摘要:

COMPANY NEWS Bayer and Aventis Bayer’s takeover of Aventis CropScience is almost complete. Agreement has now been reached on the key points of the sale. Bayer will pay EUR 5.5 bn – simultaneously taking over debts of EUR 2 bn. Schering AG which has a 24% stake in Aventis CropScience is expected to receive over EUR 1.3 bn. Subject to the approval of the antitrust authorities it is planned to integrate the crop protection activities of both companies into a newly established company that will be a separate legal entity within the Bayer Group. The new company will be one of the top players in the global crop protection market (No. 1 in insecticides; No. 2 in fungicides) with approximately 23,000 employees and combined sales approaching EUR 7 billion.The merger will mean cost savings of EUR 500 M/y. Aventis will remain responsible for any risks arising from the StarLink corn affair in the USA. Half-year results 2001 …Bayer Sales in Bayer’s Agriculture segment in 1H 2001 matched the previous year’s level of EUR 2.1 bn. The operating result slipped 7% to EUR 0.5 bn. The sluggishness of the economy in the US and Latin America had an adverse effect while sales in Europe were hampered by weather-related sales declines in products for cereals and mounting competitive pressure from generic herbicides. …BASF Sales in the first-half of 2001 rose 78% to nearly EUR 2.3 bn. By December 2001 BASF expects to exceed the envisioned EUR 125 M in annual cost saving synergies following the aquisition of the agricultural part of American Home Products.The closure of its Princeton research and development centre will add another considerable portion of cost savings. It has great confidence in its new strobilurin fungicide F500. It expects 14 active ingredients to be launched by 2006; its total R&D commitment is about EUR 400 M per year. BASF is very confident to meet the annual synergy effects of EUR 250 M from 2002 onward. …Syngenta Syngenta half-year results 2001 have been negatively affected by damp and cold 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.170 Pesticide Outlook – October 2001 This journal is © The Royal Society of Chemistry 2001 weather conditions and low prices for agrochemicals. Turnover decreased by 4% to $4.03 bn. The operating result decreased by 9% to $1.06 bn and the operating margins remained at 26.3%. Net profits remained almost unchanged with $400 M ($399 M in 1H 2001). However net profits decreased by 5.5% to $377 M in 1H 2001. Syngenta plans further cost-cutting measures and will close down 10 of its 47 global production facilities by 2004. In addition to this the company will close down half of its 12 technology centres. Overall Syngenta plans to cut 3000 jobs worldwide to a total of 20,000. Agricultural e-commerce United Business Media (UBM) is to close Farmgate.co.uk.The closure is the latest to hit agricultural e-commerce recently. Globalfarmers. com dismissed half its staff two months ago with receivers being appointed in early July but it was bought out by ADAS whose on-line consultancy and information services will now be supplemented by a trading arm. The French site Agrifirst.com dropped plans to open in the UK. The long-term future of e-commerce could be secure however with the cooperation between distributor giants such as Banks Cargill Dalgety Kemira DuPont and Terra to found First4farming due to start on-line trading in 2002. UBM is also closing Farming News a move which may speed growers from newsprint to internet. Isagro Isagro is in talks with Dow Chemical to dissolve the companies’ 50-50 pesticides distribution joint venture Isagro Italia which had sales of EUR 44 M in 2000.The company is to build a unit in Panoli India to manufacture tetraconazole. The site was obtained with the recent purchase of Calcutta-based RPG Life Science. This acquisition plus the recent acquisition of Caffaro’s agchems business have almost tripled Isagro’s sales to over EUR 180 M/y. Isagro will invest EUR 5 M to install new technology and upgrade the former Caffaro copper fungicides plant at Adrioa Italy which has capacity of 20,000 tonnes/y. Isagro is also spending EUR 60 M to develop two new fungicides and one herbicide –- due for launch between 2004 and 2006. Nufarm Nufarm has acquired the production and formulation units of pesticides and speciality chemicals producer Artfern fron Wesfarmers Landmark.Nufarm has also acquired a 50% stake in Artfern’s trading and distribution business. Artfern makes sulfonylurea herbicides and a range of surfactants and additives at Lara Australia. Nufarm is strongly focussed on continued global expansion and a return to strong growth in profits. But the company recently downgraded its profits forecast for fiscal 2001. It expects to return to growth in profits in 2001–2002. Syngenta in Japan Syngenta is buying out the remaining 50% stake in the Japanese crop protection and distribution company Tomono Agrica. Syngenta already owns 50% of the company. Syngenta will concentrate on improving the company’s position in Japan.In Japan Syngenta and Tomono Agrica have combined sales of $250 M accounting for about 10% of the Japanese market for crop protection agents. Bayer-Syngenta dispute The patent dispute between Bayer and Syngenta over neonicotinoid insecticides has been won by Syngenta. The US Patent and Trademark Office has ruled that Syngenta was the first to invest in the thianicotinyl class of neonicotinoid insecticides. The ruling includes Syngenta’s proprietary compound thiamethoxam but does not affect a second patent held by Bayer on neonicotinoid insecticides. Bayer intends to continue with two further lawsuits against Syngenta for infringement of this patent. A counter-suit was filed by Syngenta in Delaware earlier in 2001. Banks Cargill A seed processing plant has been opened by Banks Cargill at Sandy UK. The £3 M high-technology plant can process and apply pesticide dressings to seed at 60 tonnes/hour. The newly merged company is confident that the plant can meet early demand for treated cereal seed this autumn. DOI 10.1039/b108597m

ISSN:0956-1250    

DOI:10.1039/b108597m

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

Dutch to tax pesticides The government in the Netherlands has proposed a tax to reduce the use of pesticides from 2003. The income generated will be used to develop more environmentally friendly alternatives for combating weeds pests and diseases. It is hoped that by 2005 at least 90% of companies handling pesticides will have voluntarily acquired an integrated crop production certificate showing that they are operating on a sustainable basis. If this figure is not achieved then a ban will be imposed on the use of chemical agents by non-certified companies. The agricultural sector is objecting to the proposed tax. IPU maintaining status quo Isoproturon (IPU) looks likely to remain widely used in the UK for the remainder of 2001 despite water company pressure for a ban on its use.There are no expected changes in legislation from the Pesticides Safety Directorate that will affect IPU use in Autumn 2001. IPU still has a strategic role to play in controlling key grass weeds and certain broad-leaved weeds. It is one of a limited number of options for grass weed control in winter barley and one a limited number of active ingredients controlling ryegrass in wheat and barley. But the problem of IPU and several other products that find their way into surface water is a significant problem for water companies. The IPU Stewardship Group recognises the need to protect surface water and has come up with a set of guidelines for the use of IPU. Cefic and ECPA commitment to Rotterdam Convention Since 1 April 2001 Cefic and the European Crop Protection Association (ECPA) have started implementing a unilateral initiative to support the Rotterdam Convention on the Prior Informed Consent (PIC) Procedures for Certain Hazardous Chemicals and Pesticides in International Trade.Under this initiative approved by the Cefic Board in June 2000 Cefic members will notify their first annual export of chemicals and pesticides that are banned or severely restricted under Community legislation concerning the export and import of certain dangerous chemicals (Regulation 2455/92). Existing Community legislation already provides for notification of the first export ever of such chemicals but this will now be done annually under this commitment.The process of completing a final European DOI 10.1039/b108594h REGULATORY NEWS Commission proposal implementing the Rotterdam Convention and getting it adopted by Council and Parliament will take at least two years (http://www.cefic.org) Endocrine disruptors new EC approach The European Commission has decided to modify its strategy on endocrine-disrupting chemicals by depending mainly on two existing chemical programmes to evaluate the endocrine-disrupting properties of chemicals that are already being tested for other reasons. Initially the strategy required evaluation of 66 potential endocrine disruptors on the Commission’s priority list presented in Summer 2000. 46 substances are being considered for assessment including 15 chemicals prioritised under the 1993 Existing Substances Regulation and 31 pesticides being evaluated under the 1991 Plant Directive.The Commission also intends to collect data on 435 candidate substances that still have inadequate endocrine disruptive data. Several previously identified substances have been eliminated. Thiophanate-methyl risk assessment raises concerns The US Environmental Protection Agency’s Office of Pesticide Programs (OPP) recently conducted further risk assessment research into thiophanate-methyl and its major metabolite carbendazim. Studies have shown both thiophanate-methyl and carbendazim to be carcinogenic and teratogenic in animals. The OPP’s research concluded that current levels of exposure to thiophanate-methyl through diet and drinking water may pose health risks for babies children and females aged 13–50 years.The chronic aggregate risk was also of concern in children and females aged 13–50 years. The cancer aggregate risk from thiophanate methyl to the general public exceeded acceptable levels as did the risk from carbendazim. Both thiophanatemethyl and carbendazim also threaten the health of small animals fish and invertebrates. The manufacturer Cerexagri (formerly Elf Atochem North America) has issued a detailed response criticising the OPP’s preliminary risk assessment. Possible industry alliance on triazoles BASF Bayer Dow and Syngenta are considering forming an alliance to provide the data needed to apply for registration of Pesticide Outlook – October 2001 171 This journal is © The Royal Society of Chemistry 2001 triazole fungicides with the US Environmental Protection Agency.The alliance may be affiliated to the European Triazole Assessment Group. At present triazole fungicides are used in the US under special emergency exemptions. New European Directive A directive amending Directive (91/414/EEC) regarding the placing of plant protection products on the market (2001/36/EC) has been released in the Official Journal. Amended were the requirements of the original Directive for submitting a dossier for authorisation when an active substance consists of or contains microorganisms. The new Directive presents a substantial transformation in the supply of information regarding human exposure and environmental risks from microorganisms.National Regulations must be enforced by 1 May 2002. Snippets …herbicide use in Belgium is to be lessened by rewarding farmers who use mechanical means to control weeds. Over the next 5 years those who use mechanical means only will receive an annual bonus of £85/ha. Those who introduce strip spraying in row crops instead of conventional overall spraying will receive £28/ha. …the EU is not expected to change its Common Agricultural Policy (CAP) fundamentally in 2002 although subsidies in future will be for good environmental practice. The UK and German governments have asked the EU to review CAP in the light of rural support environmental sustainability and the expectations of consumers. The European Crop Protection Association (ECPA) is supporting this approach. …following US reports that there were adverse effects on human health and the environment from the use of the insecticide aldicarb a review was conducted by the Australian National Registration Authority for Agricultural and Veterinary Chemicals (NRA). Because application in Australia is by the use of granules below the surface of the soil the NRA has declared aldicarb safe to use on cotton citrus fruits and sugar. There will a closer monitoring programme over the next three years on the use of aldicarb in citrus orchards.

