White rust of crucifers : An overview of research progress

Abstract

The name rapeseed in Canada means both
Brassica napus and B. Campestris or B. rapa.
B. napus is completely resistant to white rust,
whereas all B. rapa varieties are very susceptible. Upto late 1970’s, white rust used to cause about 15 per cent yield losses in Canada. Albugo candida (Pers. Ex. Lev.) Kuntze. (A. cruciferarum S.F. Gray), the causal fungus of the white rust disease of many cruciferous crops, causes both local and general infection. Local infections produce white to cream coloured pustules on the undersides of leaves and on stems or pods, while general or flower bud infections cause extensive distortion, hypertrophy, hyperplasia and sterility of inflorescences (staghead). The staghead phase accounts for most of the yield loss attributed to this disease.