Analysis of Grain Yield and Yield Contributing Traits in Maize Inbred Lines through Correlation and Path Coefficient Approaches

Abstract

Grain yield in maize is a complex quantitative trait that is highly influenced by environmental conditions and governed by intricate interactions among multiple yield-contributing characters. The complexity arises from both genetic and environmental factors, making direct selection for yield challenging. Hence, analyzing genotypic and phenotypic correlation coefficients among various agronomic traits is essential to elucidate the nature and extent of their association with grain yield. The present study aimed to dissect the relationships among yield contributing traits and identify key determinants of grain yield in maize inbred lines through correlation and path coefficient analysis. A set of 50 diverse maize inbred lines was evaluated during the Rabi, 2024–25, at the Regional Agricultural Research Station, Lam, Guntur, in an Alpha Lattice Design with two replications. Data were recorded on thirteen traits, including days to 50% anthesis, days to 50% silking, anthesis-silking interval, days to maturity, plant height, ear height, ear length, ear girth, number of kernel rows per ear, number of kernels per row, 100-kernel weight, SPAD chlorophyll meter readings (SCMR) and grain yield per plant. Genotypic and phenotypic correlation analysis revealed significant positive associations of days to maturity, plant height, ear height, ear length, ear girth, number of kernel rows per ear, number of kernels per row, 100-kernel weight and SPAD Chlorophyll Meter Reading (SCMR) with grain yield per plant, indicating their potential utility for indirect selection. Path coefficient analysis indicated that anthesis-silking interval, plant height, 100-kernel weight and SPAD Chlorophyll Meter Reading (SCMR) exhibited positive direct effects on grain yield per plant at both genotypic and phenotypic levels, highlighting their importance in breeding programs. These findings provide critical insights for maize breeders to enhance grain yield through the strategic selection of key traits.