Status of yellow mosaic virus and whitefly Bemisia Tabaci biotypes on mungbean in southern Karnataka

Mungbean Yellow Mosaic Virus (MYMV) is a serious pathogen on mungbean in southern Karnataka where the crop is grown during early kharif by making use of pre monsoon showers. Survey of major mungbean growing areas of Southern Karnataka indicated the occurrence of disease ranging from 31.49 to 100 per cent. The highest average incidence (79.54%) was recorded in Tumkur district followed by Chickmagalur (59.73%), Hassan (56.57%), Shimoga (56.71%), Mysore (51.88%), Davanagere (51.09%), Chitradurga (48.11%) and Mandya district (45.58%). The RAPD analysis of whitefly samples collected in the surveyed areas has indicated the occurrence of B biotype Bemisia tabaci. The occurrence of B biotype of B. tabaci and large scale cultivation of susceptible varieties are implicated as the reasons for increased incidence of MYMV in these areas.