potato 5-9-12 CLEAN - Vegetableipmasia.org

ORGANIC POTATO PRODUCTION Management Option Scouting/thresholds Site selection Resistant varieties Crop rotation Seed selection/treatment Harvest Postharvest Recommendation for Pythium Leak If fields have been flooded, scout for infection. Thresholds have not been established for organic production Select fields with low levels of this pathogen, as determined by pre-­‐plant soil sampling. Snowden and Marcy show some tolerance. Rotate out of potatoes at least 4 years. Plant phytosanitary certified seed. See 7.1: Seed sources. Avoid harvesting immature tubers during hot or wet weather. Avoid wounding tubers during harvest since this is the only means of entry for this Oomycete. Keep storage temperature low (40° to 45°F) if the disease is detected. 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 12.15 Pesticides Labeled for Management of Pythium Leak Class of Compounds Product Name (active ingredient) Product Rate PHI (days) BIOLOGICALS ActinoGrow (Streptomyces lydicus WYEC 108) Actino-­‐Iron (Streptomyces lydicus WYEC 108) Actinovate AG (Streptomyces lydicus WYEC 108) RootShield WP (Trichoderma harxianum 22 (KRL-­‐AG2)) Serenade Soil (Bacillus subtilis str. QST 713) SoilGard (Gliocladium virens str.GL-­‐21) T-­‐22 HC (Trichoderma harzianum) OTHER PERpose Plus (hydrogen peroxide/dioxide) str. T-­‐1-­‐12oz/A drench 2-­‐18oz/100lb seed* REI (hours) Efficacy Comments 0 1 or when sprays have dried ? *can be applied to seed in a slurry or dry in planter box. 10-­‐15 lb/A (in-­‐furrow) -­‐ 4 ? Water in after application 3-­‐12 oz/A foliar or drench 2-­‐18 oz/cwt seed pieces 0.3-­‐3oz/cwt seed 16 – 32 oz 0 1 ? Label recommends using a spreader sticker for foliar applications. REI is 0 for soil incorporated applications -­‐ Until sprays have dried Seed treatment may be applied dry or in a slurry. ? For use in planter box only. In-­‐furrow spray . 2-­‐6 qts/A 0 4 ? Used as a soil drench or in furrow application. 2 – 10 lbs 0 Until sprays have dried ? Apply in 50 – 100 gallons of water as a band drench in-­‐furrow. 0.5-­‐2.0 oz/cwt seed 0 0 ? Apply to seed pieces so surfaces are thoroughly covered with dust or aqueous suspension. 1 fl oz/Gal (initial/curative) 0.25-­‐0.33 fl oz/gal (weekly/preventative) -­‐ 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. 59B PHI = pre-­‐harvest interval, REI = restrictedentry 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 492012