Genetic studies of quantitative traits through Hayman’s approach in rice

Genetic components of variation were estimated for yield, its components and quality traits through Hayaman's approach of 8 x 8 diallel set. All the components of yield and yield except 1000 grain weight were under the influence of non-additive gene action. Kernel dimensions (length, breadth and length / breadth ratio) were largely under the control of additive gene effects. The proportion of dominant and recessive genes and genes with +ve and -ve effects were not in symmetry as per the estimates of H2/4H1 and KD/KR. Coefficient of regression (b) was found to be significantly different from zero for plant height, panicle length and kernel breadth, which indicated that these traits satisfied the general assumptions of diallel analysis. Based on the results, progeny selection was suggested for improvement of 1000-grain weight and quality traits and for other traits only
population improvement methods were the ideal approach. The parents viz., MTU 4870, JGL-1881 and white ponny were identified as good parents for hybridization.