COMBINING ABILITY AND GENE ACTION STUDIES FOR YIELD AND ITS ATTRIBUTING TRAITS OVER DIFFERENT ENVIRONMENTS IN TOMATO (SOLANUM LYCOPERSICUM L.)

The development of high-yielding hybrids, varieties, genetic improvement, and optimal selection are key goals of an effective breeding program.Consequently, a study was carried out to evaluate the combining ability for yield and yield-contributing traits in tomato genotypes.The present research was undertaken to examine the combining ability of 11 parents and 28 hybrids that resulted from crossing of seven lines and four testers in line tester mating design, for yield and quality governing traits in tomato over three different locations.Analysis of variance for combining ability revealed highly significant differences for mean square of SCA for all studied characters and GCA for fruit girth (cm).The ratio of 2 GCA/ 2 SCA was lower than unity for fruit girth (cm) indicate the pre dominant role of non-additive gene action for inheritance.For fruits per plant and fruit yield per plant (kg), parents viz., DVRT-2 and GT-6 exhibited significant and positive GCA effects.In majority hybrids DVRT-2 and GT-6 reflects positive effects for getting higher yield.An analysis for the specific combining ability effect revealed that the hybrids viz., NTL-42 DVRT-2, NTL-25 AT-3, NTL-25 DVRT-2, NTL-45 GT-6 and NTL-19 GT-6 was found positive and significant SCA effect for fruit yield per plant (kg) in all the three locations.