Categorization vt Alternaria brassicae isolates on the basis of differential sensitivity to fungicides

摘要

Differential sensitivity of Alternaria brassicae isolates collected from different locations of India was tested by spore germination inhibition method to various commonly used fungicides. The results revealed that Emisan-6 was highly effective against all the isolates in inhibiting the spore germination, followed by Ridomil MZ-72. Variations were also observed among the isolates in their sensitivity against these fungicides. Data revealed that isolates RC-781, KGR, Varuna, PNT and CAUL were highly sensitive to Emisan-6 and two isolates Balba and GRN were also highly sensitive to Ridomil MZ-72 as less than ten per cent spores germinated. Similarly, isolate Balba in addition to Emisan-6 and Ridomil MZ-72, was also sensitive to Sulfex, Captan, Bavistin, and Vitavax whereas isolate BHP was sensitive to Dithane M-45, Captan, Kitazin, Vitavax and Raxil. All the isolates according to their sensitivity against different fungicides could be categorized into six groups and these groups can be designated aspathotypes/ races present in Indian conditions infecting rapeseed and mustard.