Inheritance of resistance to the NL-8 strain of bean common mosaic necrosis virus in bean

Bean common mosaic necrosis virus (BCMNV) includes four African strains, BC MNV-NL3, -NL-5, -NL8, and -TN1, previously considered to be members of the bean common mosaic virus (BCMV) group. Many bean cultivars resistant to BCM NV-NL8 were found to be susceptible to the other strains of the virus. 'Cal ifornia Light Red Kidney' (CLRK) and 'Carbon', resistant to BCMNV-NL8, were crossed with the susceptible cultivars Sanilac or Black Turtle 2 (BT-2). I n plants of F-1, F-2, and reciprocal backcross populations involving CLRK x 'Sanilac' or BT-2 x 'Carbon', the resistance to BCMVN-NL8 was determined t o be conferred by a single dominant factor. The same factor was detected in BCMNV-NL8-resistant 'Great Northern 1140' and 'IVT-7214, when crossed with the susceptible cultivar Stringless Refugee or BT-2.