Heterosis, Combining Ability and Genetics for Brix%, Days to First Fruit Ripening and Yield in Tomato

Abstract:

A study was conducted on a 10×۱۰ diallel set of tomato excluding reciprocals to find out the extentof heterosis, combining ability and nature of gene action for yield with two important quality traits: brix% anddays to first fruit ripening (DFFR). Significant differences among genotypes were obtained for all three traits.Positive high significant heterosis was found for yield (211.00, 232.00 and 298.00), for brix% (61.04, 106.70 and37.76) and for DFFR (8.92, 9.33 and 6.07) over the mid, the better and standard parent respectively.

Themagnitudes of variance due to general as well as specific combining ability were highly significant indicatingthe importance of both additive and non-additive gene action. However degree of dominance (o g/o s)22revealed the prevalence of a non-additive gene effect. Cross combinations P ×P (0.66), P ×P (7.85) and9752P ×P (1.22) were best specific combiners for brix%, DFFR and yield/plant. Predominance of non-additive gene96action plays a greater role in the inheritance of brix% and DFFR in tomato.

Reference:Middle-East Journal of Scientific Research 2 (3-4): 128-131, 2007