Genetic variability for selected tomato (Lycopersicon esculentum Mill.) varieties in the forest–Savanna transition zone of Ekpoma, Edo State, Nigeria

Abstract

A study was conducted at the Teaching and Research Farm of Ambrose Alli University, Ekpoma, to evaluate the genetic variability of four tomato (Lycopersicum esculentum) varieties. The experiment employed a Randomized Complete Block Design (RCBD) with four replicates and focused on both vegetative and yield-related traits. Among the tested varieties, Superstar consistently outperformed others in plant height, number of leaves, leaf area, stem girth, and branching across 2, 4, 6, and 8 weeks after planting (WAP). High heritability estimates coupled with substantial genetic gain for traits such as plant height, leaf number, and stem girth suggest strong additive gene effects, indicating that these traits are highly amenable to selection in breeding programs. For instance, plant height recorded heritability values of 90.22% and 95.95% at 2 and 4 WAP, with corresponding genetic gains of 11.90 and 6.48. In contrast, traits like leaf area exhibited low genetic gain at later stages (0.41–2.21), reflecting non-additive gene action. Superstar also demonstrated superior yield potential and early flowering, making it particularly suitable for cultivation under Ekpoma conditions. Based on these findings, the study recommends Superstar as a promising candidate for local tomato improvement programs aimed at enhancing productivity and adaptability in the region.