Genetic variability and interrelationship of traits in F3 progenies of tomato (Lycopersicon esculentum Mill.) under cold desert of Leh-Ladakh.

A study was conducted during April to September, 2005 at Field Research Laboratory of Leh-Ladakh to evaluate sixteen bacterial wilt resistant F3 progenies of tomato (Lycopersicon esculentum Mill) for high yield and quality traits. Observations were recorded on the following traits: plant survival, days to 50% flowering, days to first harvest, gross yield per plant, total fruits per plant, marketable fruits/yield per plant, average fruit weight, polar and equatorial diameter, pericarp thickness, locules per fruit, plant height, duration of fruit harvest and total soluble solids. Analysis of variance revealed significant differences among the progenies for all the traits except for incidence of bacterial wilt disease. The progenies BT-18xSUN7611-8, Hawaii7998xSUN7611-1, Hawaii7998xSUN7611-2 were adjudged best for marketable fruits and yield per plant and also possessed desirable horticultural attributes along with bacterial wilt resistance. The phenotypic coefficient of variation and genotypic coefficient of variation estimates were moderate for most of the traits. The estimates of heritability were in general high to moderate whereas genetic advance was moderate to low. Marketable yield per plant was positively and significantly correlated with total fruits per plant, marketable fruits per plant and gross yield per plant. Path coefficient analysis revealed that marketable fruits per plant had maximum (0.85) direct effect on marketable yield per plant followed by average fruit weight (0.35) and pericarp thickness (0.32). From the present study, it was concluded that marketable fruits/plant followed by average fruit weight and pericarp thickness are the primary component traits on which selection shall prove most effective under cold desert of Ladakh.