potato 5-9-12 CLEAN - Vegetableipmasia.org

ORGANIC POTATO PRODUCTION Management Option management Compound (s) Recommendation for Common Scab conventional potato production do not seem to apply in organic production, perhaps due to the differences in microbial communities and the way organically and conventionally managed soils assimilate new additions of organic matter. Manure from cows fed infected tubers can spread the disease because common scab bacteria can survive an animal’s digestive track. No compounds are available to manage Potato scab. At the time this guide was produced, the following materials were labeled in New York State for managing this pest and were allowable for organic production. Listing a pest on a pesticide label does not assure the pesticide’s effectiveness. The registration status of pesticides can and does change. Pesticides must be currently registered with the New York State Department of Environmental Conservation (DEC) to be used legally in NY. Those pesticides meeting requirements in EPA Ruling 40 CFR Part 152.25(b) (also known as 25(b) pesticides) do not require registration. Current NY pesticide registrations can be checked on the Pesticide Product, Ingredient, and Manufacturer System (PIMS website) http://pims.psur.cornell.edu/ (Reference 3). ALWAYS CHECK WITH YOUR CERTIFIER before using a new product. Table 12.11 Pesticides Labeled for Management of Common ScabClass of Compounds Product Name (active ingredient) BIOLOGICALS Serenade Soil (Bacillus subtilis str.n QST 713) OTHER PERpose Plus (hydrogen peroxide/dioxide) Trilogy (hydrophobic extract of neem oil) Product Rate PHI (days) REI (hours) Efficacy Comments 2 – 6 qts/A 0 4 ? Soil surface drench. Provides suppression only. 1 fl oz/Gal (initial/curative) 0.25-­‐0.33 fl oz/gal (weekly/preventative) 0.5-­‐1% in 25-­‐100 gal of water/A -­‐ 1 (interior); until dry (field) ? For initial or curative use, apply higher rate for 1 to 3 consecutive days. Then follow with weekly/preventative treatment. For weekly or preventative treatments, apply lower rate every five to seven days. At first signs of disease, use curative rate then resume weekly preventative treatment. -­‐ 4 ? Limited to a maximum of 2 lbs/acre/application. PHI = pre-­‐harvest interval, REI = restricted entry interval. -­‐ = pre-­‐harvest interval isn't specified on label. Efficacy: 1-­‐ effective in half or more of recent university trials, 2-­‐ effective in less than half of recent university trials, 3-­‐not effective in any known trials, ?-­‐ not reviewed or no research available 12.12 Bacterial Ring Rot, Clavibacter michiganensis subsp. sepedonicusTime for concern: Seed purchase, planting, throughout season, and at harvest.Key characteristics: When infected tubers are cut crosswise, a creamy yellow to brown breakdown of the vascular ring isobserved. In severe infections, squeezing the infected tuber causes a cream-colored, cheesy exudate to ooze from the vascularring. Secondary organisms attack infected tubers in storage and may cause skin cracks and a reddish brown discoloration.Symptoms are not always dramatic but laboratory tests should be done if presence of this bacterium is suspected. See CornellHUfact sheetUH (Reference 55) and Ohio State HUfact sheetUH (Reference 75) for photos and more information.Relative risk: Rarely seen in New York; serious damage when present because it can spread rapidly and cause significantlosses. There is zero tolerance for this bacterium in seed potatoes. Environmental conditions are not as important in diseasedevelopment as clean seed and good sanitation practices.Management Option Scouting/thresholds Resistant varieties Seed selection/treatment Recommendation for Bacterial Ring Rot Record the occurrence and severity of bacterial ring rot. No thresholds have been established for organic production. No resistant varieties are available. This is a seed borne disease, therefore using phytosanitary certified seed is key to preventing outbreaks (see Section 7.1: Seed sources). Serious crop losses can result if infected seed is used because the pathogen is readily spread during seed cutting and planting operations. 452012