Productive Association of Quantitative Traits in Diverse Ecotypes of Rice (Oryza sativaL.)

Genotypic and phenotypic correlations and path coefficients for 16 QTL traits involving seven diverse rice ecotypes with different maturity group in a 7 × 7 half-diallel set of 21 crosses in each F1 and F2 were estimated. The grain yield/plant was found to be associated positively and significantly at both phenotypic and genotypic levels with biological yield, number of total and productive tillers/plant, 100-grain weight and panicle length in F1 while in F2 with biological yield, number of total spikelets/panicle and number of total and productive tillers/plant. The perusal of data inferred that certain traits were intercorrelated among themselves, viz., biological yield with number of total and productive tillers/plant; L/B ratio with 100-grain weight and kernel length. Moderate to high estimates of narrow sense heritability and genetic advance were observed for plant height, days to 50% flowering and 100-grain weight which indicated actions of additive genes in their inheritance. The results were discussed in the sense that strategically planned selection for reduced crop growth period, need-based elongating canopy architecture and bold grained single plant ideotype would be the positive motivations and that application of this novel strategy would lead to increased biological yield vis-à-vis enhanced and sustainable grain yield productivity of both irrigated and low input target rice ecosystems.