Callus induction was tried with leaf explants (third leaf from top of canopy) harvested from in situ control and supplementary UV-B irradiated (UV-B = 2 hours daily @ 12.2 kJ m-2 d -1 ; ambient = 10 kJ m-2 d -1 ) GOWMATHI, FOLA and NS-634 varieties of cowpea to study their efficiency for germplam conservation. Callus induction occurred both in control and UV-B stressed GOWMATHI leaf explants. Both control and UV-B stressed FOLA leaf explants failed to initiate callus. Induction of callus occurred in UV-B stressed NS-634 leaf explants alone, while no callus was formed by the control. As only the leaf explants from GOWMATHI and NS-634 varieties of cowpea responded to in vitro callus proliferation, they are the best suited for germplasm conservation for cultivating in UV-B elevated habitat.
