Genetic Parameters, Diversity and Population Structure in Tomato based on Quantitative Traits and Microsatellite Markers

Fifty accessions of tomato, including related species were evaluated to study genetics for yield and quality attributes and diversity based on quantitative traits and molecular markers. The results have shown high heritability and genetic advance for the number of fruits per plant (96.14 and 193.5), fruit weight (87.61 and 96.70), yield per plant (95.45 and 78.90) and lycopene content (98.31and 43.44) which indicated that these traits based selection is adequate. Among the accessions, extensive genetic diversity was observed for both quantitative traits and molecular analysis. From cluster means, accession Khasi Local was superior for fruit weight (80.30 g), LE-1-2 for lycopene (12.23 mg/100g) and S. peruvianum (1) for TSS (6.17) and vitamin-C (46.63mg/100g) content. In molecular analysis (35 microsatellite markers), a total of 118 alleles were observed with an average of 3.47 alleles per marker, and polymorphism information content ranged from 0.25 (SLM6-38) to 0.79 (LEat-015). From group based genetic diversity analyses, maximum diversity was observed in common cultivated tomato (100%) followed by cherry tomato (82.35%) and local landraces (Khasi Local and Tura-1). The molecular markers associated to QTLs for tolerance to bacterial wilt (SLM6-17, SLM6-14), fruit firmness (LEga7, LEaat7, and LEaat1), shelf life (LEat16) and yield (LEaat1 and LEaat18) have also shown wider diversity. Moreover, marker SLM6-17(150bp) tightly linked to major QTL associated with bacterial wilt was unique to accession LE-1-2, DMT-1 and BWT-3 and SLM-6-14 (240bp) for Sel-3, BWT-3, and RCT-3. These markers could be utilized in the selection of genotype having multiple desirable traits through MAS approaches.