INTERSPECIFIC HYBRIDIZATION AND CROSSABILITY STUDIES AMONG CULTIVATED AND CLOSELY RELATED WILD Vigna SPECIES IN INDL\N GENE CENTRE

Abstract

Int~rspecificcrosses amongdifferent cultivatedand wild speciesofgenus
Vigna were attempted involving mung bean N. radiata (L) var. radiata
Wilczek), V. radiata (L) var. sublobata (Roxb.) Verde., urad bean N. mungo
(L) Hepper) andwildprogenitor V. mungo (L) var. silvestrisLukokiMarechal
and Otoul. The reciprocal crosses were simultaneously attempted in each
cases and vice-versa. Several other crosses between V. radiata var. subloba~
andV. trilobataAit.and also with rice bean N. umbellata(Thunb.)Ohwi anc;l
Ohashi were performed. Successful crosses were established between n.ul'lg
bean with its wild putative progenitor form V. radiata var. sublobata. Fertile
F1 hybrids were also successfully produced from crosses involving urad bean
with its closely allied species V. mungo var. silvestris. Interestingly, mung
bean when used as a female parent in the cross combinations involving var.
sublobata and var. siIvestris independently, exhibited considerable cross
compatibility. The results clearly suggest that above allied taxa fall into the
primarygenepoolsanddo notpossessgenetic barriers. V. umbellata exhibited
cross incompatibility barriers when crossed with V. radiata var. sublobata.
The reasons for failure of crosses have been critically analysed deriving
evidential support from several other investigations. The paper presents a
comprehensive review on the interspecific"hylwidization to identify closely
related genepools ofAsiatic species ofVigna based on crossability studies