Abstract

                                The present study was conducted to estimate relative heterosis, heterobeltiosis and standard heterosis of cross components in rice genotypes under sodicity. All three types of heterosis were worked out through diallel analysis of 30 hybrids developed by crossing six parents to know the genetic architecture of 14 physio-morphological traits viz., days to 50 percent flowering, plant height, number of productive tillers per plant, panicle length, number of filled grains per panicle, spikelet fertility percentage, 100 grain weight, single plant yield, dry root weight, dry shoot weight, root: shoot ratio, Na+: K+ ratio, chlorophyll content and proline content under sodic environment. On perusal of data for hybrids based on per se, sca effects and standard heterosis, five hybrids viz., FL 478 / IW Ponni, IW Ponni / IR 64, IW Ponni / BPT 5204, BPT 5204 / FL 478, IW Ponni / FL 478 were found to be suitable for heterosis breeding under sodicity. As there was dominance gene action involved, inter se mating followed by recombination breeding might be advocated for improvement of yield, its components and physiological traits under sodicity

Key words : : : Rice, Sodicity, Diallele, Relative heterosis, Heterobeltiosis, Standard heterosis..