ISSN:0956-1250    

DOI:10.1039/b108594h

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

R&D NEWS Weed control …cleavers control FMC has approval for sale of its new preemergence herbicide Centium 360 CS for the control of cleavers (Galium aparine) in winter oilseed rape and winter beans. Its active ingredient clomazone has a unique mode of action affected weeds being bleached at the growing point prior to dying. Further approval is being sought for use on spring peas spring beans potatoes and lupins. The product formulated as a capsule suspension is recommended to be used in mixture with a compound such as metazachlor. If Dow AgroSciences is successful in developing two new products controlling cleavers in cereals could become much easier. Development herbicides GF184 and GF185 combine fluroxypyr with florasulam.Dow hopes products will be available in the first quarter of 2002. In addition to offering wider cleavers treatment windows they control a broader range of weeds than either fluroxypyr or florasulam alone. Approval for use on winter and spring varieties of wheat barley oats rye and triticale is being sought …blackgrass (and brome) control BASF finally has approval in the UK for its grass weed killer Crystal previously known as ACH210 and sales are due for Autumn 2001 use. The product contains the new active ingredient flufenacet plus 300g/litre of pendimethalin. Growers will see a substantial improvement in control of blackgrass over that achieved with the current standard product Avadex (triallate). BASF also claims activity against brome grass as do Monsanto for Monitor (sulfosulfuron) and Bayer for Attribut (propoxycarbazone-sodium).…cheatgrass control Bromus tectorum (cheatgrass) is a fast spreading invasive weed that dominates more than 100 million acres (40 million hectares) in the Western US. It is a major fuel for wildfires in non-forested areas competes aggressively for water and nutrients and destroys the natural habitats for wild animals. The US Bureau of Land Management the Idaho State Department of Agriculture and the US Forestry Service have identified imazapic (Plateau) as a very effective herbicide for its control. The compound has been shown to control cheatgrass without damaging the desirable grasses or legumes favoured by wildlife.When applied in the Autumn complete cheatgrass control has been achieved. 172 Pesticide Outlook – October 2001 This journal is © The Royal Society of Chemistry 2001 Slug control …basic research into slug control is taking place at the Central Science Laboratory (CSL). York and the University of Aberdeen. CSL is investigating the use of hormones involved in reproductive maturation; two identified are the dorsal body hormone and the optic tentacle hormone. The delivery of the hormones by the protein fusion technique as used successfully in insect control is to be investigated. Aberdeen is working on the application of active ingredients at present applied to the soil as granules direct to the seed. Metaldehyde and methiocarb are the two most promising compounds.…DeSangosse which supplies metaldehyde pellets against slugs has launched an interactive web-site on which growers can develop their own answers to controlling the pests. Advice and access to independent experts can be found on http:// www.nomoreslugs.com. …Bayer has been conducting field trials to confirm the molluscicide effect of its insecticide seed dressings Sibutol Secur Raxil Secur and Baytan Secur all containing imidacloprid. Since their introduction in 1998 growers have noted that their winter cereals were less palatable to Insect control …aphid control Ishihara Sangyo has developed a new broad-spectrum insecticide code-named IKI-220 which is active against aphids thrips and other pests.It will file for registration for the pesticide in 2002. IKI-220 will be sold under the tradename Urara. …garlic-based insecticide Ecospray Norfolk UK is seeking registration of a garlic-based insecticide. The company intends to present the compound as an environmentally friendly alternative to conventional insecticides for the control of cabbage root fly. Triple-action pea seed dressing In spring 2002 Syngenta is to introduce a new pea seed dressing Wakil XL which is claimed to achieve greater disease control with only two thirds of the amount of chemical. The product contains three active ingredients one of which fludioxonil is new to peas. The complexity of the mixture is said to lessen the risk of disease resistance.slugs. The results show that feeding by slugs on germinating wheat was reduced by 68% and crop stands were improved by 11%. The material acted as a feeding deterrent only however; no slugs were poisoned. Bayer is marketing the repellency effect of the Secur seed treatments as complementary to the use of its slug baits such as Draza (methiocarb). …Robotic researchers at the University of the West of England are developing a robot termed SlugBot which can move scan detect and collect slugs whilst ignoring stones in laboratory under conditions similar to those found in real agricultural fields (http://www.ias.uwe.ac.uk/ goto.html?slugbot) Mycotoxins from fusaria Aventis has launched a major study to investigate whether mycotoxins from fusaria on cereal ears could cause serious health problems.Fusarium levels have increased significantly following cool and wet summers increases in minimum cultivation and changes in the fungicidal treatment of cereal ear diseases. Regulations have already been introduced in Canada USA and the Netherlands to protect consumers from mycotoxins. Trials running in France and Germany since 1994 to develop integrated control strategies have now been introduced to the UK with the cooperation of the agrochemical distributor Agrovista. The introduction of late sprays of strobilurin fungicides such as azoxystrobin has removed competing diseases from cereal ears allowing fusaria to flourish. Aventis will be testing their prochloraz fungicide in the control strategy.Carboxin a double mechanism against Fusarium Carboxin the first systemic fungicide introduced by Uniroyal in the 1960s is still used widely today. A formulation based on carboxin plus thiram is effective against Fusarium on wheat. In tests with fludioxonil as reference standard only carboxin-containing formulations reduced internal infection of Fusarium species and gave better results in the field where Pythium was also present. In other research carboxin was found to play a protective role against the effects of proteins induced by fungal attack. (Proceedings of the Third BCPC International Symposium Wishaw UK 2001). DOI 10.1039/b108595f Formulation …slug pellet formulation According to manufacturer De Sangosse in France growers in the UK are missing the point when it comes to choosing between slug pellet products.The key to success it claims is product performance driven by formulation more than active ingredient. De Sangosse is the supplier of metaldehydebased Metarex. More than 40% of UK growers use lowest-cost products mainly mini-pellets. This is in contrast with France the world’s largest slug pellet user. In France Metarex holds a dominant market share on the back of superior technical performance lower cost and a better environmental profile. The UK is the world’s second largest slug pellet market typically 10,000 tonnes for 1 M ha costing £10 M. …organic polymeric nanoparticles as controlled-release adjuvants Wood pressure-treated with tebuconazole and chlorothalonil fungicides in 100-200 nm particles of polyvinyl pyridine and polyvinyl pyridine-styrene had a prolonged resistance to fungal attack.It is believed that this technology could be adapted to give controlled release of other agents such as corrosion inhibitors insecticides and antioxidants. (P Heiden et al. J. Appl. Polym. Sci. 2001 79 458-65). …seed coating technology Landec Ag is proceeding with the development and marketing of its proprietary Intellicoat seed coating technology. Positive trial acceptance of the company’s seed coating products and greater demand for its first commercially available Pollinator Plus seed coating has led the company to consolidate and move its seed coating operations to a new unit in Oxford IN.The seed coatings are designed to regulate the uptake of water and thus germination. The use of Landec’s Intellicoat technology will increase crop yields and extend a farmer’s planting window. The 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. coatings are being applied first to corn canola and soybean seeds. …agrochemical waxes Clariant manufactures wax products for the agrochemical industry (Licowax Ceridust and Agrocer).The company’s Licowax line contain montan and polyolefin waxes in flakes or powder form while micronised waxes make up the Ceridust line which are produced on montan or polyolefin bases in a particle size between 5 and 15 mm. Licowax and Ceridust may serve as built-in raw materials in crop protection formulations and sold in solid form whereas the Agrocer series consists of aqueous wax dispersions formulated as adjuvants for tank mix applications. Agrocer dispersions speed up the plant’s absorption of the active substance making them ideal for systemic pesticides. Licowax and Ceridust provide rainresistant benefits when included in liquid formulated (EC SC and EW) pesticides.The Agrocer line is beneficial for fertiliser coating and may be used as spray adjuvants. These product lines also reduce the loss of active substances through evaporation reduce phytotoxic effects and enhance distribution of the active ingredients when applied in seed dressings. The formation of a thin layer of wax on the seed eases the passage of seeds in the seed distributor and prevents dusting and the loss of active ingredients. Waxes do not have adverse effects on the germination process and offer slow release effects in fertilisers which waxes protect from dusting clumping and absorbing moisture. New granular IPU formulation For the first time a new formulation of IPU with diflufenican (DFF) will be available in the UK in autumn 2001.As Panther WDG the water-dispersible granules are being introduced to reduce the risk of handling incidents which are potential causes of point source contamination. The granular formulation reduces residues remaining in Pesticide Outlook – October 2001 173 R&D NEWS packs and eliminates the need to triple rinse liquid containers. Biological control …control of heather in New Zealand Heather (Calluna vulgaris) was introduced into New Zealand in the early 1900s in an attempt to establish grouse moors. Unfortunately it spread out of control and threatened several natural species. Work undertaken by CABI Bioscience has shown that the heather beetle (Lochmaea suturalis) is very effective in controlling heather and after intensive evaluations it was introduced into New Zealand where despite volcanic eruptions and infestation with a microsporidian it has been shown to control heather at one of the release sites.…garlic mustard in the USA Garlic mustard (Alliaria petiolata) is a major problem in the USA. A native of Europe the weed is spreading across Northern states out-competing natural species and dominating the understorey of forests. A species of the weevil Ceutorhynchus has been identified as a garlic mustard specific species and it is hoped that it can be introduced within the next 3 years. …Myrothecium verrucaria a new broad leaf herbicide? Valent BioScience has commercialised the extract of Myrothecium verrucaria as a nematicide but USDA-ARS workers have identified a strain that when mixed with oil gives effective control of many broadleaved weeds including morning glory (Ipomoea spp.). (http://www.ars.usda.gov). …researchers at the USDA-ARS Western Regional Research Center in Albany CA are testing the possibility of using menthone against the rice weevil (Sitophilus oryzae) – an important storedgrain pest worldwide.

