Character Association and Path Coefficient Analysis of Grain Yield and its Contributing Traits in Maize (Zea mays L.) Genotypes

Aim: The present study was undertaken to assess the magnitude and nature of the associations between grain yield and its contributing traits in maize genotypes and to identify the key traits influencing grain yield through correlation and path coefficient analysis. Methodology: A total of 48 maize genotypes, comprising 36 hybrids and 12 parental lines, were evaluated using a randomised block design with three replications. Data were recorded for 11 quantitative traits. Results: Genotypic correlation coefficients were generally higher than their corresponding phenotypic coefficients, indicating that the observed associations were partly influenced by environmental effects. The number of kernels per row exhibited the strongest statistically significant positive correlation with grain yield (kg/ha) at both the genotypic (0.8057) and phenotypic (0.8734) levels, followed by ear length (0.8626 and 0.7670), ear height (0.7627 and 0.6862), plant height (0.7624 and 0.6744), 100-seed weight (0.6893 and 0.5981), ear girth (0.6891 and 0.5976), and number of kernel rows per ear (0.4414 and 0.3142), respectively. In contrast, days to 50% tasselling, days to 50% silking, and days to maturity exhibited negative associations with grain yield at both genotypic (−0.5893, −0.5871, and −0.6148, respectively) and phenotypic (−0.7889, −0.7949, and −0.8018, respectively) levels. Path coefficient analysis revealed that number of kernels per row exhibited the highest positive direct effect on grain yield at both genotypic (0.9399) and phenotypic (0.3928) levels followed by number of kernel rows per ear (0.4552 and 0.1767) and 100-seed weight (0.3922 and 0.1820), respectively. Conclusion: The strong positive associations of number of kernels per row, ear length, plant height, ear height, ear girth, and 100-seed weight with grain yield, together with the favourable direct effects of number of kernels per row, number of kernel rows per ear, and 100-seed weight, suggest that these traits could serve as useful selection criteria for improving grain yield in maize. The integration of these traits into selection programmes could improve the effectiveness of identifying superior, high-yielding maize genotypes.