Combining Ability Analysis For Yield And Yield Components In F2 Populations Of Rice (Oryza Sativa L.)

Abstract

This study was conducted to investigate general and specific combining ability in F2 populations of rice. The twenty-one F2 populations developed through half diallel mating design and their seven parental lines were sown in the field in three replications at field of Nuclear Institute of Agriculture (NIA), Tandojam, during the Kharif season 2019-20. The analysis of variance results revealed that genotypes, parents, and hybrids mean squares differed significantly (P>0.01) for all studied characters except for the trait yield plant-1, which was non-significant for hybrids. Among the seven parents; minimum days to initial heading (95.07) and days to 90% maturity were recorded in KSK-282, while minimum plant height (94.33 cm) was recorded in IR-6; the maximum number of tillers plant-1 was recorded (21.93) in NIA-102, the maximum panicle length (30.15 cm), total grains panicle-1 (260.88), and grain yield plot-1(12.15 kg) were recorded in Shandar; the maximum panicle weight (4.81 g) and thousand grain weight (33.85 g) was observed in parental line NIA-19/A. Among twenty one hybrids, minimum days to initial heading (97.40) and days to 90% maturity were recorded in cross NIA-19/A × KSK-282; minimum plant height (92.73 cm) was recorded in IR-6 × KSK-282; maximum number of tillers plant-1 (22.80) and panicle length (29.46 cm) were recorded in Shandar × NIA-102; the highest grainspanicle-1 (295.32) was obtained in Shandar × Shadab; the maximum 1000 grain weight (32.66 g) was recorded in Shandar × NIA-19/A; while maximum yield plot-1 (12.58 kg) was obtained in Shua-92 × Shadab. It is concluded from this study that among seven parental lines KSK-282 was found as good general combiner for traits days to initial heading, days to 90% maturity and plant height; Shandar proved good general combiner for traits panicle length, panicle weight and total grains panicle-1, while NIA-102 and NIA-19/A were proved as good general combiners for number of tillers plant-1 and thousand grain weight, respectively. Among 21 hybrids, Shua-92 × Shadab proved to be good specific combiner for panicle length, and yield plot-1, Shandar × Shua-92 proved good specific combiner for panicle weight and thousand grain weight. In contrast, Shandar × NIA-102, NIA-19/A × KSK-282, Shandar × Shadab, Shadab × KSK-282, and NIA-19/A × Shadab proved good specific combiners for days to initial heading, days to 90% maturity, dwarf plant height, number of tillers plant-1, and thousand grain weight respectively. These seven cross combinations are identified as superior crosses and can be utilized in future breeding programs for hybrid crop development.