ISSN:0956-1250    

DOI:10.1039/b108595f

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

BIOTECHNOLOGY NEWS Corn rootworm-tolerant maize Monsanto has announced the development of a new Bt-corn that produces a toxin that is active against the corn rootworm (Diabrotica spp.). The gene (cryIIIB) was developed as part of Monsanto’s collaboration with Ecogen and is at least as effective as insecticides in controlling the pest. Corn rootworm costs US farmers $1 billion a year in crop damage and insecticide costs. In 2000 farmers spent $171 million spraying corn with 8 million pounds of insecticide. Procter & Gamble forced to withdraw GM snack Proctor & Gamble has recalled all its Pringles snacks which were sold in Japan following the discovery that they contained NewLeaf Plus and NewLeaf Y GM potatoes which are authorised for use in the USA but not yet in Japan where an application has been pending since 1998.In April 2001 Japan prohibited all imports of food containing GM products which are not approved and labelling of all those which are approved. Aventis increases StarLink compensation offer Aventis CropScience increased its offer of compensation payments by an undisclosed sum (previous offer amounted to $100 M) to compensate farmers whose crops were contaminated with the GM StarLink maize. StarLink contains the protein Cry9C which has a property also shown by human allergens. GM labelling in the EU The EU Commission proposes to seek the labelling of GM food “from farm to table” with records held at each stage of the food chain and for retail labels to specify the presence of authorised GMs in foodstuffs including animal feed above a 1% threshold.Environmentalists see the proposals as the thin edge of the wedge opening up the EU market to the entry of unauthorised GMs. A clause permitting products to contain up to 1% of modified VISIT OUR WEBSITE Have a look at the Pesticide Outlook Website on http://www.rsc.org/po 174 Pesticide Outlook – October 2001 This journal is © The Royal Society of Chemistry 2001 material passed as safe by the EU Commission but now on hold due to a moratorium on new licences causes particular concern. US traders however see the plan as a trade barrier since trying to keep GM and non-GM soybeans apart would raise prices. Further labelling is unjustified as GM crops do not substantially differ from other crop varieties; to treat them differently violates World Trade Organisation rules.Reduced investment and confidence in GM technology A report published in the Guardian (28 August 2001) has suggested that the growth of GM crop plantings and company investment in research is falling. Nevertheless global plantings are still around 40 M hectares with more than 80% of all plantings in the USA. The lack of enthusiasm of customers and tighter regulation imposed by countries such as Japan and the EU is beginning to cause US maize and soybean growers to reconsider the use of GM crops. The economic rewards are becoming counter-balanced by the lost export markets.Glyphosate-tolerant weeds in Roundup Ready crops? A report in the Kansas City Star (21 August) has suggested that water hemp (Amaranthus tuberculatus) and mare’s tail (Conyza canadensis) have become tolerant of applied glyphosate in Roundup Ready soybeans. Glasshouse trials have shown that about 5% of the water hemp tolerated almost any rate of glyphosate but surprisingly only 5% of the offspring from these survivors withstand treatment. The mare’s tail by contrast is not killed by the herbicide only stunted. GM salt-tolerant tomato A team led by Eduardo Blumwald of the Uinversity of California at Davis has created a salt-tolerant GM tomato. They added a gene which codes for a membranetransport protein called AtNHX1 which pumps sodium into vacuoles.Expression of the transporter gene was increased by adding a ‘promoter’ sequence which they took from the cauliflower mosaic virus. Such GM salt-loving plants could be grown on the large areas of saline land around the world; the removal of salt in this way would also help to clean the soil. Snippets …work being undertaken by Ralph Bock in Munster Germany has been targeted at introducing novel genes into chloroplast DNA. To date the team has been successful in introducing a gene into tomato chloroplasts and has demonstrated the production of high levels of the desired protein. …work at Abertay University Dundee Scotland has produced elm trees that may be resistant to Dutch elm disease. A gene coding for a natural fungicide has been introduced into the trees and these saplings are being grown in glasshouses to a size where their resistance can be tested.Dutch elm disease has destroyed over 25 million elm trees in the UK alone from the late 1960s. …researchers at DuPont’s Pioneer Hi-Bred unit have developed GM corn that is able to resist corn rootworm using endotoxins from Bacillus thuringiensis. …Monsanto is calling for protection for its GM crop field trials after the destruction of a site in Beaumont-sur-Leze France. The group wants the authorities to enforce the law and pointed out the Beaumont-sur-Leze trial was destroyed after the Minister for Agriculture listed field trials planned for 2001. …in July 2001 the new John Innes Genome Centre was opened in Norwich UK. The centre was jointly funded by Syngenta the East of England Development Agency the Biotechnology and Biological Sciences Research Council and the John Innes Foundation (http://www.jic.bbsrc. ac.uk/press/). …transgenic papaya is being developed in Thailand in response to the spread of papaya ringspot virus (PRSV). DO1 10.1039/b108596b

ISSN:0956-1250    

DOI:10.1039/b108596b

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

ENHANCING BIOCONTROL AGENTS Jim Ligon of Syngenta Biotechnology Inc. at Research Triangle Park NC USA reports on a recent NATO workshop Biocontrol the inhibition of a pest by another organism (the biocontrol agent) has attracted interest in recent years as a potential replacement or supplement of traditional chemical pesticides since it is generally regarded as safer for human health and the environment. In mid-June about 50 scientists from 18 countries came together at a NATO-Advanced Research Workshop to discuss important developments in this promising technology. Although there are a few successful biocontrol products on the market today they suffer from the impression that they are less effective than chemical pesticides. A key point of discussion at the workshop was the use of genetic technologies to enhance the activity of biocontrol agents.Although the meeting venue was scenic and enticing (a secluded villa in the Tuscan hills near Florence) the workshop was intense and focused with presentations on many different aspects of biocontrol. and Fusarium while enhancing plant root growth and nitrogen utilization by up to 25%. Don Nuss of the University of Maryland described the development of transgenic viral biocontrols that infect and reduce pathogenicity of Cryphonectria parasitica the casual agent of chestnut blight. Bioherbicides A weakness of some biocontrol agents is that unlike most chemical pesticides they are often active against a narrow range of pests. However David Sands (Montana State University) described the development of a broad-spectrum bioherbicide based on Sclerotinia that infects and kills several key weed species.In order to limit its spread in the environment they isolated a version of Sclerotinia requiring arginine for growth which is added to the formulated spores to preclude the spread of the Sclerotinia in the environment after the death of the weed. Another version overproduces branch-chain amino acids acting like ALSinhibiting herbicides. The group of Alan Watson (McGill University) has focused on the fungus Colletotrichum coccodes a pathogen of velvetleaf. Applied alone Colletotrichum is only partially effective but Watson and his group have discovered that co-inoculation of the fungus with a saprophytic Pseudomonas that grows on leaf surfaces enhances its activity.The bacterium consumes much of the available carbon on the leaf surface forcing the fungus to shorten its saprophytic phase and invade the plant where it is better able to survive. Adding oxalate enhances the early Colletotrichum growth in the leaf. Biofungicides Several interesting findings on the development of biofungicides were presented. Gary Harmon from Cornell University described his work to enhance natural activity by fusing strains of the fungus Trichoderma harzianum the active agent of RootShield. T. harzianum has broad activity against important plant pathogens including Rhizoctonia Pythium This journal is © The Royal Society of Chemistry 2001 Pesticide Outlook – October 2001 175 Enhancement with genetic technology The group of Jonathan Gressel (Weizmann Institute of Science) has been working with a Fusarium that is pathogenic on the parasitic weed broomrape.A transgenic Fusarium that overproduces the plant hormone indole acetic acid was more effective than the wild type. The author of this article described efforts to genetically engineer a Pseudomonas biofungicide to produce more active broadspectrum antifungal metabolites to enhance its activity. There are concerns about the spread of transgenes or transgenic organisms in nature and their potential adverse affects on human health and the environment. Accordingly many presentations included potential strategies to limit the spread of the transgene or transgenic organism in the environment.There are many challenges facing the development of genetically modified enhanced biocontrol agents. Technical Bioinsecticides Several presentations focused on the key area of bioinsecticides. Tariq Butt (University of Wales Swansea) described his work with entomophagus fungi. He described a ‘Push- Pull’ control strategy to attract the insect pests to a sacrificial ‘trap’ crop to concentrate the pest in a smaller area for more efficient treatment with the biocontrol agent. The ability to transport bioinsecticidal nematodes was enhanced by Mike Wilson (University of Aberdeen) by engineering in proteins that allow the organism to withstand transient heat stress. Tom Grigliatti (University of British Columbia) described an interesting new TAC (transposonarmed cassette) approach for the control of insect pests.He is developing P-element transposons that easily spread through the population of a target insect pest and contain an inducible insect-lethal gene that can be activated by a harmless nontoxic chemical to kill the pest during times of severe crop predation. Ray St. Leger (University of Maryland) is using functional genomics to identify genes in the fungus Metarhizium anisopliae that are involved in its insecticidal activity. He is developing an EST database to discover genes that could be enhanced in the fungus to improve its activity. DOI 10.1039/b108607n WORKSHOP REPORT WORKSHOP REPORT hurdles aside there are many problems related to regulatory approval and public acceptance.Julian Kinderlerer of the Institute of Biotechnological Law and Ethics in Sheffield England gave a concise overview of the political legal and societal hurdles to the registration and marketing of genetically modified organisms. He pointed out that the Cartagena Protocol requires the assessment of environmental and health risks of GMOs but not their benefits and does not allow comparisons of new GMO-based technologies with the current practices that they are targeted to replace. This makes it impossible to conduct a valid riskbenefit analysis of GMOs to support their introduction and use. Developers of GMO products are being asked to prove that they pose zero risk to health and environment a standard to which no other new technology has been held.Another threat to biocontrol products is the plethora of dubious unregistered biocontrol products. Since many of these are marketed not as pesticides but as soil amendments ICM/ PEST MANAGEMENT – BLENDING NEW WITH OLD TECHNOLOGIES Hamish Kidd reports on a few highlights from a recent meeting organised by the SCI Crop Protection Group On 11 September 2001 over 40 people met for a conference principally on spray application within the context of integrated crop management (ICM). Paul Hamey from The UK Pesticides Safety Directorate started the meeting with a broad outline of how spray application is regulated in the UK as part of an overall risk assessment approach. The different types of spray equipment nozzle types buffer zones and LERAPs were outlined with special reference to potential spray drift and consequent risk to spray operators and consumers.Buffer zones were a topic returned to later in the conference by Alastair Burn of English Nature who emphasised their value for protection of wildlife. Miles Thomas presented some results from the UK Pesticide Usage Survey – a survey which was started in 1965 and has been carried out ever since on a 3–5 year cycle. The most recent survey of pesticide use in 1999 has shown some important trends. As the more persistent compounds have been withdrawn there has been l A reduction in the range of pesticides applied l A trend towards reduced-rate applications l An increase in the number of applications For example on carrots usage of insecticides and fungicides had increased in intensity with almost 2/3 of all crops receiving more than 3 insecticide sprays almost inevitably lambda-cyhalothrin compared to 37% in 1986 when organophosphate use dominated while fungicide use had changed from an exclusively mancozeb/metalaxyl use to tebuconazole fenpropimorph and metalaxyl-M.Ian Gillott who advises Thames Valley vegetable and salad growers made the point strongly that lack of support for minor-use pesticides was making life very difficult for such growers and he feared for the future of the industry. The reduction in available pesticides was putting reliance on the few remaining compounds with consequent risk of the development of resistance.He made a plea for manufacturers to support minor uses and for the Government to provide funding to develop new molecules. Pressure from the large supermarkets to keep reducing pesticide use while at the same time wanting cosmetically perfect produce was putting an intolerable burden on vegetable and salad growers. Paul Miller pointed forward with a presentation on the use of electronics to reduce pesticide use especially patch spraying for weed control and adjustment of spray delivery to measured canopy characteristics. The message of precision agriculture was echoed by Graham Matthews from IPARC at Silwood Park who also made a plea for reduced spray volumes to maximise the benefits of surfactants and for improved nozzles such as those which are air-assisted.Alan Dewar from IACR Broom’s Barn in Suffolk outlined the potential advantages to be gained by the use of GM herbicide-tolerant sugar beet. These could enable less herbicide to be applied and also enable weeds to be left in the crop for longer with consequent benefits in the control of potato cyst nematodes and volunteer potatoes and also environmental benefits. The SCI Crop Protection Group holds regular meetings for further details see http//:sci.mond.org 176 Pesticide Outlook – October 2001 or plant growth promoting products they do not require stringent regulatory review. Most of these products are ineffective and give effective biocontrol products a bad reputation. Conclusion At the conclusion of the workshop it was clear to all participants that biocontrol is a promising technology that has great potential to produce excellent biopesticide products. The application of genetic technology to enhance biocontrol agents will undoubtedly lead to much better products that will compete successfully with their chemical counterparts. The co-organizers of the workshop Maurizio Vurro and Jonathan Gressel have prepared a book of the proceedings to be published this winter by the IOS Press in the Netherlands.

