Variability among isolates of Sclerotium rolfsii Sacc. causing collar rot of chickpea

Chickpea (Cicer arietinum L.) is the one of the most important post rainy season pulse crops cultivated in Madhya Pradesh. It is threatening the chickpea crop grown in rotation with soybean or paddy. Incidence of collar rot in 15 to 45 days old crop ranged from 5–30% in 51 locations surveyed nearby Jabalpur. Investigations on variations in 51 isolates of Sclerotium rolfsii showed considerable variation with regards to cultural and morphological characters on PDA medium. These isolates may be broadly grouped into three pathotypes. The pathogenicity test showed the isolates to vary in number of days taken to initiate plant mortality and 100% mortality.