Genetic control of morphological traits in tomato fruits

This study was carried out to investigate the inheritance of the tomato fruit shape and other morphological traits in a single (biparental) cross among Nemadoro and Stevens cultivars. The F1, F2 and backcross to both parents generations were obtained and evaluated along with the parental lines in a randomized complete block design with four replications. Mean and variance estimates of genetic parameters were obtained using the models proposed by Mather and Jinks (1982). Genes controlling morphological tomato fruit traits predominantly showed additive effects, but partial dominance was also often displayed. The narrow sense heritability estimate for fruit shape, evaluated by the length/diameter ratio, was 50.18%. The narrow sense heritability at the individual plant level for average fruit weight and number of loculi were high, 67.08% and 87.46%, respectively, indicating favorable conditions for selecting these traits. The additive dominant model was adequate to explain the inheritance of fruit length, pericarp thickness, fruit length/diameter ratio and average locule weight.