Analysis of Genetic Variability, Heritability, and Genetic Advance for Yield-Associated Traits under High Temperature Stress in Tomato (Solanum lycopersicum L.)

The objective of this study was to examine the genetic variability, heritability, and genetic advancement in tomato plants (both parents and hybrids) in terms of their tolerance to high temperatures. The research was conducted at the ICAR-Indian Institute of Vegetable Research (ICAR-IIVR) in Varanasi during the summer season of 2024 (February-May). In this study, a total of 23 tomato genotypes comprising 8 parent varieties and 15 hybrid crosses were cultivated using a completely randomized block design (CRBD). The ANOVA analysis indicated a notable level of genetic variability present in the genotypes for the traits under investigation. Both the phenotypic and genotypic coefficient of variation showed a higher PCV for all traits examined in relation to their respective GCV, highlighting the significant impact of environmental factors on the results. Significant heritability and genetic advance were noted for various traits, including average fruit weight, fruit quantity per plant, fruit setting, plant yield, anther tip burning, plant height, seed count per fruit, stigma exertion, crop duration, and pollen viability, underscoring their potential for genetic improvement in future research endeavors. Our research findings indicate that these characters are influenced by the cumulative effects of genes, highlighting the potential effectiveness of employing a selection method to enhance their tolerance to high temperatures in tomato plants.