Variability and association studies in tomato germplasm under high-temperature arid region.

Genetic variability and correlation studies were carried out for 12 traits in 23 genotypes of tomato grown during spring-summer of 2009 under hot, arid agro-climatic conditions. Genetic variability, heritability and expected genetic advance revealed significant differences for all the traits studied. PCV and GCV were high for fruit weight, number of fruits per plant, plant height and fruit yield per plant. High heritability with high genetic advance as percentage of mean was observed for yield per plant (93.2%) as also for average fruit weight (92.8%), number of fruits per plant (73.4%) and plant height (50.1%) indicating the role of additive gene effects and for effectiveness of selecting for these traits. Correlation studies revealed that fruit yield had significant positive correlation with fruit weight, fruit length, fruit diameter and number of fruits per plant, both at the genotypic and phenotypic levels, indicating mutual association of these traits. Negative correlation of days to flowering and days to first harvest on yield per plant suggested indirect selection for earliness for yield improvement.