HIGH PARENT HETEROSIS AND EVALUATION OF TOMATO (Solanum lycopersicum, L.) HYBRIDS INCORPORATING THE MUTANT RIN GENE

Abstract

This investigation was conducted in the research facilities of the Horticulture Research Institute during the period from 2003 to 2006 to produce and evaluate some tomato hybrids having ripening inhibitor mutant gene rin and study effect of this gene on some quality characters, yield and fruit shelf life. Twenty four tomato cvs. were crossed as female parents with Incridible cv. as male parent. The cultivar Incridible carries rin mutant gene. Parents and F1 populations were planted in RCBD with 4 replicates in two successive summer seasons 2005 and 2006 in open field to evaluate them. It was found that the hybrids Black From Tula I Incridible and VFNT I Incridible produced the highest significant early yield (7.7 and 6.85 ton /feddan, respectively). Nine hybrids out of them exhibited significant positive high parent heterosis for early yield ranged from 36.81 to 146.79% with the hybrid Black From Tula I Incridible having the highest value. The hybrid Strain B I Incridible produced the highest total yield (17.54 ton/fed.) over all evaluated genotypes; the hybrid Packmore BI Incridible exhibited the highest positive high parent heterosis for the same trait. The cultivar Polish produced the highest significant average fruit weight over all evaluated cvs. with mean value 241.4 g. The cultivars Black From Tula, ranked second in this trait having mean value being 205.8g, the two hybrids VFNT I Incridible and Castle King I Incridible showed significant positive high parent heterosis. The cultivar Incridible significantly was the highest value among all evaluated genotypes in fruit firmness, fruit firmness during 35 days, and storage ability. All of the evaluated hybrids were not superior in fruit firmness compared to high parent where they showed significant negative high parent heterosis for these traits.