltsville Agricultural Research Centre Maryland USA) will discuss how weed populations might be affected by future global climate change. For further information please contact the BCPC Conference Secretariat 5 Maidstone Buildings Mews Bankside London. SE1 1GN UK (Tel +44 (0)20 7940 5555; Fax +44 (0) 20 7940 5577; Email conference@bcpc.org). 1. Holm L.; et al. (1977). The World’s Worst Weeds. University of Hawaii Press (Honolulu). 609 pp. 2. Holm L.; et al. (1979). A Geographical Atlas of World Weeds. John Wiley (New York). 391 pp. 3. Holm L.; et al. (1997). World Weeds Natural Histories and Distribution. John Wiley New York. 1129 pp.

ISSN:0956-1250    

DOI:10.1039/b106300f

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

CROP PROTECTION IN TURKMENISTAN Graham Matthews from the International Pesticide Application Research Centre (IPARC) at Silwood Park in the UK reports on a recent trip to Turkmenistan as part of a TACIS EU funded project Introduction Turkmenistan is a former Soviet republic in west-central Asia bordering Kazakhstan Uzbekistan Afghanistan and Iran. It is located in a broad dry lowland extending east from the Caspian Sea; nearly 80% of the country is taken up by the Kara-Kum (Black Sand) desert. Agriculture Agriculture accounts for almost half the value of Turkmenistan’s economic production. Cotton the chief crop occupies more than 50% of the farmland. Other farm products include grains grapes potatoes wool and Persian lamb (a fur taken from young lambs).Some Turkmen raise camels Karakul sheep and a special breed of Turkoman horses. Pelts from the Karakul sheep are highly prized for fur coats. Some farmers also raise silkworms. Farms depend on melting snows of the Pamir mountains feeding the Amu Darya and Syr Darya rivers. Part of the flow along the Amu Darya has been diverted to the Karakum canal that stretches 750 miles across southern Turkmenistan towards the Caspian Sea. Although the building of the canal has been severely criticised due to the consequent ecological disaster of the shrinking of the Aral Sea its development was planned to vitalise farming and living conditions in Turkmenistan. Crops in Turkmenistan can only be grown by irrigation and hence most of the farming regions in Turkmenistan lie along the Amu Darya river and the Karakum Canal.Currently the Murgah river is virtually dry due to the drought in Afghanistan so farms in the Mary velayat depend on the canal water. Insect control Insecticides are not widely used today in Turkmenistan. The extremely cold winters undoubtedly reduce the severity of most potential insect pests in the large areas of wheat cotton and lucerne grown in the desert under irrigation. Despite the cold winter important beneficial insects thrive there in the absence of large-scale insecticide use. Biological control is being used in many areas. For example golden eye (Chrysopa) is a common lacewing keeping aphid and thrips populations in check. Coccinellids also play a key role in biological control.If the cotton bollworm Helicoverpa armigera population increases farmers can get Trichogramma and/or Bracon parasitoids from bio-laboratories for release in cotton (see Pesticide Outlook 1993 4(45) 36); however the equipment at these bio-laboratories has declined over recent years. DOI 10.1039/b106291n This journal is © The Royal Society of Chemistry 2001 Pesticide Outlook – August 2001 149 Acknowledgements The author acknowledges financial support from NIAB which made his trip to Turkmenistan possible. NIAB is currently managing this project to increase the output and improve the quality of cotton produced in Turkmenistan. The project is financed by the European Union’s Tacis programme which provides grant finance for know-how to foster the development of market economies and democratic societies in the New Independent States and in Mongolia.TURKMENISTAN Disease control The main market for pesticides is fungicidal seed treatments as cotton seedlings are prone to disease especially when growth is slowed by low night-time temperatures. Bronocol is the main ingredient used. Weed control Frequent passage of tractors with harrows for mechanical weeding leads to soil compaction affecting crop development so there is a potential for increased herbicide use. So far the small quantity of herbicides imported is applied on wheat but many fields have large infestations of grass weeds (e.g. Cynodon Echinocloa) as well as Amaranthis and Convolvulus. Application There is virtually no information available locally on spraying techniques use of different nozzles or sprayer calibration.In many areas only old Russian sprayers are available but if a sprayer is required the large farms on the etraps (administrative regions) can use one from the local mechanisation centre. Some have relatively new highclearance self-propelled John Deere sprayers while others have trailer units. Spray volumes applying herbicides are typically about 300 l ha–1. While at the end of the winter crop season in heated glasshouses much higher volumes of an insecticide spray are used in May and June to try and prevent whiteflies migrating from tomatoes to nearby cotton fields. The use of defoliants has declined with a return to hand picking due to the deterioration and lack of spare parts of Russian mechanised pickers. Outlook With sensible integration of certain pesticides and maintenance of biological control it should be possible to increase yields provided sufficient water is judiciously applied at critical stages of crop development.

ISSN:0956-1250    

DOI:10.1039/b106291n

出版商:RSC    

年代:2001

数据来源: RSC