potato 5-9-12 CLEAN - Vegetableipmasia.org

ORGANIC POTATO PRODUCTION Scouting fields weekly is key to early detection andevaluation of control measures. The earlier a disease isdetected, the more likely it can be suppressed with organicfungicides. Accurate identification of disease problems,especially recognizing whether they are caused by abacterium or fungus, is essential for choosing an effectivecontrol strategy. Anticipate which diseases are likely to beproblems and be ready to take control action in a timelymanner. Allowing pest populations to build past thresholdscan leave few or no options for control. Thresholdspresented here were developed for use with conventionalfungicides, and may need to be adjusted downward whenusing materials approved for organic production, which tendto be less effective and have shorter residual activity.When available, scouting protocols can be found in thesections for each individual disease. While following asystematic scouting plan, keep watch for other diseaseproblems when walking a field.All currently available fungicides allowed for organicproduction are protectants meaning they must be present onthe plant surface before disease inoculum arrives toeffectively prevent infection. Biological products must behandled carefully to keep the microbes alive. In additionto disease control, fungicides containing copper may haveantifeedant activity against some insect pests including theColorado potato beetle. Follow label instructions carefullyto achieve the best results.Use weather-based disease forecasting programs whenavailable to help time applications to periods of favorableweather or the arrival of inoculum. The movement of somepathogens that do not overwinter in the Northeast may betracked online to help determine when control measures areneeded. Contact New York State IPM’s network for theenvironment and weather (Reference 4) for late blightforecasting in your area.Contact your local cooperative extension office to see ifnewsletters and pest management updates are available foryour region, for example, the Cornell Cooperative ExtensionRegional Vegetable Program in Western New York offerssubscriptions to Pestminder, a report that gives timelyinformation regarding crop development, pest activity andcontrol, and VegEdge, a monthly newsletter with articles onpest management. In the Albany area, information isavailable through the weekly Vegetable Pest Status Report.Organic farms must comply with all other regulationsregarding pesticide applications. See Section 11: UsingOrganic Pesticides for details. ALWAYS check with yourorganic farm certifier when planning pesticideapplications.Resources: Cornell Vegetable MD Online (Reference 57). Resource Guide for Organic Insect and Disease Management (Reference 2). 242012