Alternaria brassicae, A. brassicicola
Most crucifer plants are susceptible to Alternaria leaf spot and plants at all growth stages may be affected. Symptoms caused by the two pathogens are very similar and both may be found on the same plant. Infection of seedling stems may result in damping-off or stunted plants.
This publication is an extensive vegetable production guide that addresses topics such as marketing aspects for production decisions, general production considerations, insect management, weed management, and disease management. You will find specific information for the following crops:
Update on diamondback moth (Plutella xylostella) insecticide resistance and the vegetable brassica insecticide management strategy
Turnip Mosaic Virus (TuMV) infects most cruciferous plants, but is most damaging in Chinese cabbage, turnip, mustard, and radish. The most common symptom in these crops is a distinct mosaic of light and dark green colors in the leaves. Depending upon the virus strain and the crop species, necrotic streaks, flecks, or ringspots may also occur. Necrotic spots and ringspots are the primary symptom in common cabbage, but the severity of symptoms is cultivar dependent.
Organic farmers rely primarily on preventive, cultural, and integrated methods of pest and disease management. Additionally, there are a number of materials that can complement and support organic management. This guide was developed to provide a useful and scientifically accurate reference for organic farmers and agricultural professionals who are searching for information on best practices, available materials, and perhaps most importantly, the efficacy of materials that are allowed for use in organic systems.
Xanthomonas campestris pv. Armoraciae
Xanthomonas leaf spot occurs on all cultivated crucifers and several wild crucifers. The major symptom is leaf spotting, but lesions can also occur on cotyledons, flower stalks, and fruit. Small leaf spots occur scattered over the leaf surface as a result of invasion of bacterium through pores.
Xanthomonas campestris pv. campestris
Black rot occurs on all cultivated crucifers and several wild species. Lesions typically begin at the leaf margin and progress inward forming V-shaped chlorotic lesions. With time the lesions begin to dry and become necrotic. Infection normally occurs through leaf pores, but it can occur any place on the leaf where insect or mechanical wounds allow for bacterial entry.