UNRAVELLING FRUIT TRAIT DIVERSITY AND BREEDING POTENTIAL IN TOMATO VARITOME ASSOCIATION PANEL ACROSS TWO SEASONS

Abstract

Genetic variability in tomato germplasm provides opportunities to identify accessions for the improvement of fruit morphology, quality and productivity. This study assessed variability and selection potential for ten flowering, fruit and yield traits in 137 accessions of the tomato Varitome collection, comprising 25 Solanum pimpinellifolium, 93 S. lycopersicum var. cerasiforme and 19 S. lycopersicum var. lycopersicum accessions, during Summer 2025 and Rabi 2025–26 at ICAR–NISST Regional Station, Bengaluru, India. Each season was laid out in an augmented randomized complete block design with four blocks and six replicated checks, and analysed separately. Test accessions differed significantly for all traits in both seasons, except fruit yield per plant in Rabi. Average fruit weight ranged from 1.11 to 146.91 g in Summer and from 1.18 to 149.78 g in Rabi (means 26.00 ± 3.15 and 26.83 ± 3.21 g) and recorded the highest genotypic coefficient of variation (124.99 and 123.27%) with high broad-sense heritability (97.78 and 94.14%). Locule number, fruit equatorial diameter and fruit height combined high genotypic variability with heritability above 90% and high genetic advance as per cent of mean in both seasons. Total soluble solids averaged 6.80 and 6.85 °Brix, with heritability of 91.71 and 92.06%. Heritability of fruit yield per plant declined from 68.26% in Summer to 47.34% in Rabi, indicating weaker support for phenotypic selection for yield in the latter season. Fruit weight, locule number, fruit dimensions and soluble solids are therefore effective criteria for preliminary selection within the panel. Because broad-sense heritability does not partition additive genetic variance and the seasons were analysed separately, selected accessions require replicated multi-environment evaluation to confirm their stability and breeding value.