Introduction ush bean (Phaseolus vulgaris L.) is popularly cultivated in Chittagong, Sylhet, North Bengal, Hill tracts and also many other districts of Bangladesh. The average green pod yield of this crop in Bangladesh is 13-20 t ha-1 (Khalequzzaman and Hossain, 2008) and seed yield 1.5-3.0 t ha-1 (Anon. 2008). The average yield production of bush bean is very low in Bangladesh due to various reasons, where disease is considered as important one. A number of soil-borne plant pathogens such as F. oxysporum, R. solani and S. rolfsii can cause severe seedling mortality of bush bean (Siddique et al., 2014). Among the various diseases of bush bean at field soil, the dry root rot