Exploring Hybrid Vigor, Inheritance Patterns, and Genetic Progress in Tomato.

In the present investigation, six tomato pure lines were crossed in half diallel mating design to produce 15 F₁ hybrids. Six parental genotypes and their fifteen hybrids were evaluated in open field in the two summer successive seasons 2022 and 2023. Significant differences among genotypes were observed in mean performance for all studied traits. Both parental lines BS and PE showed significant negative general combining ability effects (GCA) for days to 50% flower anthesis (DF), indicating that both lines could be considered as good combiners for developing early tomato genotype. Also, the parental line PE have significant positive general combining ability (GCA) effects for number of fruits/plant (NF), fruit length (FL), fruit flesh thickness (FSI), titratable acidity% (TA) and marketable yield/plant (MY). The parental line M-G have considerable significant positive GCA effects for fruit diameter (FD), titratable acidity% (TA) and marketable yield/plant (MY). Also, R4 have significant positive GCA effects for fruit weight (FW), fruit length (FL), fruit diameter (FD) and total soluble solids (TSS). The cross SM M-G have significant SCA effects for earliness, (NF), (FW), (FL), (FD), number of locule (NL), (TSS), ascorbic acid (AA) and marketable yield/plant (MY) and reflected favorable significant positive MP and BP heterosis value 83.67 and 73.08% respectivelyfor (MY). The value (H1/D)^1/2 on the all traits was more than one indicating over-dominance. The parental genotypes displayed a greater prevalence of dominant alleles in their genetic makeup (KD/KR) compared to recessive alleles, indicating a higher proportion of dominant alleles across all studied traits.