ISSN:0956-1250    

DOI:10.1039/b108607n

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

GENE FLOW FROM GENETICALLY MODIFIED CROPS Alan Raybould from the Centre for Ecology and Hydrology (Winfrith Technology Centre) at Dorchester UK reports on a controversial issue concerning the field testing of GM crops Currently in the UK there is a programme of ‘Farm Scale Evaluations’ of genetically modified (GM) crops. The programme is designed to compare the effects on biodiversity of GM herbicide tolerant oilseed rape sugar beet and maize with those of conventional varieties of these crops. The evaluations have highlighted concerns about gene flow from the GM plants to conventional crops or wild relatives. Gene flow can also occur over time through seed dormancy. For example seeds of oilseed rape spilled in fields or onto roadsides can survive in the soil and germinate when the ground is disturbed giving rise to volunteer weeds or feral populations.New feral populations of oilseed rape have been found up to 10 years after the variety had been withdrawn from sale. Dispersal and gene flow Gene flow is the movement of genes between populations of a species. In plants gene flow can occur via dispersal of seeds or pollen. However gene flow is more than simply the movement of a seed or a pollen grain; pollen grains must achieve fertilisation and seeds must germinate and produce sexually mature plants. Therefore the presence of GM pollen on the leaves of another plant or GM seed in a batch of non- GM is strictly not gene flow but dispersal. The distinction is important because dispersal without gene flow is a ‘dead end’ for the spread of genes although the consequences of dispersal might be important.For example the presence of GM oilseed rape pollen on organic maize might be regarded as unacceptable “contamination”. However the situation will not continue once the GM oilseed rape is not grown. On the other hand if the GM rape were to pollinate wild relatives then the genetic modification could persist in the environment. Routes for gene flow from GM crops Crop seeds can give rise to plants in a following or neighbouring crop (volunteer weeds) or in semi-natural habitats close to farmland or transport routes (feral populations) (Figure 1). Crops usually cannot persist in semi-natural habitats without continual disturbance and fresh immigration of seed because they are easily overgrown by perennial grasses and shrubs.For example Crawley and Brown (1995) showed that seed spilled from lorries en route to processing plants in Kent rather than self-sustaining populations maintained the presence of oilseed rape populations surrounding the M25. Apart from dispersal associated with agricultural activity pollen generally has a much higher capacity than seeds for bulk long distance dispersal. However as described above to have a lasting effect in the environment pollen must achieve fertilisation. Gene flow through GM pollen can occur to other varieties of the same crop (crop-to-crop gene flow) or to wild plants that are sexually compatible with the crop. This journal is © The Royal Society of Chemistry 2001 Pesticide Outlook – October 2001 177 Variation among crops for gene flow potential Gene flow is to a large extent dependent on the breeding system of the crop (Table 1).Some crops such as wheat and barley are ‘inbreeders’ in which pollen is usually transferred to stigmas of the same plant or even the same flower. These species generally have a low capacity for gene flow. Conversely in ‘outbreeders’ pollination usually occurs by transfer of pollen to stigmas of flowers on a different plant. Many specialised mechanisms exist to promote the transfer of pollen such nectar production to attract pollinating insects. As well as having mechanisms to promote cross-pollination many outbreeders have systems to prevent self-fertilisation.For example pollen and stigmas may ripen at different times or pollen may be prevented from germinating if self-pollination occurs. This latter mechanism is called self-incompatibility. Cabbage is an insect pollinated self-incompatible species and sugar beet and ryegrass are examples of wind pollinated self-incompatible species. Outbreeders have a high capacity for gene flow. A third category of plants has a so-called ‘mixed’ mating system where seeds are set by a mixture of self- and crossfertilisation. Oilseed rape is an example of this kind of plant. The proportion of cross- to self- fertilisation can vary depending on crop variety and environmental conditions and in these species gene flow can occur over long distances.Another factor determining the amount of gene flow is the presence of sexually compatible wild relatives near to the crop. Again three categories can be defined (Raybould and Gray 1993). A group of crops with no compatible wild relatives in the UK such as maize and potato have a minimal risk of gene flow to wild species. Some crops sugar beet and ryegrass for instance have wild relatives that are essentially the same species. Here the likelihood of gene flow from crop to wild relative is high. Finally there is an intermediate group of crops that have local wild relatives of the same genus. In the UK oilseed rape (Brassica napus) has several wild relatives of the same species such as wild DOI 10.1039/b108604a GM CROPS Figure 1. A feral population of wheat which probably established from wheat straw used to stabilise the sides of the GM CROPS Table 1.Examples of UK crops with different potential for gene flow to other crops or wild relatives Crop Potato Mixed Cultivated species are self- (Solanum tuberosum) compatible but crossing can occur via insect pollinators Maize (Zea mays) Wheat (Triticum aestivum) Barley (Hordeum vulgare) Oilseed rape (Brassica napus) Linseed Mixed Self-compatible but crossing Pale flax (L. bienne) perennial flax (L. perenne) (Linum usitatissimum) can occur via insect pollination Ryegrass (Lolim perenne) Sugar beet (Beta valugaris) †See Scheffler & Dale (1994) for a detailed review of gene flow from oilseed rape cabbage (Brassica oleracea) (Figure 2) and wild turnip (Brassica rapa).This group of crops can transfer genes to road cutting 178 Pesticide Outlook – October 2001 Breeding system Mixed Usually self-compatible but cross pollination promoted by having separate male (tassel) and female (silk) inflorescences Inbreeding Inbreeding Mixed Self-compatible but but crossing can occur via insect and wind pollination Outbreeder self-incompatible wind Many e.g. species of Lolium & Festuca pollinated Outbreeder self-incompatible mainly wind pollination though insects may act as pollinators Potential for gene flow Wild relatives in the UK Low crop-to crop Minimal to wild relatives Woody nightshade (Solanum dulcamara) no hybrids produced even with artificial pollination None Crop-to-crop gene flow over distances <200 m Minimal to wild relatives None Very low crop-to crop Minimal to wild relatives Many wild Hordeum species but none known Low crop-to crop to hybridise under natural conditions Low to wild relatives Can cross naturally with Brassica rapa (wild Moderate-high crop-to-crop turnip).Unconfirmed reports of natural crosses Moderate to wild relatives with Brassica oleracea (wild cabbage). Can be made to cross with several other wild Brassica species under laboratory conditions Many other species of Brassica & related genera (e.g. Raphanus [radish]) with various degrees of compatibility† Moderate crop-to-crop Low to wild relatives and fairy flax (L.catharticum). No hybrids with linseed recorded in the UK High crop-to-crop and to wild relatives High to weed beet and sea beet Weed beet – plants that flower (bolt) before harvest Sea beet (Beta vulgaris ssp. maritima) can cross with bolters in the beet crop wild relatives but with low and variable frequency that is hard to predict (e.g. Wilkinson et al. 2000). Consequences of crop-to-crop gene flow Crop-to-crop gene flow from GM crops has already had serious consequences in North America. One incident involves a variety of maize called StarLink. This variety has been genetically modified with a gene from a soil bacterium Bacillus thuringiensis. The product of the gene a protein called Cry9C protects the maize against insect pests such as the European corn borer.The US Environmental Protection Agency restricted the commercial use of this variety to animal feed and industrial use; the variety was not approved for human consumption because of concerns that the Cry9C protein might be allergenic. Last year DNA from StarLink was detected in taco shells and the manufacturer voluntarily recalled the affected products. Eventually the US Food and Drug Administration officially recalled the taco shells and many other manufacturers of foods containing maize also recalled products. The initial contamination problem seems to have been Figure 2. A population of wild cabbage a relative of oilseed rape growing on limestone cliffs at St. Aldhelm’s Head on the coast of Dorset. due to mixing of seed before or during processing.However there are several reports of the gene for Cry9C being detected in other maize varieties. It seems likely therefore that gene flow has occurred from StarLink to other maize varieties and may also have played a part in the contamination of the maize used to make the taco shells (e.g. Ellstrand 2001). The company that sold StarLink agreed to pay farmers for StarLink maize and other varieties that had become contaminated with StarLink if the maize was not destined for animal feed. The incident has raised questions about food labelling and liability in cases where GM and non-GM varieties are accidentally mixed. A second problem that arose because of crop-to crop gene flow was the development of volunteer oilseed rape that was resistant to 3 herbicides.In Alberta in 1997 a farmer sowed part of a field with a GM oilseed rape resistant to glufosinate; in the remainder he planted a conventional variety resistant to imidazolinone. In an adjacent field he planted a GM oilseed rape resistant to glyphosate. The following year the farmer grew imidazolinone resistant rape in the field that had the glyphosate resistant rape the previous year and left the other field fallow. In this field he tried to control volunteer rape weeds with glyphosate but without success. Hall et al. (2000) found that the glyphosate resistant weeds were also resistant to either imidazolinone or glufosinate. This indicated that gene flow via pollen rather than seed movement was the source of the resistant volunteers.In addition two volunteers gave progeny resistant to all three herbicides; the imidazolinone rape crop had probably crossed with a glufosinate and glyphosate resistant weed. Hall et al. (2000) point out that this situation should be avoided by not growing varieties with different herbicide resistance mechanisms so close together. In addition herbicides with a different mode of action should be used to control volunteers. Consequences of crop to wild relative gene flow The hazards of crop-to-crop gene flow are fairly clear adulteration of harvested seed and novel traits in volunteer GM CROPS weeds. There is less agreement about the hazards of gene flow to wild relatives. Some people have ethical concerns considering gene flow to wild plants to be ‘genetic pollution’ (Daniels and Sheail 1999).Other hazards are the potential for changes in the persistence abundance or distribution (‘weediness’) of wild relatives which might alter the composition of plant communities and effects on other (‘non-target’) organisms. It is difficult to generalise about the traits that make a plant a successful weed. Several attempts have been made but none is very successful (e.g. Gray 1986 and Williamson 1993 for the problems involved). Unfortunately this means that risk assessments must proceed on a case-by-case (crop and modification) basis at least until more data are available. It is likely that herbicide tolerance will not increase the weediness of plants in non-agricultural habitats where herbicides are not applied.Crawley et al. (2001) sowed seeds of GM herbicide resistant potato oilseed rape maize and sugar beet along with non-GM controls in 12 seminatural habitats throughout the UK. For all GM crops recruitment was very low (<4% of seed sown) and in no case was it greater than conventional controls. All populations were extinct after 4 years except one non-GM potato that still persists after 10 years. Traits that are more likely to change the weediness of plants are resistance to physical stresses such as drought salinity high temperature and pollution. Resistance to pests and diseases may also increase weediness if the size of plant populations is controlled by these factors.Up to a point laboratory experiments may help to predict the environmental impacts of resistance genes. Suppose that in an experiment a GM plant with insect resistance produces more seed than a non-GM plant when attacked by insects it does not follow that the GM plant will become a worse weed. Factors other than insects might be much more important in controlling seed output in the field. Also seed output might not be a factor limiting the size of a population so although resistant plants produce more seed the population size does not increase because the previously susceptible population produced sufficient seed to keep the population at its carrying capacity (e.g. Bergelson 1994). However while the size of the population may not change its genetic composition may change from susceptible plants to resistant ones which could have a knock-on effect on non-target insects.Non-target effects occur when for example a gene for resistance against a pest or disease has detrimental effects on harmless or beneficial organisms. Laboratory experiments have shown that ladybirds feeding on aphids feeding on GM insect resistant potatoes show lower survival and fecundity than ladybirds feeding on aphids on conventional potatoes (Birch et al. 1999). Similar results have been found with green lacewings fed with European corn borer larvae reared on GM insect resistant maize. It must be remembered that laboratory experiments are usually ‘worst case scenarios’ because the predator species has no choice over its food.In addition the effects tend to be compared with ‘no treatment’ rather with insecticide or other control methods that the GM crop might replace. Pesticide Outlook – October 2001 179 GM CROPS However laboratory experiments do provide a useful guide to variables that should be measured in field experiments. Conclusions Crop-to-crop gene flow has already had serious consequences for agriculture. For seed crops which require pollination it is unlikely that unwanted gene flow between crops could be avoided. The degree of separation (in space or time) between GM and non-GM crops will depend upon the permitted thresholds for extraneous gene flow agreed by regulators and other interested parties. Wider environmental impacts are harder to predict as the population dynamics of species are controlled by many interacting factors.Field trials guided by laboratory experiments are required to assess these risks. References Bergelson J. (1994) Changes in fecundity do not predict invasiveness – a model study of transgenic plants. Ecology 75 249-252. Birch A. N. E.; Geoghegan I. E.; Majerus M. E. N.; McNicol J. W.; Hackett C. A.; Gatehouse A. M. R.; Gatehouse J. A. (1999) Tri-trophic interactions involving pest aphids predatory 2-spot ladybirds and transgenic potatoes expressing snowdrop lectin for aphid resistance. Molecular Breeding 5 75–83. Crawley M. J.; Brown S. L. (1995) Seed limitation and the dynamics of feral oilseed rape on the M25 motorway. Proceedings of the Royal Society of London Series B 259 49–54.Crawley M. J.; Brown S. L.; Hails R. S.; Kohn D. D.; Rees M. (2001) Transgenic crops in natural habitats. Nature 409 682–683. PREVIOUS PESTICIDE OUTLOOK ARTICLES ON GM CROPS How to engineer a crop plant (Dunwell) – Pesticide Outlook 1998 9(4) 29 GM crops – is there a future? (Halford) – Pesticide Outlook 1999 10(6) 246 Farm scale evaluations of GM crops (Firbank) – Pesticide Outlook 2001 12(3) 116 Bt maize and monarch butterflies (McLaren) – Pesticide Outlook 2001 12(4) 136 Do GM crops mean less pesticide? (Benbrook) – Pesticide Outlook this issue p. 204 180 Pesticide Outlook – October 2001 Daniels R. E.; Sheail J. (1999) Genetic pollution concepts concerns and transgenic crops. In Gene Flow and Agriculture – Relevance for Transgenic Crops.Farnham British Crop Protection Council. pp. 65–72. Ellstrand N. C. (2001) When transgenes wander should we worry? Plant Physiology 125 1543–1545. Gray A. J. (1986) Do invading species have definable genetic characteristics? Philosophical Transactions of the Royal Society of London Series B 314 655–674. Hall L.; Topinka K.; Huffman J.; Davis L.; Good A. (2000) Pollen flow between herbicide resistant Brassica napus is the cause of multiple-resistant B. napus volunteers. Weed Science 48 688–694. Raybould A. F.; Gray A. J. (1993) Genetically modified crops and hybridization with wild relatives – a UK perspective. Journal of Applied Ecology. 30 199–219. Scheffler J. A.; Dale P. J. (1994) Opportunities for gene transfer from transgenic oilseed rape (Brassica napus) to related species. Transgenic Research 3 263–278. Wilkinson M. J.; Davenport I. J.; Charters Y. M.; Jones A. E.; Allainguillaume J.; Butler H. T.; Mason D. C.; Raybould A. F. (2000) A direct regional scale estimate of transgene movement from genetically modified oilseed rape to its wild progenitors. Molecular Ecology 9 983–991. Williamson M. (1993) Invaders weeds and the risks from GMOs. Experientia 49 219–224 Alan Raybould is head of the Molecular Ecology Group at CEH Dorset. His research is focussed on predicting the impact of gene flow from genetically modified crops to their wild relatives. His main interest is the effects of plant secondary chemistry on disease and pest resistance.

