Genetic study for earliness in cowpea (Vigna unguiculata L. Walp.)

Line x Tester (10x3) analysis of F₁ generation in cowpea expressed highly significant differences among parents and hybrid for days to 50% flowering and days to 1^st green pod picking. The cross combination Black Seeded x Pusa Komal showed maximum negative heterosis over better parent and mid parent, whereas Kala Zamala X Cowpea263 was better over standard parent for days to 50% flowering. The crosses, Ramnagar Kala x Arka Garima, Red Seeded x Arka Garima and Red Seeded x Cowpea-263 showed maximum negative heterosis over better parent, mid parent and standard parent, respectively for days to I^st green pod picking. The variance due to general combining ability and specific combining ability were highly significant denoting importance of additive and non-additive gene action for both the traits. Additive genetic variance was predominant for days to 50% flowering whereas nonadditive genetic variance governs days to I^st green pod picking. The parents NDCP-13, Kala Zamala, Red Seeded, Black Seeded, RCV-7, Cowpea-263 and Pusa Komal were good general combiners for both the traits. The crosses Sel. 2–2 x Pusa Komal, Cowpea Local x Arka Garima and Sel. 2–1 x Arka Garima were identified as best specific combiners for days to 50% flowering whereas crosses Sel. 2–2 x Pusa Komal, Cowpea Local x Arka Garima and Red Seeded x Arka Garima were good for days to I^st green pod picking.