GENETIC DIVERSITY ANALYSIS AMONG SOME TOMATO GENOTYPES (Solanum lycopersicum L.)

Abstract

The present study was undertaken at the Sher-e-Bangla Agricultural University Farm, Dhaka-1207, Bangladesh with fifteen genotypes of tomato to study the genetic diversity among them during November 2015 to April 2016. The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. The genotypes were BARI tomato-2, BARI tomato-3, BARI hybrid tomato-4, BARI hybrid tomato-5, BARI tomato-11, BARI tomato-14, BARI tomato-15, BARI tomato-16, BARI tomato-17, BD-7287, BD-7290, BD-7278, BD-7757, BD-9960 and BD-7291. Considering agronomic performance the genotype G13 showed the maximum number of branches plant-1 and number of fruits plant-1, G5 showed the maximum number of fruits cluster-1, G14 for the maximum number of clusters plant-1, G9 for the maximum fresh fruit weight (single) and G4 for the maximum fruit yield plant-1 (kg).The number of fruit yield plant-1 showed the highest range of variation (3.75 kg - 1.05 kg) that means wide range of variation exists for this character. In case of plant height, number of leaves plant-1, number of flowers plant-1, number of fruits plant-1, fruit yield plant-1, showed the higher influence of environment for the expression of these characters. All the characters under the present study exhibited the highest value of heritability. Most of the characters showed the genotypic correlation co-efficient were higher than the corresponding phenotypic correlation co-efficient suggesting a strong inherent association between the characters under study. The significant positive correlation with yield per plant was found in number of branches per plant (0.065 and 0.071), number of flowers plant-1 (0.059 and 0.048), number of fruits plant-1 (0.053 and 0.039), fruit length (0.524 and 0.517), single fresh fruit weight (0.331 and 0.337), percentage of brix (0.139 and 0.142) at genotypic and phenotypic level while the significant negative correlation was found in days to maturity and the number of fruits per cluster at genotypic and phenotypic level. Path coefficient analysis showed that single fruit weight had the positive correlation with fruit yield per plant. Coherently, this trait contributed to the yield through direct effect (0.086) indicating selection would be judicious and more effective for these characters in future breeding program. Positive direct effect was also found in plant height, number of branches plant-1, number of flowers plant-1, days to first flowering, number of clusters plant-1, number of fruits plant-1, fruit length, fruit diameter and dry weight of 5 g fresh fruit. Considering the magnitude of cluster mean and agronomic performance the genotype G13 for the maximum number of branches plant-1, number of fruits plant-1, G5 for maximum number of fruits cluster-1, G14 for the maximum number of clusters plant-1, G9 for the maximum fresh fruit weight (single) and G4 for maximum fruit yield plant-1 (kg) were found promising. Therefore, considering group distance and other agronomic performance the inter-genotypic crosses between G5, G9, G13 and G14 might be suggested for future hybridization program.