Distribution, Diversity and Species Relationships of Wild Vigna species in Mungo-Radiata Complex

Abstract

A total of 107 populations of 5 Vigna species in the mungo-radiata complex from different phytogeographical
regions of India were collected. These species occurred in different associations as components of the herbaceous
and grassy undergrowth or are seen twining on bushes in scrub vegetation. V. mungo var. silvestris was widespread
in northern parts of the Western Ghats. Sporadic occurrence of this species was recorded from parts of Rajasthan,
Madhya Pradesh and Maharashtra. V. radiata var. sublobata was widespread in the Western Ghats. Sporadic
distribution of this species was recorded from the north-western Himalayas, parts of Rajasthan, Madhya Pradesh,
Maharashtra, and southern parts of the Western Ghats. V. radiata var. setulosa populations were ofsporadic occurrence
in northern parts of the Western Ghats and north-eastern region of the Eastern Ghats. V. hainiana populations were
widespread in central plateau region and parts of the Eastern Ghats. Sporadic distribution of this species was also
recorded from north-western Himalayas. V. khandaklensis, was endemic to northern parts of Western Ghats. Diversity
of the collected germplasm for various morphological characters was assessed. Data on 45 selected qualitative and
quantitative traits were subjected to multivariate analysis for establishing species relationships and assessing the
pattern of inter- and intra-specific variation. Except for V. khandalensis, all other species, V. radiata var. sublobata,
V. radiata var. setulosa, V. mungo var. silvestris and V. hainiana showed greater homology in growth habit. The
species, however, differed in other plant, flower, pod and seed characteristics. V. khandalensis was distinct from
all other species in an erect growth habit, large foliaceous stipules and broad leaves. Within species variations were
more in V. mungo var. silvestris populations. The cultigen types of V. mungo and V. radiata showed greater homology
to the conspecific wild species in morphological characteristics, the former were however more robust in growth.
with large vegetative parts, erect growth and three to fivefold increase in seed size and seed weight. Wild species
have a great potential as sources of disease resistance and other useful traits. Intensive collection, characterisation
and conservation of the species diversity and intraspecific variation. particularly of the conspecific wild relatives
with valuable characters, therefore assumes great priority to make extended cultivation economically attractive.