Assessment of morphological and molecular diversity in tomato accessions using quantitative traits and RAPD markers

Abstract

This study used quantitative characteristics and RAPD markers to examine the molecular and morphological diversity of 19 tomato accessions. Significant variability was observed in key morphological traits, including plant height (98.3–143.3 cm), days to 50% flowering (50.1–62.9 days), number of fruits per plant (28.3–317.6), and fruit weight (31.6–115 g). The highest variability was found in the number of fruits per plant, followed by plant height and fruit weight, suggesting substantial genetic diversity within the accessions. Based on morphological data, a dendrogram created with NTSYS-pc software categorized the accessions into five different groups with the highest genetic dissimilarity (99.4%) observed between DVRT-2 and PB-UPMA, demonstrating a high level of genetic diversity. The genetic dissimilarity matrix based on these traits showed a wide range of variation, with coefficients ranging from 0.019 to 0.994 with the highest dissimilarity observed between DVRT-2 and PB-UPMA. Twenty RAPD primers were used in molecular characterisation, producing 129 bands, 96 of which were polymorphic, indicating an average polymorphism of 72.63%. Out of the 20 RAPD markers, 19 were polymorphic, while OPA-03 was the least polymorphic, with low polymorphism of 25%. Significant genetic variety across the tomato accessions was highlighted by the 72.63% total polymorphism found across all markers. According to RAPD analysis, PDT-3-1-1 and PB Keshri have the highest similarity (91.5%). The combined morphological and molecular analyses provide valuable insights into the genetic diversity of tomato germplasm, which can aid in selecting superior genotypes for breeding programs. The study underscores the importance of integrating both morphological and molecular markers in tomato breeding to enhance genetic improvement and cultivar development.