Combining ability, gene action and heritability analysis for early blight resistance, yield and quality traits in tomato (Solanum lycopersicum L.)

Abstract

Nine tomato genotypes were crossed in Line ×Tester fashion to develop 18 hybrids, which, along with their parents and checks were evaluated for early blight resistance, fruit yield and quality of tomato (Solanum lyco-persicum) to know extent of combining ability for the same. IIHR1816 was found to be the best general combiner with significant highest GCA (General Combining Ability) in desirable direction for per cent disease index (-15.71), carotenoids (3.46), lycopene (2.43) and yield (13.13); while, for plant height (3.94), average fruit weight (25.93), fruit length (0.54), fruit breadth (0.63) and pericarp thickness (1.71), the line IIHR2848 was best general combiner. The tester IIHR2852 was a best general combiner for traits like days to 50% flowering (-0.83) and fruit firmness (0.51).The crosses viz., IIHR2891 × IIHR2853 (11.61), IIHR2850 × IIHR2852 (11.40) and IIHR2892 × IIHR2890 (11.19) were found to be superior specific combiners for yield. IIHR2892 × IIHR2852 was a superior specific combin-er for fruit quality traits like fruit firmness (0.98), total carotenoids (6.95) and lycopene (4.52).Best specific combiners for early blight resistance were IIHR2850 × IIHR2852 (-9.58), IIHR2891 × IIHR2890 (-9.58) and IIHR2892 × IIH-R2890 (-6.82). The experiment helped in identifying these superior general combiners and specific combiners for early blight resistance, coupled with good yield and quality of the crop, which can be used in further breeding under-takings.