Estimation of Heritability and Association Analysis of Agronomic Traits Contributing to Yield on Upland Rice (Oryza sativa L.)

Rice (Oryza sativa L.) is an important commodity with a major influence on the country's economy. Plant breeding activities must be conducted to develop high-yielding potential genotypes with desired agronomic traits. The purpose of this research is to study the heritability and coheritability of agronomic traits as well as to study the direct and indirect effects through genotypic and phenotypic correlations among agronomic traits contributing to yield on genotypes of rice. The research was carried out from March to July 2022 at the Experimental Field of the Faculty of Agriculture, Brawijaya University, Jatimulyo, Lowokwaru, Malang, East Java. Ten genotypes of rice were used as genetic materials. The research used a Randomized Block Design (RBD) method with 3 replications. Data were analyzed using analysis of variance, analysis of covariance, and path analysis. The results revealed that there were very significant differences among upland rice genotypes for all observed traits. All observed agronomic traits had high heritability estimates. Plant height with time of inflorescence emergence had the highest coheritability, and flag leaf length with yield per plot had the lowest coheritability. The traits of the number of spikelets per panicle and weight of milled dry grains positively correlated with yield. Weight of milled dry grains had the highest positive direct effect through genotypic correlation and phenotypic correlation with yield.