Studies of heterosis and inbreeding depression for growth parameters in tomato hybrids (Solanum lycopersicum L)

Abstract

The experimental material consisted of 13 genotypes, including 10 lines, 3 testers, and one standard check (Pant T1). These genotypes were chosen based on their performance for various traits. A Line Tester design was used to evolve 30 F1s and 30 F2s from these 13 genotypes. An investigation was conducted on the three growth parameters, specifically Days to 50% flowering, plant height, and number of primary branches per plant, to examine heterosis and inbreeding depression. The cross VRT-18×H-86 exhibited the highest significant negative mid-parent, better parent, and standard heterosis for days to 50% flowering, which is advantageous in terms of early flowering. Additionally, it displayed the lowest level of inbreeding depression. The cross VRT-51×SEL-7 exhibited the highest level of heterosis in terms of plant height, with a significant magnitude of 44.50%. On the other hand, the cross H-24×SEL-7 displayed the lowest level of inbreeding depression, with a magnitude of 17.48%. When examining the number of primary branches per plant, we found that Kashi Aman×SEL-7 exhibited the highest level of heterosis at 48.40%. On the other hand, the cross VRT-01×ToLcv-41 showed the lowest level of inbreeding depression at -35.35%, which is quite desirable. These findings suggest that these specific crosses have the potential for further selection in varietal development programmes.