Interspecific Hybridization of Vigna radiata x
13 wild Vigna species
Pandiyan M. , N. Senthil, N. Ramamoorthi and T. Jayaraj
National Pulses Research Centre, Vamban Colony ,Tamil Nadu Agricultural University
Pudukkottai, District

Abstract
With an objective to develop superior segregants for yield components coupled with pest and disease resistance interspecific crosses were attempted with thirteen wild relatives of mungbean (V. radiata )viz., V. radiata var. sublobata , V. mungo var. silvestris , V. hainiana , V. umbellata , V. vexillata , V. trilobata ,V. glabrescens , V. pilosa , V. aconitifolia , V. stipulacea . V. bourneae , V. khandalensis and V. dalzelliana . For
reciprocal cross combinations the following species viz., V. radiata var. sublobata , V. mungo var. silvestris , V.

hainiana , V. umbellata , V. vexillata , V. trilobata were employed with V. radiata as male parent.
The highest pod set of 25 and crossability of 22% was recorded for the cross V. radiata x V. radiatavar. sublobata and lowest pod set of 2% recorded by the cross V. radiata x V. dalzelliana in the direct crosscombinations. The cross V. hainiana x V. radiata recorded highest crossing percentage of 11%. The cross V.

radiata var. sublobata x V. radiata recorded highest pod set of 15 and 6.6% while V. vexillata x V. radiata
possessed low crossability of 2.8%. Among the crosses made V. radiata x V. hainiana recorded the highest
hybrid germination 80% and lowest germination per cent of 13.3% was recorded by the V. umbellata x V.

radiata . Even though crossability barriers were predominant, it was possible to recover interspecific hybridsfrom all the thirteen direct and six reciprocal crosses. Hybrid break down was high in the cross combination of 43.8% where as Vigna hainiana x V. radiata recorded 100% low and inviable hybrids were also
observed in the F1 hybrids. Higher percentage of hybrid leathality was recorded in two crosses namely V.

radiata x V. mungo var. silvestris and Vigna radiata x V. khandalensis in direct crosses combinations.
The highest pollen germination 69.7% was recorded from the cross V. radiata x V. radiata var. sublo-bata . The estimates of pollen fertility were sufficient to recover F2 segregants in all the cross combinations.
For quantitative traits the interspecific cross V. umbellata x V. radiata exhibited high per se performance for two traits - number of branches per plant and hundred seed weight. For seed yield the hybrid of
the cross V. radiata x V. trilobata registered the highest mean value among direct crosses. In the F2 generation, for all the traits in the majority of the crosses the skewness was positive indicating the predominanceof dominant alleles. Among the direct crosses V. radiata x V. mungo var. silvestris exhibited highest value
for four characters - number of clusters per branch, number of clusters per plant, number of pods per plantand single plant yield. The cross V. umbellata x V. radiata showed better performance for the characters number of branches and number of clusters in the reciprocal direction, The cross V. trilobata x V. radiata
recorded best performance for two characters - number of clusters per plant and number of pods per plant.

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