Inheritance of resistance to Ralstonia pseudosolanacerum in tomato genotypes Yoshimatsu and Hawaii 7996

Abstract

Among the various diseases that affect tomato crops, bacterial wilt stands out due to its high level of damage during the cycle and the difficulty of controlling it. Among the control strategies is the use of resistant cultivars. However, in order to obtain these cultivars, resistance inheritance studies are an essential step. With this in mind, the aim of this work was to study the inheritance of resistance to Ralstonia pseudosolanacearum in the tomato genotypes Yoshimatsu and Hawaii 7996 and to determine whether the resistance loci that govern the trait in these materials are the same. The Yoshimatsu and Hawaii 7996 genotypes and the F₁, F₂, BC₁₁ and BC₂₁ generations were evaluated in one experiment and 60 F_2:3 progenies in a second experiment. The severity of bacterial wilt was assessed using a descriptive scale of scores at 20 days after inoculation. In the Yoshimatsu genotype, the inheritance of resistance to Ralstonia pseudosolanacearum is governed by two major effect genes in recessive homozygosity. In the Hawaii 7996 genotype, the inheritance of Ralstonia psedosolanacearum resistance is governed by a gene with partial dominance action. The greatest contribution of gene effects was due to additive variance. For Ralstonia psedosolanacearum it is recommended to select 20 days after inoculation between and within F_2:3 progenies.