STUDIES ON INHERITANCE OF BACTERIAL WILT RESISTANCE IN TOMATO CROP CAUSED BY Ralstonia solanacearum (E.F. SMITH)

Abstract

The study aimed at the inheritance of bacterial wilt resistance in tomato with six different generations (P1, P2, F1, F2, BC1 and BC2) obtained by 4 crosses (Susceptible X Resistant). Two susceptible cultivars (Arka Meghali and Arka Vikas) and two resistant lines (H-7996 and H-7997) of tomato were crossed during kharif , 2020 in four possible combinations to generate the experimental material. The P1, P2, F1, F2 BC1 and BC2 generations of 4 crosses were screened for bacterial wilt caused by Ralstonia solanacearum (E.F. Smith) in tomato research fields of Monsanto Holdings Private Ltd., Kallinayakana Halli village, Gauribidanuru Taluka, Chikkaballapura District, Karnataka to understand the mode of inheritance. Single dominant gene controlling the resistance to bacterial wilt was observed in two crosses between Arka Meghali x H-7996 and Arka Vikas x H- 7997. Chi-square test for goodness of fit indicated that the F2 is segregating in the ratio 3 resistant to 1 susceptible in the single gene model. Resistant to susceptible ratio in BC2 was 1:1. While, in the crosses between Arka Vikas x H-7996 and Arka Meghali x H-7997 the complimentary gene interaction was observed with the F2 expected ratio of 9:7 indicating duplicate recessive epistasis.