GENETIC VARIABILITY AND DIVERSITY STUDIES IN MAIZE (Zea mays L.) INBRED LINES

Abstract

Thirty inbred lines of maize were evaluated for ten parameters at the experimental field of Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh during November 2016-April 2017 to study the genetic variability and diversity in maize inbred lines. The experiment was laid out in randomized complete block design (RCBD) with three replications. Mean performance, variability, heritability, coefficient of variation and diversity analysis of yield and yield contributing characters namely Cob height, plant height, cob length, cob diameter, number of kernel rows per cob, number of kernels per row, number of kernels per cob, 1000 kernels weight, yield per plant and pith weight were performed. The highest weight of 1000 kernels (494.3g) was obtained from ML28, the lowest weight of 1000 kernels (213.96g) was recorded from ML21, 1000 kernels weight of phenotypic variation (82.24) was higher than the genotypic variation (18.65) which indicates high environmental effect was supported by narrow difference between phenotypic (23.64) and genotypic (5.36) co-efficient of difference. Weight of 1000 kernels had inherent potential among the genotype high heritability (68.83) for this trait along with high genetic advance in percentage of mean (33.51). All the genotypes were grouped into four clusters. Cluster II was the largest cluster comprising of sixteen maize genotypes followed by cluster I (9) and III (4). Cluster distance denotes by the average inter and intra cluster distance are the approximate measure of the cluster divergence. The maximum (8.34) inter-cluster divergence was observed between the clusters II and IV and it was minimum (3.94) between clusters I and III. The maximum value of inter –cluster distances indicated that the genotypes belonging to the cluster II is far diverged from those cluster IV. Genotypes of cluster II show high intra cluster distance indicating high degree of divergence among the genotypes and also mean performance of genotypes of cluster II show higher result in case of plant height and yield per plant. High degree of performances like plant height, thousand kernel weight and yield per plant with diversified genotypes of cluster II are suitable for selection as parents for future hybridization program.