Genetic behavior of earliness and yield traits of some rice (Oryza sativa L.) genotypes

Rice (Oryza sativa L.) is a critical staple food crop that provides more than half of the world's population with its primary nutritional source. Breeders and growers of rice would profit from robust genotypes with improved morphological and yield-related characteristics. The aim of this work is to determine the nature and magnitude of gene action on yield quantity and quality, to define the best combinations of earliness and yield characters, develop hybrids that perform better on yield quantity and quality. Three replications were used in the experiment's randomized complete block design (RCBD). During the 2016 season, seven different parents, namely Sakha 101, Sakha 104, Sakha 105, Giza 177, Black rice 1, Black rice 2, and Black rice 3, were crossed using A7 × 7 half-diallel set analysis without reciprocals to generate 21 F1 crosses. The results indicated that genotype-dependent mean squares were very significant for main characteristics. Significant combining ability SCA variance estimates were more considerable than generalcombiningability(GCA) variance for all characters except days to 50% flowering. It demonstrated that both additive and non-additive genetic variance played a role in expressing the attributes investigated. The Parents, Black rice, Sakha 105, and Sakha 101, were recognized as the best general combiner for most growth and yield attributes. Sakha105 × Black Rice 1, Sakha105 × Black Rice 2, Sakha101 × Sakha104, Sakha105 × Giza 177, and Sakha101 × Giza 177 all demonstrated non-additive gene activity for the majority of maturity and yield traits. Heterosis breeding would be most efficient for qualities where high performance was determined by dominance and dominance gene effects. The increased yield of crosses results from parents with a diverse genetic background and genetic diversity.