Pathogenic variability of Albugo candida isolates from Punjab causing white rust disease of mustard

Development of white rust is dependent upon factors like pathogenecity of the pathogen, amount of available initial inoculum, time of first appearance of the disease and prevailing weather conditions. Pathogenic variability of Albugo candida isolates collected from different mustard growing areas of Punjab was studied on different Brassica hosts. Eleven selected isolates were tested which showed variation on different parameters like incubation period, number and size of pustules, number and per cent germination of sporangia. Isolate Ac 32 of group AC III showed more virulence as compared to other isolates.