HETEROSIS, COMBINING ABILITY AND GENETIC DIVERGENCE IN COW PEA (VIGNA UNGUICULATA (L.) WALP.)

Abstract

Manifestation of heterosis for green pod yield and its components viz. plant height, number of branches per plant, pod length, pod weight, number of pods per cluster and per plant, number of seeds per pod and green pod yield per plant were examined in relation to genetic divergence of the parents and specific combining ability of the crosses in a Line x Tester design in vegetable cowpea. ICP-42 × Pusa Komal and ICP-54 × Pusa Komal were found heterotic due to of highly divergent parents. Heterosis did not always occur in crosses between widely divergent parents, but also observed in closely related parents such as in ICP- 45 × Indira Hari and ICP- 54 × Arka Garima. It appeared that the frequency of heterotic crosses as well as magnitude of heterosis was much related with specific combining ability status of crosses. However, consideration of genetic divergence of the parents involved in the crosses along with positive SCA of the crosses would prove to be useful in predicting heterosis in cowpea.