Vol. 11, Issue 7 (2022)

Author(s):
MM Dodake, CG Intwala and PB Patel

Abstract:
The present investigation was carried during Kharif 2021 at Navsari Agricultural University, Navsari (Gujarat) to estimate the combining ability and to determine the nature and magnitude of heterosis for yield and yield component traits in rice. The experimental material consisted of 28 hybrids produced by crossing seven lines with four testers in Line x Tester design. Analysis of variance for combining ability revealed that, mean squares of lines, testers and line x testers was highly significant for the traits like productive tillers per plant, grains per panicle, kernel length and 100 grain weight indicated that these traits were governed by both gene actions, among which the predominant gene action was additive for the former three traits while, non-additive for latter last one in pooled over the environments. The other traits viz., days to 50 per cent flowering, panicle length, grain yield per plant and straw yield per plant were governed by additive gene action whereas, plant height, kernel breadth, L:B ratio, protein content and amylose content were governed by non-additive gene action. Among the parents; NVSR-418, NWGR-15018, NVSR-6172 and NVSR-494 were good general combiners for grain yield per plant and most of the yield components. The parents viz., NVSR-496, NVSR-418, NVSR-2103 and NVSR-494 were good general combiners for earliness whereas, parents viz., GNR-3, NVSR-2103, NVSR-496, NVSR-6206 and GR-17 were ideal for dwarf plant stature. In case of heterosis, highly significant and positive heterosis over better parent and standard check for grain yield and its component characters among which, highly significant and standard heterosis suggested that there is ample scope of exploiting heterosis commercially. The hybrid NWGR-15018 x NVSR-418 manifested the highest heterosis over the standard check (37.77%) with high grain yield per plant followed by NVSR-453 x NVSR-418 (33.58%), NVSR-6206 x NVSR-418 (31.47%) and NVSR-494 x NVSR-418 (31.33%) while hybrids, NVSR-453 x NVSR-418 exhibited higher heterobeltiosis (36.30%) followed by NVSR-6206 x NVSR-418 (34.15%), NWGR-15018 x NVSR-418 (33.70%) and NVSR-494 x NVSR-418 (32.79%) over the environments.