GENETIC VARIABILITY AND DIVERGENCE ANALYSIS IN SOME INBRED LINES OF MAIZE (Zea mays)

Abstract

The field experiment was conducted in the experimental field of Department of Genetics and Plant Breeding, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh during the period from November 2012 to April 2013 to study the genetic variability and diversity of maize inbred lines. In this research work, the seeds of 30 maize genotypes were used viz. ML1, ML2, ML3, ML4, MLS, ML6, ML7, MLS8, ML9, ML10, ML11, ML12, ML13, ML14, ML15, ML16, ML17, ML18, ML19, ML20,ML21, ML22, ML23, ML24, ML25, ML26, ML27, ML29 and ML30. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. Mean performance, variability and divergence analysis were done on yield and yield contributing characters namely, days to 50% tasseling, days to 50% silking, days to maturity, plant height(cm), cob height(cm), cob length(cm), cob girth(cm), no. of cob per plant, cob weight(gm), 100 grain weight(gm) and grain yield per plant. The highest grain yield per plant (240g) was recorded from ML15 again the lowest (114.1g) was found from ML21. Analysis of variance reveal that, days to 50% tasseling (14.76), days to maturity (6.96), plant height (436.77cm), cob length (3.83cm), cob girth (0.71cm), cob per plant (0.05) and cob weight(1815.04gm) are significant at 5% level of probability. On the other hand 100 grain weight (78.32gm) and yield per plant (1919.95gm) are significant at 1% level of probability. Phenotypic variance (2929.26) was higher than genotypic variance (-504.65) which was supported by moderate difference between phenotypic (39.74%) and genotypic (-27.21%) coefficient of variation. Low heritability (-17.23) was supported by low genetic advance over mean (- 10.35). All the genotypes were clustered in 6 groups. Cluster III was the largest cluster comprising of 12 maize genotypes and cluster I] comprised only one genotype. Cluster distances are the approximate measure of cluster divergence. Cluster III had highest intra cluster distance (7.11) and Cluster V had lowest intra cluster distance (4.43). Inter cluster distance was maximum (8043.27) between cluster V and cluster II.