A Cytogenetic Analysis of Sterility in Interspecific Hybrid <i>Solanum indicum</i> Linn.×<i>Solanum melongena</i> Linn

Abstract

An interspecific hybridisation between the two species S. indicum L. and S. melongena L. was attempted, and the occurrence of hybrid sterility was analysed based upon the cytological, morphological and genetical behaviour of F1, amphidiploid, F2 and back cross progenies. The hybrid sterility might be due to the nonsynchronisation of chromosomes at metaphase plate and controlled by genic factors. The non-reduction in chiasma frequency in the hybrid and the occurrence of free recombination in the hybrid derivatives precludes the possibilities of segmental difference between the parental chromosomes. The resulting amphidiploid of the hybrid (S. indicum L.×SM.34) did not restore fertility and this forms a very concrete proof in supporting the genic cause for the hybrid sterility. The occurrence of petaloid anthers in some of the male sterile segregants in the F2 and melongena backcross progenies also revealed that it was due to diplontic sterility. The fertility levels of F2 and back cross progenies ranged from 0-89 per cent with a continuous variation indicating the sterility must be governed by major genes withmo difiers involved. There are indications which revealed that the male and ovule sterility in this species cross must be governed by different independent non allelic genes or gene complexes.