Prevalence of phytophthora blight of pigeonpea in the Deccan Plateau of India

Phytophthora blight (PB), caused by Phytophthora drechsleri f. sp. cajani is the third potentially important disease of pigeonpea in the Deccan Plateau (DP) of India after wilt and sterility mosaic. In the rainy-season of 2005, an outbreak of PB was seen throughout DP. To quantify the incidence and spread of the disease, a systematic survey was conducted in the major pigeonpea growing regions of DP during the crop season 2005. Attempts were made to determine the effect of cropping systems on the PB development and identify resistant cultivars, if any, grown by farmers and on research farms. Widespread incidence of PB was recorded on improved, and or local cultivars grown in different intercropping systems. Majority of improved cultivars grown at research farms were found susceptible to PB (>10% disease incidence). Pigeonpea intercropped with groundnut, black gram and coriander had less disease incidence (≤10%). Three wilt and SM resistant pigeonpea cultivars KPL 96053, ICPL 99044, and ICPL 93179 were found resistant (