Head cabbage clubing problem

A farmer had complained to us about root clubing problem on his young head cabbage plants in the field. It started in one section of the plot and is spreading to other parts. I suspect the problem to be due to nematode attack. Any information on the causal agent and its control measures will be much appreciated… Mark

RESPONSES:

From John: Club root of cabbage is caused by Plasmodiophorabrassicae a soil living fungus. Equipment used in intercultivation enables rapid spread of the disease. Raising the pH of the soil by liming will help. Soil drench with fungicide is useful to begin with. I have found good old bordeaux mixture useful. For long term management, avoid brassicas in that plot for a few rotations at least.

From Malvika: Club root is a disease caused by agetn called Plasmidophora brassicae which is a myxomycetes: it is generally spread due to contamination in irrigation water.

From John: From the photos, I am guessing that the cabbage seedling is 2-3 weeks old. If that is true, the root symptoms appear far too advanced to pin it on nematodes, although there are a few typical Meloidogyne nodules.  Another reason why nematode infestation is less likely, is because brassicas are generally less susceptible to nematodes than many other vegetable crops – to the extent that it is often used in a rotation after a Meloidogyne-susceptible crop. (I must hasten to add that this resistance is not guaranteed across sub species and varieties). This makes Plasmodiophora the most likely culprit.