Blight-MOP

Development of a systems approachfor the management of late blight inEU organic potato productionPotato is a major cash crop in many European organic farming businesses.Compared to conventional production yields organic production yields are estima-ted to be between 30-40 % lower, even when copper is used to delay blightdevelopment in crops. Copper fungicides are estimated to extend the growingperiod by between 2-4 weeks. This is estimated to result in between 10 and 40% higher yields compared to crops not protected with copper. Yield reductionsgreater than 10-20 % resulting from the prohibition of copper fungicides couldthreaten the profitability of organic potato production and/or the entire organicfarming businesses in many EU-countries.

The quantitative target for the Blight-MOP project is to maintain potato yields andquality at levels currently obtained with the use of copper fungicides. An impor-tant aspect of the project will be rapid dissemination of results and adaptation ofstrategies to local potato management systems.

Late blight (caused by Phytophthora infestans) is the most devastating disease affecting organic (and conventional) potato production in the EU.

Under suitable environmental conditions(Temperatures between 15-23ºC; highhumidity/leaf wetness) the disease can spreadvery rapidly (Time between infection andsporulation 3-4 days) and can cause completecrop losses. Under blight conditions the use offungicides or tolerant varieties can only delaysymptom development/restrict the spread ofdisease.The recent emergence of sexual repro-duction of Phytophthora in Europe is expected topose additional problems for currently usedblight management systems.

The use of copper fungicides

Protective copper fungicides, which are currentlyused to control the disease in most organicproduction systems, are estimated to extend thelength of the growing season (the time periodbefore foliage is killed to avoid tuber infectionfrom infected leaves) by between 10 and 30days. However, copper fungicides will be bannedfor the use in organic farming from the year2002 (EU Regulation No 2092/91).

This level of income loss is expected to threatenthe economic viability of organic potato produc-tion and/or whole organic farming businesses(especially those which rely heavily on the incomefrom potato crops) in many areas of the EU.Since EU policies aimed at supporting anexpansion of organic production in the EU, areplacement for copper containing and otherchemical fungicides is urgently required.

To achieve this overall aim the following indivi-dual project objectives will be fulfilled:

1. Assessment of socio-economic impact of lateblight and ‘state of the art’ blight managementpractices in EU organic potato productionsystemsThe effect of EU Regulation No 2092/91banning the use of copper fungicides inorganic potato production is difficult toassess, due to a lack of reliable data.

This project will accordingly produce adetailed survey of the currently used blightmanagement systems of organic potatoproduction and the agronomic and economicimpact of the disease on organic potatoproduction in different regions of the EU.

2. Assessment of varietal performance in organicproduction systems in different EU regions andinteractions with local blight populationsPotato varieties with race specific and racenon specific resistance are available. However,their suitability as part of a blight manage-ment strategy has mainly been evaluated inconventional production systems. Such resultsmay be misleading because overall resistancemay be influenced by the production system.

The expected achievement will be a detailedfield characterisation of the: (i) agronomic andeconomic suitability of a range of varieties fororganic potato production in different areas ofthe EU; (ii) race structure and aggressivenessof local P. infestans populations and (iii)potential suitability of varieties for "in fielddiversification" strategies.

Late blight – a very devastating disease

3. Development of within field diversificationstrategies to prevent/delay blight epidemicsThere is some evidence that blight epidemicscan be prevented or at least delayed bygrowing potato varieties with different formsof resistance as mixtures or in alternatingrows.Another approach is to grow potato inalternating rows with other crops that canprovide physical barriers for spore dispersal.We will quantify the effect of these threedifferent diversification strategies on lateblight incidence and crop quality and yield.

The expected achievement will be anagronomic and economic evaluation of thethree different diversification strategies.

4. Optimisation of agronomic strategies for themanagement of late blightIn addition to the use of resistant/tolerantvarieties, ranges of other agronomic strategieshave been shown to reduce the incidence orat least the severities of late blight develop-ment.

The expected achievement will be blueprintsfor "locally adopted" agronomic managementsystems for late blight in EU-organic potatoproduction.

5. Development of alternative control treatmentsto copper fungicides, which comply withorganic farming standardsVarious alternative treatments have beendeveloped for the control of fungalpathogens. However, there are few reports ofsuccessful alternative control approachesusing these treatments against late blight andfew methods have been evaluated in fieldtrials.

The expected achievement will be theevaluation and possible further development,field evaluation and a cost/benefit analysis ofalternative blight control methods in organicproduction systems.This will facilitatecommercial exploitation after completion ofthe project.

6. Evaluation of novel application andformulation strategies for copper-free/alternative and copper based late blighttreatmentsAir assisted and electrostatic sprayer systemshave enabled a more complete and more uni-form spread of the effective principle on lea-ves and a substantial reduction in applicationrates for pesticides in conventional agricultu-re.We will evaluate such systems for the appli-cation of any alternative treatment(s) that maybe developed.

The expected achievements of this study willbe to (i) reduce the cost of biological treat-ments and (ii) provide blueprints for reducedcopper fungicide usage in case the regulatoryauthorities for organic potato productionagree a transitional period, during whichnovel compounds are developed and registe-red as commercial products.

7. Integration of optimised resistancemanagement, diversification, agronomic andtreatment strategies into existing organic potatomanagement systemsThe effect of integrating components ofmanagement practices and/or novel treat-ments developed under objective 2-6 will betested in replicated field trials.

The expected achievement will be improvedblight management systems, which are cust-omised/adapted to organic production sys-tems in different regions of the EU.

Blight-MOP is a EU funded research project.It was commenced on January 2001 and will lastfor 54 months

List of Participants

1. University of Newcastle (UNEW), England2. Research Institute of Organic Agriculture

(FiBL), Switzerland3. Institut National de la Recherche

Agronomique (INRA), France4 University of Kassel (KU), Germany5. Elm Farm Research Centre (EFRC), England6. Danish Institute of Agricultural Sciences

(DIAS), Denmark7. Federal Biological Research Centre (BBA),

Germany8. Swiss Federal Research Station of

Agroecology and Agriculture (FAL),CH9. Norwegian Centre for Ecological

Agriculture (NCEA), Norway10. Louis Bolk Instituut (LBI), Nederland11. Groupe de recherche en agriculture

Biologique (GRAB), France12. Dutch Research Institute for Plant

Protection (IPO-DLO), Nederland13. Agricultural Economics Research Institute

(LEI-DLO), Nederland

Project coordinatorCarlo Leifert, University of Newcastle (UNEW),England.

How to follow the projectThe primary website for the Blight-MOP projectis at http://www.ncl.ac.uk/tcoa/producers/research/blightmop

All Blight-MOP publications will be uploaded onthe website.

Upon completion of the project, an internationalworkshop (Potato blight control in organic potato production) will be organized atNewcastle University. This workshop will beused to present the results of the programme inthe context of related research carried out inother European Institutions.

A Technology implementation plan will be partof the final report submitted to the EU. Contractresearch organisations, which also provide agro-nomic advice and consultancy services to theorganic industry (NCL/SAC, FiBL, KU, EFRC, DIAS,NCEA, LBI, GRAB), will set up annual workshops.

Facts on Blight-MOP

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