A new seedborne strain of cucumber mosaic cucumovirus (CMV) that induc
es severe symptoms on many cowpea genotypes was detected in Georgia in
1994. This strain, designated CMV-Csb, is asymptomatic on tobacco, bu
t it produces more severe cowpea stunt symptoms when present in combin
ation with blackeye cowpea mosaic potyvirus than do the more prevalent
CMV isolates. The new strain is seedborne in cowpea (1.5 to 37%), has
no associated satellite RNA, and is classified as a member of subgrou
p I of CMV strains based on nucleic acid hybridization assays.