PEST MANAGEMENT DECISION GUIDE: GREEN AND YELLOW LIST Black rot disease of Xanthomonas campestris pv campestris Kuola kwa kabichi Prevention Monitoring Direct Control Direct Control Restrictions

l Use certified seed and seedlings free l Additional relevant crops: cauliflower, l Destroy crop l Use personal protective equipment when handling from disease as this disease can be seed- , brussel sprouts, residue by drying and applying pesticides, follow the label borne , mustard, , rape, radish and burning recommendations. l Use resistant varieties such as Marcanta l Monitor plants weekly for symptoms l Seeds of cabbage, where available from planting broccoli and l Do not eat, drink, smoke when mixing or applying pesticides. l Correct plant spacing: 50 cm between l Look for yellow V-shaped lesions with brussels sprouts Whole plant showing typical should be hot plants and 60 cm between rows an open part of 'V' along the edge of l Copper-based pesticides can be used to reduce the symptoms (CABI) water treated at the leaf o o spread of the disease: l Do not plant crucifers in areas that have a 122 F (50 C) for history of the disease l The diseased leaf area become 25 minutes l Apply copper hydroxide l WHO Class II - l Rotate crucifers 3-4 years with crops that brown and brittle l Seeds of (500 g/kg) (Funguran-OH Moderately hazardous. are not susceptible such as maize, l Affected leaf veins turn dark brown to Cauliflower, WP, Cungfu 583 SC) at a Apply at sight of legumes, tomato black and Turnip should rate of 150 ml/100 L. disease and every 7-14 l Avoid flood/furrow irrigation because it will l The V-shaped lesions enlarge and be hot water Multi-site contact activity. days. PHI 7 days. carry the disease from infected to the entire leaf evantually turns yellow treated at 122oF FRAC group M1 Ensure full coverage of uninfected areas or wilts and falls from the plant (50oC) for 15 the plant. Characteristic V shaped lesions l Avoid moving through fields when the l Infected seedlings remain stunted minutes spreading from the edge of plant are wet to prevent disease spread. and become unproductive l Apply copper oxychloride l WHO Class II - leaves and black veins (CABI) Clean tools and boots. (850 g/kg) (Copper Moderately hazardous. l There is a ring of black discoloured oxychloride 500 WP, Apply at sight of l Destroy alternative host weeds in the tissue within the stem when cut Suncop WP) at a rate of disease and every 7-14 crucifer family e.g. birdsrape mustard, l If 6-8 plants/ha show symptoms take 250 g/ha or 300 g/100L. days. PHI 7 days. Indian mustard, black mustard action Multi-site contact activity. Ensure full coverage of FRAC group M1 the plant.

Rot on cabbage stem (CABI)

Malawi CREATED/UPDATED: June 2016 AUTHOR(S): Elisa D.L. Mazuma (Department of Agricultural Research Services Chitedze Research Station) and Yakosa Tegha (Department of Agricultural Extension Services) EDITED BY: Plantwise

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