Assessment of genetic variability in Maize (Zea mays L.) inbred lines for yield and yield related traits

Abstract

This study aimed to assess the extent of genetic variability among maize inbred lines for yield and related traits under low nitrogen conditions. Estimating genetic parameters such as GCV, PCV, heritability, and genetic advance helps determine the genetic potential and inheritance of these traits. High heritability combined with high genetic advance indicates additive gene action, suggesting that selection would be effective for improvement. The investigation was conducted during Rabi 2024 at the College of Agriculture, KSNUAHS, Navule, Shivamogga, India, using a factorial design. Forty maize genotypes along with two checks were evaluated for eighteen characters, including days to 50% tasseling, days to 50% silking, anthesis-silking interval, plant height, number of leaves per plant, ear height, leaf length, leaf width, leaf area, stem girth, ear length, ear girth, number of kernel rows per ear, number of kernels per row, test weight, dry fodder yield per plant, grain yield per plant, and harvest index. Data were recorded and analyzed using R software to estimate variance components, PCV, GCV, heritability, and genetic advance as percent of mean (GAM). Analysis of variance revealed significant differences among genotypes, nitrogen levels, and their interactions for all traits except leaf area with respect to genotype. Traits such as ear height (20.97, 26.84, 61.00, 28.06), leaf width (39.47, 42.05, 88.00, 45.28), stem girth (40.74, 42.35, 92.50, 47.66), number of kernel rows per ear (25.66, 28.80, 79.30, 30.06), and grain yield (23.10, 37.54, 95.20, 43.39) exhibited high GCV, PCV, heritability, and GAM values, indicating the predominance of additive gene action.