ISSN:0956-1250    

DOI:10.1039/b108604a

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

International Award for Research in Agrochemicals Ralph O. Mumma was presented with this award sponsored by DuPont Agricultural Products Company on Monday August 27 2001 for his research contributions in environmental quality chemical ecology and biochemistry. Dr. Mumma’s award address which had the eye-catching title of “Don’t Tread on Me” examined his research on mite damage in geraniums (Pelargonium � hortorum). Eighteen years of research comparing insect-resistant and susceptible geraniums ultimately showed that the glandular trichome exudates from only resistant varieties contained specific unsaturated fatty acids leading to unsaturated alkyl anacardic acids responsible for resistance. Thus the title of the talk represented a message from resistant geraniums to mites to stay off! The symposium which followed the award was organized by Jeanette Van Emon U.S.EPA and Terry Spittler Cornell University. It was composed of three sections each representing an aspect of Mumma’s contributions l chemicals associated with host-pest interactions producing such effects as signaling for pest predators suppressing a plant’s natural defense system and serving to reciprocally stimulate evolutionary responses. l agrochemical fate in the environment as well as in cellular systems including phytoremediation as a means to reduce residue availability the potential for human exposure to agrochemicals in urban environments use of cell cultures to study metabolic fate and the likelihood that pesticides affect hormone signaling pathways rather than receptor molecules.l immunochemistry and its use in analysis looking at the introduction of this technology to the field of pesticide chemistry as well as other agriculturally related disciplines. Sterling B. Hendricks Memorial Lectureship Award On Tuesday August 28 2001 Malcolm J. Thompson was presented the Sterling B. Hendricks Memorial Lectureship Award given by the Agricultural Research Service (ARS) U.S. Department of Agriculture (USDA) and sponsored by the Division of Agrochemicals ACS. This award was established by ARS in 1981 to honour the memory of a great scientist by recognizing scientists who have made outstanding contributions to the chemical science of agriculture. DOI 10.1039/b108610n AMERICAN CHEMICAL SOCIETY HONOURS RALPH MUMMA AND MALCOLM THOMPSON Nancy Ragsdale of the United States Department of Agriculture (USDA) reports on awards for outstanding research contributions made at the Fall Meeting of the American Chemical Society in Chicago Pesticide Outlook – October 2001 181 This journal is © The Royal Society of Chemistry 2001 Born in Carlisle PA in 1934 Ralph Mumma spent his entire professional career at The Pennsylvania State University.In 1990 he was named Distinguished Professor of Environmental Quality. In 1997 the Ralph O. Mumma Professorship in Entomology was established at Penn State in his honour. Since retiring he has been on the staff at Exygen Research located in State College PA. Ralph has been an active member in several professional societies and has served as treasurer of the Division of Agrochemicals ACS since 1995.Presenting the Award Adrianna Hewings Director of the ARS Midwest Area on behalf of the ARS Administrator Dr. Floyd Horn highlighted how Mr. Thompson’s contributions in agricultural chemistry have influenced many diverse disciplines including biochemistry entomology plant physiology pharmacology parasitology and nematology. Dr. Hewings highlighted a number of accomplishments from Thompson’s research that were not mentioned in his award address. He was instrumental in identifying epoxy methyl farnesoate the predominant developmental hormone in insects leading to a new generation of environmentally sound pesticides including methoprene and hydroprene.In the field of plant biochemistry Thompson made a major contribution by successfully synthesizing the first highly active analogs of the plant hormone brassinolide. Prior to this development large scale testing of such compounds was impossible due to the complexity of the chemical. This work AWARDS had international impacts and commercial development of these compounds as plant growth enhancers continues. Mr. Thompson is probably best known for his research related to insect ecdysteroids. For his award address he chose to speak on “Structure Function and Metabolism of Insect Steroids”. Insects require a dietary source of sterol for normal growth metamorphosis and reproduction. Many plant-feeding insects convert phytosterols to cholesterol which in turn is used in synthesis of ecdysteroids which are involved in molting.By understanding the process of molting inhibitors can be developed that interfere with the manner in which insects metabolize sterols and thus inhibit growth and development in immature insects. Following a reception in Thompson’s honour a symposium featured speakers giving papers related to chemistry associated with pest-plant interactions. These addressed nematode metabolism of plant sterols whitefly-pathogenhost plant interactions rapid plant cell division promoted by weevil-produced bruchins and enzyme targets in sterol synthesis as potential sites of inhibition for drug design and bioengineered resistance. Nancy Ragsdale is National Program Leader for Pest Management Chemistry and Toxicology Agricultural Research Service United AWARDS Born in Baldwin Louisiana in 1927 Malcolm Thompson has held a series of U.S.government civilian jobs as a chemist beginning with the U.S. Dept. of Interior followed by the National Institutes of Health the U.S. Army Chemical Center and ultimately ARS/USDA. He has received numerous awards including induction into the ARS Science Hall of Fame in 1994 and election as a Fellow of the American Association for the Advancement of Science in 1967. States Department of Agriculture (USDA). l l l l l l ACS AGROCHEMICALS DIVISION The next ACS National Meeting will be held in Orlando Florida April 7–11 2002. The Agrochemicals Division program will include symposia on the following l Applications of Accelerator Mass Spectrometry to Biomedical and Environmental Research Chemistry and Toxicity of Pesticides and Related Products in Accidental Fires Innovative Analytical Techniques for Residues in ppb Concentrations Synthesis and Chemistry of New and Potential Agrochemicals HPLC/MS as Applied to the Analysis of Agrochemicals International Award for Research in Agrochemicals (Cosponsored with BASF) Young Scientists Recognition Award (Sponsored by Dow Agrosciences and Co-sponsored by the ACS Younger Chemists Committee) General Papers (Cosponsored with Fertilizer SubDivision of AGRO) l For more information on the ACS Agrochemicals Division see http://membership.acs.org/A/AGRO/ 182 Pesticide Outlook – October 20

