Evaluation of genetic diversity, variability, character association and path analysis in diverse inbreds of maize (Zea mays L.)

Maize is an important crop after rice and wheat in terms of acreage and ranks second in terms of total production and productivity. The present investigation was carried out during Kharif 2010, involving 70 diverse inbreds collected from different locations. Genetic diversity, variability, association of yield with other component traits and relative importance of direct and indirect effects of different components on yield were assessed. Grouping of genotypes based on biometrical traits led to the formation of ten clusters. The cluster I consisted of 19 inbreds, cluster II consisted of 12 inbreds, while cluster III consisted of eight inbreds followed by cluster IV to X consisting of 1,2,7,3,6,9 and 7 inbreds respectively. The genotypes studied showed a wide range of variation for all the characters. Among the traits evaluated ,maximum genotypic and phenotypic coefficients of variation were observed for grain yield per plant followed by number of rows per cob and number of kernel per row. The estimates of heritability and genetic advance as per cent of mean was high for grain yield per plant, number of kernels per row and number of rows per cob. Grain yield per plant was positively and significantly correlated with cob weight, hundred kernel weight, number of kernel rows per cob and number of kernels per row. Path coefficient analysis further revealed that number of kernel rows per cob exhibited maximum positive direct effect followed by cob length. The significant association of grain yield per plant with hundred kernel weight and number of kernels per row is due to positive indirect effects through number of kernel rows per cob, days to 50% silking, plant height and cob length.