Abstract :
Serological atid biological comparisons were tnade
atnottg 45 seed-borne isolates of blackeye cowpea mosaic
(BICMV) and 54 seed-borne isolates of cowpea aphidborne
mosaic (CAbMV) potyviruses derived from
cowpea seedlots or young nursery-grown seedlings comprising
2112 germplasm accessions or pre-introduction
seedlots of Vigna unguiculata. Isolates were identified by
DAS-ELISA tising polyclonal immtinoglobulin G specific
for these viruses. Twenty isolates of BICMV and 32
isolates of CAbMV were also compared by ACP-ELISA
with selected monoclonal antibodies and by SDS-immunodiffusion.
By all approaches, isolates of BICMV were
clearly distinguished frotn CAbMV isolates. Isolate comparisoits
on selected cowpea genotypes (TVu-401, TVu-
1582, TVu-2657, and TVu-3433) partitioned most isolates
into two distinct groups. A few isolates seed-borne
in Indian cv, Pusa Phalguni, however, were clearly
BICMV by all serological tests, but behaved as CAbMV
in definitive cowpea genotypes. Although BICMV is generally
considered to be a ʹnew world virusʹ, both BICMV
and CAbMV occurred in V. unguiculata seedlots originating
in ʹold-world regionsʹ, including Afghanistan,
Botswana, Nigeria, Senegal, and South Africa. Seedborne
CAbMV was isolated from 6 of 155 tested US V.
unguiculata Germplasm accessions originating, respectively,
in Afghanistan (2), Botswana (2), India (1), and
Pakistan (1).
