Combining Ability Studies on Yield and Yield Related Traits in Tomato (Solanum lycopersicum L.)

Abstract

Aim: The present study was conducted to generate information regarding the general combining ability (GCA), specific combining ability (SCA), genetic parameters and GCA and SCA variances in tomato.
 Study Design: The parents and F1s were laid out in Randomized block design with 3 replications.
 Place and Duration of Study: The present study was conducted at research farm of Banaras Hindu University, Varanasi. Crosses were generated in Line x Tester design and resultant F1, F2 and parents were evaluated.
 Methodology: After genetic diversity evaluation, ten genotypes were selected and used as females which were crossed with three other selected genotypes used as males in Line × Tester mating design followed by evaluation of their F1 hybrids along with parents.
 Results: The study concluded that Pant T-3 was a good general combiner for plant height, days to 50% flowering and days to first fruit set, Kashi Amrit was a good general combiner for number of primay branches/plant, CO-3 was a good general combiner for number of flower clusters/plant, number of flowers/cluster and number of fruits/plant, H-86 was a good general combiner for number of fruits/cluster, Fla 7171 was a good general combiner for fruit length, fruit width and fruit weight. Based on sca effects best specific combiner for plant height and fruit yield was Punjab Upma × Azad T-5. The ratio of σ2gca/σ2sca is less than unity for all characters except fruit shape index which also indicated the preponderance of non additive genetic variance. High heritability (>60%) combined with high genetic advance (>20%) was observed for fruit yield, number of primary branches/plant, plant height, number of flower clusters/plant, number of flowers/cluster, fruit weight, number of fruits/cluster, number of fruits/plant. These traits can be improved by simple selection in tomato breeding programme.
 Conclusion: From the study it was concluded that best general combiners for various yield and yield related traits were Pant T-3, Kashi Amrit, CO-3, H-86 and Fla 7171. Based on sca best specific combiner for plant height and fruit yield was Punjab Upma × Azad T-5.