Received: 03 Jun 2020 Accepted: 19 Jun 2020 Revised: 16 Jun 2020 https://doi.org/10.37992/2020.1102.094 Vol 11(2):574-580 574 Electronic Journal of Plant Breeding Research Article Estimation of variability, heritability, genetic advance and assessment of frequency distribution for morphological traits in intercross population of maize C. Neelima 1 , C. Sarankumar 2 , M. Sudha 1 , K. N. Ganesan 3 , R. Ravikesavan 4 and N. Senthil 2* 1 Department of Plant Biotechnology. Centre for Plant Molecular Biology and Biotechnology, 2 Department of Plant Molecular Biology and Bioinformatics, Centre for Plant Molecular Biology and Biotechnology, 3 Department of Genetics and Plant Breeding, 4 Department of Millets, Centre of plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India *E-Mail: senthil_natesan@tnau.ac.in Abstract Genetic variability analysis is an essential criterion in the selection of crops for improvement programmes and components like Phenotypic Coefcient of Variation, Genotypic Coefcient of Variation, heritability and Genetic Advance as percent of Mean are useful for the exploitation of variability. Skewness and kurtosis indicate the type of gene action and the number of genes governing the trait and selection can be done based on these values. In the present study, variability, heritability, genetic advance, skewness and kurtosis were assessed for the intercross (IC 2 ) population of (UMI1200×CE477) × (UMI1200×VQL1). Fourteen biometrical traits were recorded and the mean values were used for further analysis. Higher PCV values were obtained compared to their respective GCV values for all the traits of the population. Cob length (83.28% and 2.09%) showed the highest heritability and genetic advance suggesting higher genetic gain, which can be improved with simple selection methods and hence, showing additive gene action. Single plant yield showed higher heritability (77.29%) with low genetic advance (0.80%) and hence, requires appropriate selection methods to improve the genetic gain. With the exception of days to tasseling, all the traits showed platykurtic distribution suggesting that the large number of genes are involved in governing the traits. Days to silking, tassel length, the number of tassel branches, leaf length, leaf breadth, cob length, the number of kernels per row, cob weight, 100 kernel weight and single plant yield showed positive skewness suggesting dominant based complementary epistasis and hence, rapid genetic gain can be obtained by intense selection. Days to tasseling, plant height, ear height and the number of kernel rows per cob negative skewness showing duplicate gene action and hence, the rapid genetic gain can be obtained by mild selection. Keywords Genetic variability, heritability and GAM, skewness, kurtosis, maize INtRoduCtIoN Maize is one of the primary cereal crops that is grown throughout the world for its binary relevance in diet as well as livestock feed (Gwirtz et al., 2014). As a result of its nutritional importance, diversity, wide adaptability and higher productivity potential, maize is a staple in many parts of the world. Normal maize is low in Vitamin A and certain essential amino acids like lysine and tryptophan. Owing to its wide usage, there is an urgent need to fortify maize with the defcient nutrition. Several studies have been aimed at improving the nutrition in maize (Muthusamy et al., 2014, Hossain et al., 2018, Pukalenthy et al., 2019 and Chandran et al., 2019). The improvement