Correlation and Path Coefficient Analysis for Grain Yield and Nutritional Traits in Biofortified Rice (Oryza sativa L.)
K. Ramakrishna Vital *
Department of Genetics and Plant Breeding, Agricultural College, Bapatla-522 101, Andhra Pradesh, India.
Y. Suneetha
Department of Genetics and Plant Breeding, Agricultural College, Bapatla-522 101, Andhra Pradesh, India.
J. Dayal Prasad Babu
Department of Genetics and Plant Breeding, Agricultural College, Bapatla-522 101, Andhra Pradesh, India.
C. N. Neeraja
Department of Genetics and Plant Breeding, Agricultural College, Bapatla-522 101, Andhra Pradesh, India.
*Author to whom correspondence should be addressed.
Abstract
Biofortification in rice (Oryza sativa L.) is a sustainable approach to addressing micronutrient malnutrition; however, developing high-yielding biofortified varieties requires a thorough understanding of the interrelationships among yield components and nutritional traits. The present study was conducted during kharif 2025 at the Regional Agricultural Research Station (RARS), Maruteru, Andhra Pradesh. It used correlation and path coefficient analyses to evaluate 18 traits in 34 biofortified rice genotypes and determine the associations between yield components and nutritional quality. The experiment was laid out in an alpha-lattice design with two replications. Genotypic correlation analysis revealed that ear-bearing tillers per plant, panicle length, grains per panicle, test weight, hulling percentage, milling percentage, head rice recovery, amylose content, protein content, iron content, and zinc content exhibited positive and significant associations with grain yield per plant. In contrast, days to 50 per cent flowering, days to maturity, and plant height showed negative associations with grain yield per plant. Path coefficient analysis revealed that grains per panicle, test weight, milling percentage, amylose content, iron content, and zinc content exerted high positive direct effects on grain yield per plant and showed strong positive correlations, whereas the remaining positively correlated traits contributed primarily via indirect effects. Furthermore, a low genotypic residual effect of 0.1590 indicated that the 18 evaluated traits accounted for 97.47% of the total genotypic variability in grain yield per plant, confirming the adequacy of the traits chosen for path analysis. Since grains per panicle, test weight, milling percentage, amylose content, iron content, and zinc content exhibited both strong positive correlations and high positive direct effects on grain yield, direct selection for these traits is recommended as an effective strategy for the simultaneous improvement of grain yield and micronutrient density in rice breeding programmes.
Keywords: Biofortified rice, Oryza sativa, grain yield, genotypic correlation, path coefficient analysis, iron content, zinc content, grain quality, milling percentage, yield components