Morphological and physiological variability in Bipolaris sorokiniana

Variability among 6 isolates of Bipolaris sorokiniana (Sacc. in Sorokin) Shoem. was studied in respect of morphological and physiological variability. The isolates BS-F-5 and BS-P-3 were found to be fast growing and high sporulating. The isolates BS-DWR-K-1, BS-K-4, and BS-V-6 were found to be medium in growth and sporulation, whereas BS-D-2 was slow growing and least sporulating. Among the phosphorus sources, dipotassium hydrogen orthophosphate was best for growth and sporulation, whereas sodium phosphate was inhibitory for growth and sporulation of all isolates. Among the potassium sources, potassium nitrate was best and potassium sulphate was inhibitory for growth and sporulation of all isolates. Among the vitamins, thiamine supported maximum growth of all isolates, whereas yeast extract supported maximum sporulation. Inositol and calcium pentothenate were found to be inhibitory for growth of all isolates.