INHERITANCE AND ALLELISM OF RESISTANCE TO A SEVERE STRAIN OF BEAN YELLOW MOSAIC-VIRUS IN COMMON BEAN

Reaction in common bean (Phaseolus vulgaris) to the severe necrotic strain of bean yellow mosaic virus (BYMV-S) in F1 hybrids and F2 progeny of crosses between the susceptible cultivar OAC Seaforth and the resistant cultivars GN1140, Imuna, and Amanda revealed that resistance in these cultivars was conditioned by a single recessive gene. F1 hybrids and F2 progeny of crosses between the resistant cultivar Harokent and the other resistant cultivars, and of crosses between GN1140 and Imuna or Amanda were all resistant to BYMV-S. These results indicated that resistance to BYMV-S in all the resistant cultivars was due to the cyv gene (previously known as by-3 gene), reported first in GN1140.