Genetic parameters of resistance components to Xanthomonas spp. in tomato
Marcelo Francisco Mendes de Souza, Rosana Rodrigues, Antonio Teixeira do Amaral Júnior and Cláudia Pombo Sudré
Abstract: This study aimed to estimate genetic parameters of tomato for reaction to bacterial spot in six parents and fifteen hybrids to identify resistant genotypes and indicate breeding programs for satisfactory genetic gains. The genotypes were evaluated in a complete randomized block design with three replications and six plants per plot in a greenhouse. The resistance to bacterial spot was evaluated on three bases: on a grade scale (GS), based on the area under the diseaseprogress curve (AUDPC) and on the incubation period (IPR) of the races TI, T2 and T3, at 10° CFU mL*!, UENF 157 was resistant to races TI, T2 and T3 and UENF 158 to race T2. The bulk method can be recommended for better results in recombined inbred lines for Tl-resistance, while the pedigree method is proposefdor T2 and T3.