Combining ability and genetic analysis of fruit and leaf yield in gboma eggplant
Gboma eggplant (Solanum macrocapon L.) of the family Solanaceae is an important fruit and leafy indigenous vegetable in Africa. Despite the numerous nutritional, medicinal and economic benefits derived from the crop, little is known about the genetic parameters governing the inheritance and combining ability of the yield components. Thus, a study was conducted to investigate genetic information on the relevant yield components of the crop. Results showed significant mean squares for General Combining Ability, Specific Combining Ability effects for number of leaves per plant, fruit width and plant height, indicating the combining effect of additive, non-additive and maternal effects for expression for those traits. Conversely, significant (P< 0.05) SCA effects for number of branches per plant, leaf length, leaf width and fresh leaf weight indicated the preponderance of non-additive gene effect. GCA/SCA ratios for the various traits indicated that the relative contribution of additive to non-additive effects varied widely from trait to trait. Significant reciprocal effects for most of the traits were an indication that cytoplasmic or maternal gene effects played a major role in modifying the inheritance of the yield parameters, and that the choice of the maternal parent is relevant in breeding for these traits. Estimated GCA effect among the parents revealed that CAGRIC 03 has a breeding value for number of branches, plant height, fruit length, leaf length and fresh leaf weight, which makes it a valuable material for development of improved varieties. CAGRIC 01 was the promising combiner to increase fruit weight and number of leaves per plant. Hybrid P1xP2 was the best specific combiner to increase fruit width, leaf width and fruit width. High heritability estimates for most of the traits indicate that genetic variation was higher than the environmental variation in the study.
Keywords: African eggplant, heritability, Solanum macrocapon