ISSN:0956-1250    

DOI:10.1039/b108610n

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

ADJUVANTS FOR AGROCHEMICALS Alan Knowles of FORM-AK Formulation Consultancy Services Tonbridge UK reports on the 6th International Symposium on Adjuvants for Agrochemicals (ISAA 2001) held in Amsterdam from 13–17 August 2001 This symposium was the sixth in a series of symposia which began in 1986 at Brandon Manitoba (Canada). Further symposia have been held every 3 years in Blacksburg Virginia (USA) Cambridge (UK) Melbourne (Australia) and Memphis Tennesee (USA). About 340 delegates attended the symposium from all over the world. Over the last few years the number of scientists working on adjuvants in academic institutions has been decreasing while the interest of agrochemical companies and adjuvant suppliers in the potential benefits of adjuvants has been increasing.Another trend is that in the past the use of adjuvants was concentrated on herbicides whereas there is now considerable interest in using adjuvants for fungicides and insecticides to enhance activity and possibly reduce dose rates for application. There is still considerable development of new adjuvants for the enhancement of glyphosate formulations. Research on adjuvants to control drift and volatilisation is another challenging area for reducing dose rates and wastage of active ingredients. Opening addresses Dale Steichen of Akzo Nobel Sweden gave an overview of the agrochemical and surfactants industries which he called “The Matched Pair”. It is estimated that the agrochemical industry consumes over 350,000 tonnes of surfactants and it is essential for the surfactants industry to understand the needs of the agrochemical industry for formulated products as well as for tank mix adjuvants.Examples of formulation development are the need to move from solvent-based formulations containing Volatile Organic Compounds (VOC’s) towards water-based emulsions and microemulsions requiring specialised surfactants. The second opening address was given by Jeff Graham of Monsanto USA. Dr Graham concentrated on the use of glyphosate formulations particularly for overspraying on genetically engineered crops (Roundup Ready crops). Glyphosate is the largest-selling herbicide in the world with total estimated sales of about US$ 3 billion. This figure is larger than the next 10 herbicides in the world combined.Many formulations using different salts of glyphosate and a variety of adjuvants are now available from agrochemical companies around the world. Herbicidal activity is not an issue but Dr Graham warned of the potential crop safety effects with some formulations on GM crops. DOI 10.1039/b108611c This journal is © The Royal Society of Chemistry 2001 Pesticide Outlook – October 2001 183 Trends in methodology and chemistry The use of adjuvants to enhance the activity of fungicides is becoming more popular. Johan Rommens (Uniqema Belgium) described the alkylpolysaccharides which reduce the ‘effective surface tension’ giving improved retention on leaves. These adjuvants can reduce the dose rates of 1 For a full list of List 4 inert ingredients see http://www.epa.gov/oppr001/inerts/list4inerts.html CONFERENCE REPORT Wetting and uptake A number of speakers discussed research into understanding the mode of action of adjuvants.It is essential for the spray droplets to wet the leaf surfaces and sometimes organosilicones are used as ‘Superspreaders’. Dynamic surface tension is an important parameter but surface elasticity of the droplets should also be taken into account. Furthermore uptake of the active ingredient into the plant is a function of the concentration on the leaf. Therefore too much spreading may reduce uptake into the plant. Rain dew or irrigation on the crop can affect redistribution and uptake of the active ingredient. Solvency effects from oil-based adjuvants are also important in terms of biological efficacy.Regulatory and environmental Adjuvants can be built into the formulation or added as a tank mix. They may constitute up to 30% of the pesticide formulation. In the USA adjuvants are controlled by EPA and are subject to tolerance limits. The safest adjuvants are placed on List 4a1 if they are food-like materials or List 4b if the materials are believed to be safe. However in Europe the registration system is not yet clearly defined and is not covered by Directive 91/414/EEC. Most European countries require a separate hazard assessment of each adjuvant. Biological performance Adjuvant performance can be affected by weather and UV light effects product formulation spray application and plant biology.These factors were discussed by Jerry Green (Du Pont USA). As much as 80–85% of the pesticide can be lost during spraying of which spray drift may account for 15% rebound 30% and run-off 20%. Robyn Gaskin (Forest Research New Zealand) said that in some cases pesticide dose rates can be reduced by 50–60% using organosilicone ‘superspeaders’. CONFERENCE REPORT strobilurin fungicides. Alkoxylated triglycerides were discussed by Cognis while Huntsman recommended shortchain alkylene carbonates to increase the solvent power of conventional ethoxylated surfactant adjuvants. Clariant International have developed a range of waxes which have film-forming properties to reduce evaporation and improve rainfastness. Microemulsions can also be considered as water based formulations containing a high concentration of emulsifying and bioenhancing surfactants.Glyphosate targeting OSi Specialties USA have developed blends of trisiloxane alkoxylate with tallow amine ethoxylates which have been shown to enhance the activity of glyphosate on certain weeds. Victorian Chemical Company Australia have developed homogenous liquid compositions incorporating several desirable but physically incompatible adjuvant components such as oil based adjuvants and aqueous ammonium salts. Several glyphosate products containing built-in adjuvants have also been developed by a novel method which is now part of a patent application. Dr Feng (Monsanto USA) examined the possible problems of crop safety when different salts of glyphosate acid are sprayed onto Roundup Ready crops.Water hardness and water temperature can also be important factors in glyphosate efficacy. Drift and vapour management Losses due to spray drift are a serious economic and environmental problem. Andrew Hewitt (Stewart Agricultural Research Services USA) said that the performance of adjuvants in relation to spray formation droplet movements deposition and coverage depends on the physical properties of the product interactions with other tank mix additives and the spray nozzle design. A Spray Drift Task Force has been set up to examine all of these effects and in many cases the droplet size range for several nozzles can be predicted by a model called ‘DropKick’.Air induction nozzles can improve spray targeting and reduce drift. PREVIOUS PESTICIDE OUTLOOK ARTICLES ON FORMULATIONS Use of surfactants for pesticide formulations (Knowles) – Pesticide Outlook 1995 6(3) Biologically optimised agrochemical formulations (Stock) – Pesticide Outlook 1998 9(1) 21 Improved insecticides through encapsulation (Perrin) – Pesticide Outlook 2000 11(3) 68 Adjuvants for agrochemical formulations (Green) – Pesticide Outlook 2000 11(5) 196 184 Pesticide Outlook – October 2001 Future outlook New research work is taking place to use adjuvants in novel ways such as inducing insects to absorb more insecticide by feeding or to spray foams to mark the limits of crop treated areas during spray application. A totally novel area of adjuvant use was presented by Wim Hennick (Utrecht University) in which methacrylate based polymers are used as non-viral gene carriers to deliver DNA cells for genetic modification.The symposium ended with an overview of the agrochemical and adjuvants markets and likely future trends from Allen Underwood (Helena USA). The global agrochemical market is estimated at US$ 31 billion and the global adjuvants market at US$ 1 billion. The USA is the major market for agrochemicals (ca.25%) and adjuvants (ca. 40%). The use of adjuvants will become more important in the future as companies try to enhance the activity of pesticides and reduce dose rates. The restructuring of agrochemical companies and the influx of generic products will dramatically impact the agrochemical and adjuvant markets particularly with glyphosate but increasingly also with fungicides and insecticides. Alan Knowles has been consulting since 1992 in new formulations surfactants and adjuvants for the agrochemical industry. He is also a United Nations consultant with experience in developing countries in Asia and Africa. Alan edited a book entitled Chemistry and Technology of Agrochemical formulations published by Kluwer Academic Publishers Netherlands in 1998. For more details of his consultancy services visit his new website at http://www.form-ak.com

