Estimation of combining ability, heterosis, heritability, and generation mean in basmati rice (Oryza sativa L.) by line x tester design

Genetic parameters help to identify the breeding behavior of plants and aids in the selection of elite genotypes for hybridization programs. To determine the nature and type of gene action, to select superior genotypes and best cross combinations, combining ability, heterosis, heritability and five generation mean were estimated based on three susceptible varieties as lines and three resistant genotypes as testers in 2016. The three lines and testers were Pant Basmati-1, Pant Basmati-2, and Pant Basmati-17 and, BBL-180-5-1-4-1, Oryza perennis and improved Pusa Basmati-1 respectively. They were crossed in line x tester mating fashion. The plant progenies were grown up to three seasons to get P1, P2, F1, F2, and F3 to find out five generation mean. The experimental trial showed that all genotypes were significant and showed maximum variations among the traits. The general and specific combining ability values of lines and testers were also significant which prerequisite need for selection of superior genotypes. Maximum heterosis was reported in Pant Basmati-2 x Oryza perennis followed by Pant Basmati-2 x BBL-180-5-1-4-1 and Pant Basmati-1 x Oryza perennis respectively. The Highest heritability was recorded for 100-grain weight and lowest for days to flowering in all crosses. Five generation mean analysis showed epistatic nonallelic gene interactions like dominance and additive x additive gene interactions respectively. The overall results suggested that the selected lines, testers and cross Pant Basmati-2 x Oryza perennis were most appropriate for creating maximum heterosis which showed non-allelic gene interactions.