Sharma, DeepakSarawagi, A.K.Guhe, ArtiSaxena, Ravi R.Toppo, Ranjeeta2016-12-222016-12-222010115 p.http://krishikosh.egranth.ac.in/handle/1/92100A study entitled “Combining ability and heterosis analysis for identifying elite parents and hybrids in rice (Oryza sativa L.)” was conducted at Research Farm, Department of Plant Breeding and Genetics, Indira Gandhi Krishi Vishwavidyalaya, Raipur Chhattisgarh during Rabi season 2008-2009 and Kharif 2009 to evaluate the variability, to estimate the GCA of parents and SCA of hybrids, to assess the magnitude of heterosis for various yield and related traits and to identify the maintainers and restorers for CMS lines under study. The experimental material includes three CMS lines viz., IR 58025A, CRMS 31A and CRMS 32A and five parents viz., IR 68544-29-2-1-3-1-2, NDR 2067, R 1454-80-49-5-1, Jauphool (Selection) and MTU 1010 as testers and fifteen hybrids were generated in line x tester pattern for the estimation of various genetic parameters, combining ability and two types of heterosis. These hybrids and parents were raised in Randomized Complete Block Design (RCBD) with two replications. The data obtained was subjected to line x tester analysis. Combining ability analysis and heterosis was worked out for characters, days to 50% flowering, plant height, productive tillers per plant, panicle length, pollen fertility (%), spikelet fertility (%), total number of spikelets per plant, thousand grain weight and grain yield per plant. The analysis of variance revealed the predominance of non-additive gene action for the all characters under study, which suggested that it is possible to exploit heterosis from the material used. Among the CMS lines studied, it was revealed that only one line IR 58025A was found to be the good general combiner and among testers R 1454-80-49-5-1, NDR 2067 and IR 68544-29-2-1-3-1-2 were found to be superior general combiners for yield and attributing characters. The hybrids IR 58025A/R 1454-80-49-5-1, CRMS 32A/MTU 1010 and CRMS 32A/Jauphool (Selection) were identified as a good combinations on the bases of SCA effects, per se performance and high GCA or low GCA effects of the parents for grain yield per plant and its attributes under study. Crosses IR 58025A/R 1454-80-49-5-1, CRMS 31A/MTU 1010 and CRMS 32A/MTU 1010 were identified as good heterotic hybrids for grain yield per plant and other associated traits. These promising hybrids offer greater scope for further exploitation of hybrid vigour commercially. Based on the pollen fertility percent and spikelet fertility percent, three genotypes were identified as potential restorers. Among which two genotypes viz., Jauphool (Selection) and MTU 1010 were identified as potential restorers for one line (CRMS 32A). Where as Jauphool (Selection) is potential restorer for CRMS 31A. The frequency of partial maintainers was higher than restorers.enThesis