THE OCCURRENCE OF BEAN COMMON MOSAIC NECROSIS VIRUS IN WILD AND FORAGE LEGUMES IN UGANDA

Bean common mosaic necrosis virus (BCMNV) was isolated from Centrosema pubescens, Crotalaria incana, Lablab purpureus, Phaseolus lunatus, Se nna bicapsularis, S. sophera, Vigna vexillata and an unidentified Crot alaria species growing in Uganda. Thirteen distinct isolates were char acterized using symptoms, pathogenicity in differential bean cultivars , serology, immunosorbent electron microscopy, and seed and aphid tran smission. Some isolates conformed with the characteristics of previous ly described strains of BCMNV but others showed novel properties. All isolates reinfected the natural host from which they were obtained. Th e origin and ecological significance of these isolates is discussed.