Hybrid Vigor and Heritability Estimates in Tomato Crosses Involving Solanum lycopersicum × S. pimpinellifolium under Cool Tropical Monsoon Climate

Abstract

High humidity is a major constraint to increased tomato fruit production in a cool tropical monsoon climate. However, the genetic variation observed in Solanum pimpinellifolium makes it a good gene donor for breeding tomato cultivars capable of thriving under high humidity. The objective of this study was to estimate heterosis, heritability for higher yield, and to assess the adaptability of the genotypes to humid conditions. Genotypes were raised from five morphologically divergent parents, viz., wild parent (W)–“LA2093,” “CLN2498D” (D), “CLN2417H” (H), “Tima” (T), and “UC Dan INDIA” (U). The F1s were generated by biparental mating design using “LA2093” as a common pollen donor that was selfed to produce F2s and backcrossed to both parents to obtain BC1s and BC2s. The trial was laid out in a randomized complete block design with three replicates. Data were collected on selected yield-influencing traits and analyzed. “D × W” and “U × W” hybrids showed significant positive better parent heterosis for fruit weight per plant (30.4% and 35.5%) and total fruit yield (48.6% and 26.9%), respectively. The additive variance was higher than dominance variance for all the traits, including total fruit yield in all hybrids viz., “H × W,” “D × W,” “T × W,” and “U × W.” High narrow sense heritability estimate of ≥60% was observed in “D × W” and “U × W” hybrids for the majority of the floral and fruit traits including total fruit yield. This makes the improvement of “D × W” and “U × W” hybrids by direct selection advantageous. Hence, the adoption of selection for the affected traits in subsequent tomato breeding programs would enhance fruit yield and adaptability to humid environments.

Impact evaluation combining ability of tomato hybrids and lines for production and fruit quality traits

“…This implies that plant breeders can leverage the various general combining abilities of all parents to produce hybrids with specific and favorable combining effects in the desired direction. These results align with what was discovered by Ene et al (2023).…”

“…Using this approach can be helpful in finding genetic information that regulates the inheritance of traits being studied in early generations (Liu et al, 2021). It is the simplest way to understand how genetics influences inherited quantitative traits (Ene et al, 2023). Understanding how genes function makes it easier to decide whether to use heterosis breeding or recombination and selection (Singh et al, 2021).…”

Combining Image-Based Phenotyping and Multivariate Analysis to Estimate Fruit Fresh Weight in Segregation Lines of Lowland Tomatoes

“…The results of crossing M and K varieties have been analyzed in depth regarding traits that have the potential to be used as selection criteria [13,14]. In several studies, the significance of fruit weight stands out as a key determinant in shaping the direction of selection, closely aligned with considerations of overall productivity [14,[16][17][18][19]. Furthermore, in the hybridization of these two varieties, both the shape and weight of the fruit exhibit remarkable similarity [13,14].…”