CHARACTERIZATION AND GENETIC DIVERSITY OF SPONGE GOURD (Luffa cylindrica L.)

Abstract

The morphological character, genetic diversity, genotypic and phenotypic variance, genotypic and phenotypic coefficient of variation, heritability, genetic advance and genetic advance as percent of mean were studied for 15 genotypes of sponge gourd were determined in a field experiment conducted at the farm of Sher-e-Bangla Agricultural University, Dhaka during April, 2007 to October, 2007. Significant genotypic differences were observed for all the characters studied. The phenotypic coefficient of variation was higher than genotypic coefficient of variation in all the characters. The phenotypic coefficient of variation (FCV) estimates were high for all the characters. Heritability estimates were high for days to seed germination, days to first male flower, days to first female flower, peduncle length, fruit length and no. of seed per plant. In spite of high heritability values for most traits, the expected genetic advance as percentage of mean ranged from 1.14 to 121.30. Multivariate analysis was performed through principal component analysis (PCA); principal coordinate analysis, cluster analysis and canonical variate analysis were used to classify 15 sponge gourd genotypes. As per as PCA, 02 and cluster analysis, the genotypes were grouped into five different clusters. Cluster I and cluster IV had the maximum of four and minimum of one genotypes respectively. The highest inter-genotypic distance was found between 001 and 002 and the lowest distance between 002 and 007. The maximum inter-cluster distance was observed between the clusters IV and cluster V. whereas the lowest-inter cluster distance was found between the cluster I and cluster IV. The highest intra-cluster distance was identified in cluster Ill and the lowest intra cluster distance was found in cluster IV. Genotypes included in cluster I suitable for yield per plant, cluster Ill for having the highest mean value for inter node length, cluster V for leaf length, leaf breadth, petiole length, days to first male flower, days to first female flower, node no. of first male flower, node no. of first female flower and sex ratio. Considering diversity pattern and other agronomic performances the genotypic crosses between GOiand 002; 001 and GOT; 001 and 015: 001 and 004; 001 and 014; 001 and 010; Gil and G 07; 005 and 014: 002 and 003; 004 and Gil, might be used for future hybridization programme