Studies On Genetic Variability In Agronomic And Fruit Quality Traits Among Some Tomato (Solanum Lycopersicum L.) Genotypes

ABSTRACT

In the present study, a total of twenty (20) tomato genotypes were evaluated simultaneously under greenhouse and field conditions in order to determine genetic variability present in the agronomic and fruit quality traits. The experiments were laid out in a Randomized Complete Block Design (RCBD) with three (3) replications. Both individual and combined analyses of variance were employed. The individual analysis of variance showed a significant (P < 0.01) variability among the genotypes for almost all characters studied. The components of variance estimated on individual location basis indicated a moderate to high GCV, high broad sense heritability as well as high genetic gain for almost all traits. However, stem diameter, pH and gallic acid recorded low estimated GCV under greenhouse conditions while plant height, stem diameter, chlorophyll content, number of days to 50 % flowering, fruit set percentage, number of days to fruit maturity and pH recorded lower estimates for GCV under field conditions. The combined analysis of variance (ANOVA) showed significant (P < 0.01) difference among the genotypes, locations and their interactions. The component of variance based on a two-factor analysis of variance revealed considerable effect of location and Genotype x Location interaction on the expression of traits especially, fruit phytochemical composition traits. Relative performance of the genotypes differed with location. Among the genotypes evaluated, MONGAL F1, PLATINUM F1, NKANSAH HT, WOSOWOSO, ROMA and SUMO F1 displayed superior performance for fruit yield across all locations. Large variation was observed among the genotypes for all fruit quality traits studied. Genotypes produced under greenhouse conditions recorded higher amounts of flavonoid composition while phenolic acids content were higher among field-produced tomato genotypes. Number of trusses per plant, number of fruits per plant as well as total fruit weight per plant showed a positive significant association with fruit yield under both greenhouse and field conditions. Consistency of correlation across the two locations was observed. However the correlation coefficients differed due to the effects of G x L interaction.