ISSN:0956-1250    

DOI:10.1039/b108611c

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

Introduction The diamondback moth (DBM) Plutella xylostella has become a major insect pest both in Australia and around the world. It can have devastating effects on Brassica vegetable crops such as cabbage cauliflower broccoli Brussels sprouts and Asian leafy brassicas. It can also cause significant damage in canola and forage turnips. AUSTRALIA LEADS THE WAY IN THE FIGHT AGAINST THE DIAMONDBACK MOTH fight against a major horticultural insect pest Richard Vickers from CSIRO Entomology and Nancy Endersby and Peter Ridland from Institute for Horticultural Development Victoria (all from Australia) describe the latest international efforts in the The larvae eat many small holes in the leaves of the host plants often leaving the leaf epidermis intact making a ‘feeding window’.Most damage is caused by the larvae tunnelling into the heads of plants such as cabbage and Brussels sprouts. They also cause contamination of produce by pupating inside broccoli florets and cauliflower curds. Seedlings of cruciferous forage crops and canola may be destroyed by this pest and severe defoliation or pod grazing may reduce canola yield. This journal is © The Royal Society of Chemistry 2001 Pesticide Outlook – October 2001 185 Biological control Several species of wasp parasitoid were released in Australia in an attempt to biologically control this pest during the 1940s and 1950s and although some species (especially the ichneumonid wasps Diadegma semiclausum and Diadromus collaris) are still present today control has not been achieved.CSIRO Entomology has embarked on a biological attack against this pest using the insect’s own sex pheromone as an agent of destruction. Insecticide resistance In Australia resistance to synthetic pyrethroid insecticides has been identified in DBM populations from vegetable growing areas in all states and resistance to organophosphate insecticides has been identified in some states. AIRAC (AVCARE’s Insecticide Resistance Action Committee) in consultation with researchers devised a twowindow insecticide resistance management strategy for DBM in 1997. By late 1998 fipronil and chlorfenapyr had both been registered for control of DBM and so the twowindow strategy was launched to growers around Australia. The strategy is reviewed regularly and is updated as new products become registered.Four products are currently partitioned into the two-window strategy. In southern Australia (NSW VIC TAS and SA) Secure® (chlorfenapyr) and Success® (spinosad) may be used from 1st September to 31st January whereas Regent® (fipronil) and Proclaim® (emamectin benzoate) may be used from 1st February to 31st August. The national insecticide resistance monitoring program was established in 1999. The program involves testing of field populations of DBM from each state with a variety of new and long-established insecticides. The data collected provide valuable insights to all facets of the industry on the progress of the insecticide resistance management strategy. Biology The moth lays pale yellow eggs 0.5 mm long both singly and in clusters on the stems and both sides of the leaves.One female moth may lay more than 150 eggs during her lifetime. The larvae are grey-green with a dark head in the first three instars and green with a greenish brown head in the final instar. The first and some second instar larvae tunnel inside the leaf while subsequent instars feed on the underside of leaves or tunnel into the plant. The larvae which grow to approximately 12 mm in length may drop to the ground on silken threads if disturbed. They can also wriggle backwards rapidly across the leaf surface. Pupation occurs in an open-mesh cocoon. The adult is a small moth about 10–12 mm long the male being dark brown with a pattern of three consecutive white diamonds on its back and the female moth tan-coloured with less distinct diamond patterns than those of the male.Adults are active at dusk and throughout the night but if plants are disturbed during the day the moths will be seen flying from their resting places. The life cycle of DBM is illustrated in Figure 1. Figure 1. The life cycle of the diamondback moth (Plutella xylostella). DOI 10.1039/b108598k BIOLOGICAL CONTROL The trials proved highly successful. Evidence of infection having spread to the wild population was apparent two days after release of the adults and within five weeks the BIOLOGICAL CONTROL NATIONAL DIAMONDBACK MOTH PROJECT Promotion of crop scouting to the Australian Brassica vegetable industry is a major initiative of the National Diamondback Moth project funded by Horticulture Australia Ltd.In each state project members provide training days and ongoing support to crop scouts. Information gained by crop scouting is essential for making strategic pest control decisions and is fundamental to implementation of IPM. Other aspects of strategic chemical use such as setting up spray rigs to achieve good coverage using label rates and avoiding tank mixes of multiple insecticides have been promoted. Reducing pest pressure through non-chemical management practices is also recommended and includes using clean seedlings destruction of crop residues growing vigorous plants to resist pests and diseases and using crop breaks to reduce DBM numbers and levels of insecticide resistance.Further projects aimed at improving IPM include investigations of l Susceptibility of DBM populations from all states to the newlyregistered insecticides (national insecticide resistance monitoring program for DBM) l DBM movement between vegetable crops and other host plants. l Enhancement of natural enemies of DBM by providing refuge areas and nectar sources l Innovative control tactics (dissemination of biocontrol agents on seedlings and choosing less susceptible cultivars) The national project is led by Greg Baker of the South Australian Research and Development Institute (baker.greg@saugov.sa.gov.au). Project members come from the following organisations South Australian Research & Development Institute; DNRE Institute for Horticultural Development Knoxfield Victoria; NSW Agriculture; University of Adelaide; Department of Primary Industries Water and Environment Tasmania; Department of Agriculture Western Australia; and Queensland Department of Primary Industries.Autodissemination involves the use of pheromone baits (sex attractants) to lure males into inoculation chambers containing a pathogen such as a fungus. Here the males become infected and on returning to the crop disseminate the pathogen amongst their own population. In other words they disseminate the control weapon automatically. In the case of DBM the control weapon is a naturally occurring fungal pathogen Zoophthora radicans. The concept has been tested during various laboratory and small-scale field trials but until recently has not been tested on a scale large enough to demonstrate that it has real potential as a control technique.With this in mind Dr Richard Vickers from CSIRO Entomology collaborated with Dr Judith Pell from the Institute of Arable Crops Research (IARC) at Rothamsted (UK) to conduct proof-of-concept trials. Their aim was to determine whether the fungus could be artificially introduced to a DBM-infested broccoli crop early in the season by releasing laboratory-infected adults. This was seen as an essential pre-cursor to trials in which the fungus would be dispersed via pheromone-baited inoculation chambers the auto-dissemination technique. 186 Pesticide Outlook – October 2001 mortality rate amongst all larvae and pupae was 80%.Amongst mature larvae it was even higher at 93%. During the trials the scientists were also able to demonstrate that the fungus was transmitted aerially as well as by direct contact which augers well for its transmission in low density populations where direct contact of infected and healthy individuals would be minimal. Trials to demonstrate that pheromone-baited inoculation chambers are an effective means of initiating disease are now required. If such trials prove successful then the effect of DBM population density on the development of the fungal disease the design of efficient inoculation chambers and a cost-effective and practical means of producing and storing the fungus will need to be investigated.The issue of low DBM population densities at the beginning of the growing season influencing transmission rates may not be critical as most of the fungal infections appear to be aerially transmitted with little reliance upon healthy larvae physically contacting infected individuals. In addition where low-density populations are involved a greater proportion of adult males will be attracted to inoculation stations by the pheromone baits thus helping to promote fungal development. Outlook Further research will be necessary before autodissemination can be added to the suite of tools needed by growers to combat this devastating pest. CESAR DIAMONDBACK MOTH PROJECTS CESAR (Centre for Environmental Stress and Adaptation Research) has two projects in progress looking at molecular genetic aspects of diamondback moth (DBM).One project based at Monash University aims to characterise molecular genetic markers such as microsatellites for investigation of population structure and moth movement. Markers will be used to identify genetic differences between and within geographically diverse Australian populations of DBM. They will help to determine whether specific moth populations are isolated or connected to others through dispersal. The information gained will enhance our understanding of pest population dynamics and thereby improve management decisions aimed at minimising the development and spread of insecticide resistance. The second project is based at the University of Melbourne and is investigating the molecular basis of resistance to the bacterial insecticide Bacillus thuringiensis (Bt) in DBM.The project aims to identify and map the genes conferring resistance to Bt as well as examining the extent and potential rate of spread of Bt resistance throughout Australian populations of DBM. Knowledge of the resistance mechanisms and underlying genes may allow resistance development to be predicted and minimised as well as giving an opportunity to control the spread of resistance and reduce its effects. CESAR is led by Professor Ary Hoffmann of La Trobe University in Victoria. The Centre aims to understand the main issues and mechanisms involved with adaptation of organisms to stress using experimental model systems and to disseminate this information to industry and the community.Further reading Talekar N. S.; Shelton A. M. (1993). Biology ecology and management of the diamondback moth. Annual Review of Entomology 38 275–301 (can be viewed on the web at http://www.nysaes.cornell.edu/ent/dbm/ under Literature Review Article) Websites http://www.sardi.sa.gov.au/crops/entomolo/dbmipm/ aus_dbm_ipm.html http://www.ento.csiro.au/research/pestmgmt/IPMModellingNetwork/ Diamondback_Moth.htm http://www.nysaes.cornell.edu/ent/dbm/ http://www.nre.vic.gov.au/agvic/ihd/projects/dbm.htm Forthcoming conference 4th International Workshop on the Management of Diamondback Moth and Other Crucifer Pests 26–29 November 2001 University of Melbourne Victoria Australia.For further details see http://www.conferences. unimelb.edu.au/moth/ For further information contact richard.vickers@brs.ento.csiro.au nancy.endersby@nre.vic.gov.au FEEDBACK Paterson’s curse The taxonomic name for Paterson’s curse mentioned in the April issue (Pesticide Outlook 2001 12(2) 49) should have been quoted as Echium plantagineum. Wherever known we publish Latin taxonomic names to help international readers in the identification of organisms. Paterson’s curse allegedly received its common name from the Paterson family who lived near Albury New South Wales who brought the seed from Europe so they could grow it in their garden. FRAC In our August 2001 issue (Pesticide Outlook 2001 12(4) 165) the organisation FRAC should have been identified as the Fungicide Resistance Action Committee and not as Fungicide Resistance Action Group.Monarch butterflies Since the publication of the article in Pesticide Outlook by James McLaren (Pesticide Outlook 2001 12(4) 136) on monarch butterflies a new study by Mark Sears of the Department of Environmental Biology at the University of Guelph in Canada was discussed at the ACS National Meeting at Chicago in August. Sears and his team looked at how far pollen travelled in a corn field if monarch butterflies were exposed to it and how much of it the larvae typically ate. The research funded by the Canadian government took place on corn fields in Canada Iowa Maryland and Minnesota between 1999 and 2000. They saw no adverse effects except when larvae ate about 4000 pollen grains.However because there is an average of only 120 pollen grains per cm2 of a milkweed leaf it was concluded that it is highly unlikely that larvae are going to be exposed to that much pollen to cause a measurable effect. BIOLOGICAL CONTROL Richard Vickers has been working with CSIRO on insect pests of horticulture for over 30 years. His major focus has been on the application of sex pheromones for controlling and/or monitoring pest populations and he was closely involved with the research that lead to the development of mating disruption systems for oriental fruit moth codling moth and a clearwing borer of persimmons. All three systems are now commercially available. His current involvement in developing autodissemination as a control technique adds an exciting new dimension to his pheromone research. Peter Ridland has been developing pest management strategies for a range of agricultural and horticultural crops in Victoria since 1994. Since 1993 he has worked with two horticultural industries with serious pest problems due to insecticide resistance namely diamondback moth in brassica crops and Helicoverpa armigera in sweet corn. He currently leads an ACIAR-funded project working on the leafminer Liriomyza huidobrensis in Indonesia. Nancy Endersby has worked on Integrated Pest Management in brassica crops for 12 years training crop scouts and monitoring diamondback moth populations for insecticide resistance. She is currently working on a CESAR PhD project on the molecular genetic structure of Australian populations of diamondback moth supervised by Steve McKechnie at Monash University. Pesticide Outlook – October 2001 187

