Study of heterosis over environments in tomato (Solanum lycopersicum L.)

A study was conducted in tomato to estimate the magnitude of heterosis for yield and its fourteen yield components. 32 F1 hybrids generated by line x tester mating design comprising of eight lines and four testers and these F1 along with 12 parents and one commercial check ‘Abhinav’ were evaluated at three research stations viz., (Navsari, Surat and Hansot) of Navsari Agricultural University, Navsari, Gujarat (India) during late kharif- 2014-15 in randomized block design with three replications. The analysis of variance showed significant differences among the genotypes for all the traits. There was high heterosis in most of the hybrids which support the role of non-additive gene effects. Among the crosses, AVTO-5 x GT-2 showed high sca effect for fruit yield over environments. The maximum standard heterosis over commercial check was exhibited by the cross AVTO-5 x GT-2 followed by AVTO-7 x GT-2, AVTO-5 x JT-3, JTL-12-12 x GT-2 and JTL-12-12 x JT-3 for fruit yield and its one or more important component traits. In direct selection for traits such as plant height, number of clusters per plant, number of fruits per plant and average fruit weight could be done in order to achieve higher yield through heterosis breeding.