Study of hybrid vigour in rice (Oryza sativa L.)

Line x tester analysis using a set of four females (lines) and ten males (testers) was carried out to estimate the heterobeltiosis for yield and its components in rice. High magnitude of heterobeltiosis was observed for grain yield per plant, grains per panicle, panicle length, days to 50% flowering and 1000 grain weight. Crosses NAUR 1 x Indrayani, NAUR 1 x Pusa Basmati 370 and NVSR 6029 x Pusa Sughandha 5 were found to be most heterotic for grain yield per plant. Simultaneous increase in grains per panicle, panicles per plant and 1000 grain weight, had positive effects towards higher grain yield. The per se performance of hybrids were, in general related to the heterotic response in majority of characters. This indicated that the selection of crosses on the basis of per se performance or heterotic response would be equally important.