potato 5-9-12 CLEAN - Vegetableipmasia.org

ORGANIC POTATO PRODUCTION Table 12.1.1 Pesticides Labeled for Organic Potato Disease Management. BACTERIAL SOFT ROT, Erwinia spp. FUSARIUM DRY ROT Fusarium spp.EARLY BLGHT Alternaria solani LATE BLIGHT Phytoph-­thora infestans CLASS OF COMPOUNDS Product Name (active ingredient) (copper octanoate) Nordox 75 WG (cuprous oxide) b b NuCop 50DF (copper hydroxide) c c Nu-­‐Cop 50 WP (cupric hydroxide) c c *Quimag Quimicos Aguila Copper c VERTICIUM WILT FUSARIUM WILT CANKER AND BLACK SCURF Rhizoctonia solani BOTRYTIS VINE ROT Sulfate Crystal (copper sulfate) OTHER Milstop (potassium bicarbonate) c c Organic JMS Stylet Oil (paraffinic oil) c c StorOx 2.0 (hydrogen d d d d d peroxide/peroxyacetic acid) PERpose Plus (hydrogen c c c c c c c c c c c c c peroxide/dioxide) OxiDate (hydrogen peroxide) a c c * Restricted use pesticide. Restricted-­‐use pesticides can be purchased only by certified applicators and used by certified applicators or by those under the direct supervision of a certified applicator. a = seed treatment, b = in furrow/ soil drench, c = foliar treatment, d= post harvest treatment, e = fixed copper fungicides include basic/tribasic copper sulfate, copper oxychloride sulfate, as well as copper hydroxide. Copper will build up in the soil, depending on a variety of factors. In general, copper hydroxides are less toxic than copper sulfates. See HUcopper products fact sheetUH (Reference 2) for more information about using copper. 1. For post harvest control of silver scurf on a UfoodU potato crop, clove oil must be certified organic. For post harvest silver scurf control for UseedU potato crop, clove oil must be 100% pure, but not necessarily certified organic. (Reference 44) See 12.16: Silver scurf. a, b, c or d = labeled for pest in New York and OMRI listed 12.1 Bacterial Soft Rot, Erwinia spp.Time for concern: At planting, and between harvesting and marketing. Wet, anaerobic soils favor the disease.Key characteristics: This bacterial pathogen can cause soft rot of infected tubers, resulting in seed piece decay and reducedyield and quality at harvest. Erwinia infection can also produce symptoms known as ‘black leg’: stunted, yellow stems thatbecome black and rotted at ground level. Tubers are infected through wounds or lenticels, and develop tan or water-soakedareas on the tuber surface. Advanced infections will be seen as soft rot of the tuber flesh. The amount of damage depends onthe population of the bacteria on and in the seed, seed storage and handling practices, and variety susceptibility. See CornellHUfact sheetUH (Reference 55) and Ohio State HUfact sheetUH (Reference 56) for photos and more information.Injury to potato plants by the European corn borer can cause sites for above and below ground Erwinia infection.Relative risk: Reduce risk to this wound pathogen by avoiding injuries and providing conditions favorable to wound healingat planting and harvest. See Sections 7.2: Seed preparation and handling, 7.3: Planting and 10.4: Curing and storage.WHITE MOLD COMMON SCAB PINK ROT POWDERY SCAB PYTHIUM LEAK SILVER SCURF i VIRUSES Management Option Scouting/thresholds, Crop rotation Site selection Resistant varieties Seed selection/treatment Planting Recommendation for Bacterial Soft Rot These are not currently viable management options. Choose well-­‐drained soils; wet, anaerobic conditions favor disease development. Infection of the lenticels is common in saturated soils. No resistant varieties are available. Plant varieties less susceptible to European corn borer. The primary source of inoculum is infected seedpieces. Plant only phytosanitary certified seed (See Section 7.1: Seed sources). Some growers have reduced seed piece decay by applying untreated fir bark to suberized seed pieces. The bacteria can spread to healthy seedpieces during cutting and planting. Clean and sanitize cutting equipment before use, during the cutting process and between seed lots. 262012