ISSN:0956-1250    

DOI:10.1039/b108598k

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

SUGAR BEET CROP PROTECTION IN SUGAR BEET Mike May from IACR-Broom’s Barn in Suffolk UK discusses crop protection in sugar beet especially in the UK but also throughout Europe cereals (approximately 80% follows winter wheat). The ideal drilling dates are between 10 March and 10 April but this can be delayed by the weather. Drilling earlier than this will put the crop at risk of bolting (producing flowering stems instead of harvestable roots) as a result of vernalisation by periods of cold weather. Harvesting (Figure 1) starts as soon as the factories open (mid-late September) and on light soils may continue until the factories close (mid- February). On heavier soils harvesting is usually completed before Christmas. Beet awaiting delivery to the factory is stored (usually in outdoor clamps but sometimes in redundant buildings).Delivery is governed by a system of permits that are allocated by the sugar factory staff. Drilling dates in different countries are governed by the weather and there is both a spring and an autumn drilled crop in Spain. The autumn drilled area is in the south around Seville whilst spring drilling is carried out further north. The UK has one of the longest campaign lengths (opening of factories) at approximately 150 days–around 100 days is the norm in most other European countries. Introduction Sugar beet is an important crop in the UK. Not only is it relatively profitable for the farmer but it also provides an important spring sown break for many combinable crop rotations that are dominated by winter wheat.Just under 30% of the world’s sugar (sucrose) is produced from sugar beet and the rest from cane (Licht 1999). In Europe sugar beet is grown under a quota system governed by the EU. In 2001 sugar beet were grown on around 175,000 ha in the UK; this compares with 188,000 ha in 1998 (see Table 1 for European production). The main reasons for the reduction in area in the UK are increased yields through improved agronomy and varieties and favourable weather plus low prices for any surplus sugar that is produced in excess of the grower’s contracted quota. Sugar prices are set on an EU basis and UK growers have been disadvantaged owing to the high value of the £. In 2000 farmers received just over £27 t–1 of roots (adjusted to 16% sugar content) grown within their contract but approximately £6 t–1 for any surplus delivered to the factory (this comapres with over £37 t–1 and £11 t–1 respectively in 1996).Therefore there is no incentive for farmers to grow much more sugar beet than they require to meet or maintain their contracted tonnage. However the vagaries of the season especially drought means that most growers sow extra area (10–15%) to preserve their contract. Most sugar beet crops in the UK are preceded by winter Table 1. Top and bottom five European sugar beet producing countries (this data is from a variety of sources therefore discrepancies and variations may exist) France Germany Turkey Italy UK Greece Switzerland Ireland Finland Portugal Average area 1995–1998 (’000s ha) 425 530 400 275 175 45 25 25 35 2 Average raw sugar production (t ha–1) 10.9 8.2 5.0 6.1 8.6 Average sugar yield 1995–1998 1995–1998 (’000s t annum–1) 4630 4380 1970 1680 1500 320 220 200 160 10 Growing costs and changes in production The total cost of growing sugar beet in the UK is around £1100 ha–1 (Nix 2000).Crop protection is an essential element and cost around £25 million (approximately £150 7.2 8.8 8.4 4.9 5.7 Total Western Europe Total Eastern Europe 188 Pesticide Outlook – October 2001 This journal is © The Royal Society of Chemistry 2001 2600 6020 20790 9290 7.8 2.7 DOI 10.1039/b108605g Figure 1.A harvester demonstration – over half of the UK crop is harvested by contractors using six row machines such as this (Photograph British Sugar) ha–1) in 2000 (Source British Sugar Annual Crop Surveys). This was 7% less than in the previous season. Average spend per hectare on herbicides is usually between £105 and £120 ha–1 on insecticides approximately £40 ha–1 whilst around £15 ha–1 is spent on fungicides (but usually only half the crop area requires treatment against fungal leaf diseases). Average yields are usually around 55 t ha–1 of roots at 16% sugar. It is interesting to consider the UK Ministry of Agriculture Fisheries and Food (MAFF)1 statistics for the crop (Garthwaite and Thomas 1998) which show that over the 10 years to 1996 the area treated with pesticide increased 71% but the amount of active ingredient applied decreased by 35%.Between 1994 and 1996 the total area treated with herbicides increased 24% but the amount applied did not increase (608 tonnes in 1994; 604 tonnes in 1996). This is part of a general approach by growers who are willing to treat the crop more times if it means that the total amount of pesticide they use can be reduced. With weed control this is achieved by applying repeated low doses of herbicides to each weed flush when the weeds are small rather than Figure 2. Effect of weed on sugar beet yield. LEFT – clean plot in which a sequence of herbicide mixtures has been used to control weeds. RIGHT – Weedy plot in which yields have been severely reduced by lack of weed control.1 Now Department of Environment Food & Rural Affairs (DEFRA) Seed treatments and insecticides Most western European countries use pelleted seed to facilitate precision drilling but some such as Turkey still drill naked seed. Most growers aim for a final population of around 75,000 to 100,000 plants ha–1 and sow between 1.0 and 1.2 units of seed ha–1 (one unit = 100,000 seeds) in rows SUGAR BEET waiting and applying fewer but higher dose mixtures to slightly larger stage weeds. Before the 1970s multi-germ seed was used and this required hand thinning to take out the extra plants that were surplus to requirements. Up until this time most growers relied on hand labour and mechanical systems for weed control.Monogerm seed became available in the 1970s and at the same time herbicides such as phenmedipham chloridazon lenacil and ethofumesate were adopted resulting in less reliance on hand labour. Some countries such as Turkey still sow seed at close spacing and remove the surplus plants and control weeds with hand labour. Figure 3. Powdery mildew (Erysiphe betae) – the main postemergence disease that affects UK sugar beet crops Pesticide Outlook – October 2001 189 SUGAR BEET 45–70 cm apart. Seed is purchased in the UK with a standard dressing of thiram (10.5 g kg–1 of raw seed) and hymexazol (5.5 g kg–1 of raw seed) incorporated into the pellet. These fungicides are also used in many other European countries although doses vary according to disease risks.There is an option to purchase seed treated also with imidacloprid (at 90 g unit–1 of pelleted seed) or tefluthrin (10 g unit–1). In the UK approximately 4% of seeds are treated with tefluthrin for the control of soil pests (mainly millipedes such as Blaniulus spp. and Bracydesmesdus spp. springtails Onychiurus armatus and symphilids Scutigerella immaculata). Imidacloprid is used on around 75% of the UK area. Its use in western Europe is variable generally depending on the pest risks. For instance 90% of the Belgian and 70% of the French crop is treated whilst only 40% of the German crop is sown with imidacloprid. Carbamate granules are used on approximately 10% of the sugar beet area in the UK (the largest use is of aldicarb applied in the seed furrow at drilling to control free living nematodes (Docking disorder) Ditylenchus dipsaci and other soil pests.Some such as aldicarb are effective at controlling early attacks by aphids. Post-emergence insecticides are available but owing to the widescale use of imidacloprid or carbamate granules relatively few are used in most seasons. In countries where the use of imidacloprid seed treatment or carbamate granules is low use of postemergence insecticides is generally high. Approximately 60% of the imidacloprid use in the UK is for control of both soil and foliar pests the rest for control of mainly foliar pests especially aphids. Aphids seldom damage sugar beet directly but the green aphids Myzus persicae and Macrosiphum euphorbiae are vectors of virus yellows diseases which can reduce yields by up to 50% in the worst cases of early infection.Imidacloprid gives protection against early (up to 10–12 leaves stage) aphid attack. After the 12 leaves stage beet plants produce a substance that builds up in the gut of the aphid and essentially prevents it from eating so that it starves to death. Although aphid / virus forecasts are produced by IACRBroom’s Barn these are not available at the time growers order their seed (usually in July of the previous year). Therefore most growers prefer to adopt the insurance approach of ordering seed treated with imidacloprid to control soil pests and post-emergence pests such as aphids rather than wait and possibly use insecticide granules which need to be applied through special applicators on the drilling rig.Weed control The main weeds found in sugar beet in Europe include the perennial species Elymus repens and Cirsium arvense whilst common annual weeds include Chenopodium album Polygonum aviculare Matricaria chamomilla Fallopia convolvulus Sinapis arvensis and Stellaria media. Crop volunteers of potatoes and oilseed rape are present in many countries including the UK and weed beet (an annual form of Beta vulgaris) is a problem in many countries but particularly the UK where it is present in approximately 60% of sugar beet fields. 190 Pesticide Outlook – October 2001 The total potential losses from weeds would be between 50 and 100% of the potential crop yield (Figure 2).Sugar beet is not competitive with emerging weeds until it has at least 8 true leaves. Weed control in sugar beet relies on a sequence of herbicide applications. Over 50% of the UK crop is treated with glyphosate or paraquat +/– diquat prior to crop emergence. Much of the glyphosate is applied in the autumn or winter to control weeds present in the preceding stubble prior to ploughing with the rest applied to control weeds emerging after ploughing. Over 120 herbicide products (using 20 active ingredients – CABI 2001) are approved in the UK for weed control in sugar beet. However most of these herbicides are relatively ineffective compared to those used in other crops such as cereals and most will only control weeds at the small cotyledon to first true leaves stage.Therefore a sequence of herbicides is required to control the range of weeds that emerge in sequential flushes during the early spring after beet is sown. To help timing of post-emergence sprays approximately 44% of growers use a pre-emergence herbicide (the majority apply chloridazon). This usually replaces a post-emergence spray. Post-emergence weed control uses a sequence of two or more applications. The range of weed species controlled by each herbicide is also limited and so mixtures of herbicides are applied. Weedy fields such as those on peaty soils often require 6 to 8 postemergence sprays. Typically 4 to 5 applications of herbicide treatments are used each season.The most popular postemergence active ingredients (in order of use in 2000) are phenmedipham metamitron ethofumesate desmedipham triflusulfuron-methyl lenacil clopyralid and chloridazon. To improve herbicide activity mineral or vegetable oil-based adjuvants are added to over half the post-emergence treatments. Tractor hoeing between the rows is still employed on approximately 50% of the crop mainly to control weed beet. Similar systems of low dose postemergence weed control are used in most EU countries but there are numerous small variations. A high proportion of the Belgian crop is treated with pre-emergence residual herbicides; this is to provide flexibility in timing of postemergence treatments on their heavy soils whereas few of the Dutch or Swedish crops are treated with pre-emergence residual herbicides.France and the Netherlands tend to use less herbicide active ingredient per hectare than other countries but differences between countries are usually less than 10%. Post-emergence disease control In the UK post-emergence disease control is a feature from late July or early August when powdery mildew (Erysiphe betae) (Figure 3) starts to invade the crop. It usually starts in the South Eastern growing areas of Suffolk and appears later in Northern and Western beet areas. Average infestations for the last five years have been around 50% of the crop area. Forecasts based on winter and summer weather are provided for growers by IACR-Broom’s Barn. Until the advent of triazole fungicides in 1997 growers relied on sulfur for control of powdery mildew.In 2000 approximately 40% of the crop area was treated with triazole Potential changes that might result if herbicide tolerant beet introduced l More flexibility for growers in timing application of herbicides. l Herbicide costs reduced (by 70+%) but total cost will depend on technology fee. l Less need to control weeds in autumn stubbles. l Reduced weed control in other crops in the rotation? (Sugar beet is once again used as ‘cleaning crop’ for the rotation?) l Weed presence at early stage of crop might reduce risk of wind or water erosion of soil. Otherwise sow cover crop such as barley which will be easier to manage than with conventional herbicides. l Facilitate use of autumn sown cover crops (e.g.for nitrate leaching). l Weed presence later in season may reduce aphid attack. l Weed presence may increase populations of beneficial invertebrates. l Approximately 30% reduction in active ingredient use in UK (more in some countries less in others). l Control of weed (volunteer) beet – but will need management care to avoid herbicide tolerant volunteers. l Easier and cheaper control of perennial weeds particularly volunteer potatoes (can also reduce potato cyst nematode populations) and Cirsium arvense thistles. l High levels of weed control might reduce invertebrate populations and affect food chain for birds – this is being examined in DEFRA Farm Scale Evaluations. l Increase options for direct drilling or minimal tillage systems for sugar beet establishment.fungicides (cyproconazole or fluzilazole + carbendazim) mostly applied in tank mixture with sulfur. In other European countries Cercospera leaf spot (Cercospera beticola) is a common problem with control necessitating use of resistant cultivars and a sequence of fungicide sprays during the season. The future The UK sugar beet industry has been at the forefront of reducing inputs of both pesticides and fertilisers (nitrogen SUGAR BEET ON THE WEB http://www.sugarbeet.co.uk http://www.ib.be/cefs (European Committee of Sugar Producers) http://www.britishsugar.co.uk http://www.bbro.co.uk (British Beet Research Organisation) http://hometown.aol.com/asga/sugar.htm (American Sugarbeet Growers Association) http://www.iirb.org (International Institute for Beet Research) SUGAR BEET fertiliser applications have reduced from over 150 kg ha–1 in 1970 to the current level of just over 100 kg ha–1).Disease and pest forecasts have been developed and strategies implemented to improve weed control without increasing the amount of herbicide used or the use of tractor hoes. The main problem facing the sugar industry is to remain competitive when the returns from sugar continue to fall. Biotechnology could provide a solution to some of these problems and the first of such crops which have tolerance to glyphosate (see BOX) are included in the DEFRA Farm Scale Evaluations. These will be completed in 2003 and so it is unlikely that such crops could be grown commercially until 2005 at the earliest. Acknowledgements The author is grateful to British Sugar for the use of its Annual Crop Surveys. These surveys are the source of much of the data used in this paper. References CABI (2001) The UK Pesticide Guide 2001. CABI Publishing Wallingford UK. Garthwaite D. G. and Thomas M. R. (1998) MAFF Pesticide Usage Survey Report 159 Arable Farm Crops in Great Britain 1998. Ministry of Agriculture Fisheries and Food London. Licht F. O. (1999) World Sugar and Sweetener Yearbook 1999/2000. F. O. Licht GmbH Tunbridge Wells. 114 pp. Nix J. (2000) Farm Management Notebook 31st Edition Imperial College at Wye Ashford UK. 256 pp. Mike May is Senior Liaison Officer at IACR-Broom’s Barn (http://www.iacr.bbsrc.ac.uk/broom) responsible for sugar beet technology transfer to UK sugar beet growers and advisers for the research station and the British Beet Research Organisation. Pesticide Outlook – October 2001 191

ISSN:0956-1250    

DOI:10.1039/b108605g

出版商:RSC    

年代:2001

数据来源: RSC