Genetic variability and correlation in maize inbred lines under irrigated and moisture stress condition

Abstract

Maize, one of the most widely grown cereals in the world and is called as queen of cereal due to its productivity. The experiment was conducted to assess the extent of genetic variability and correlation for yield and its attributing traits under irrigated and moisture stress conditions (stress imposed during flowering stage) at two locations viz., Department of Millets, TNAU, Coimbatore and Maize Research Station, Vagarai. A total of thirteen biometrical parameters were recorded. High values of GCV, heritability and genetic advance per cent, respectively was noted for the traits Anthesis Silking Interval (ASI) (36.51,78.51 & 66.63%), number of kernels per row (29.08, 80.50 & 53.75%), hundred grain weight (28.54, 82.16 & 53.29%) and yield (21.37, 73.85 & 37.83%) under irrigated condition, and the traits cob yield (29.78, 71.49 & 51.87%), ASI (29.03, 72.52 & 50.93%), hundred grain weight (26.86, 80.76 & 49.73%) and cob placement height (21.34,78.75 & 39.01%) under stress condition. This indicates that the selection based on these traits may be influenced by additive gene action and would be quite effective. The correlation analysis revealed a positive association of the traits hundred grain weight (0.592, 0.536), number of kernels per row (0.430, 0.397), number of kernel rows per cob (0.415, 0.382) and plant height (0.303, 0.316) with grain yield under both ecosystems (irrigated and moisture stress) and these traits can be given importance while the selection of promising individuals for grain yield. Days to 50% per cent tasseling (-0.496, -0.240) and silking (-0.565, -0.358) recorded significant negative association with yield and it can be used for the development of early duration lines. Further the significant negative ASI could be exploited to develop drought tolerant inbred lines in maize. Key words: Zea mays, water stress, ASI, GCV, heritability, genotypic correlation.