Identification of Lines of Tomato Resistant to Bacterial Wilt

Abstract

The objective of this study was identifying lines of tomato plants resistant to the bacterial wilt. The work was accomplished was developed in the Laboratory of Bacteriology and in the greenhouse at Department of Agronomy of Federal Rural University of Pernambuco, during the months of August and September 2016. The experiment design was completely randomized in the factorial 30x3 with three repetitions. The treatments consisted of 30 genotypes submitted to three Ralstonia solanacearum isolates. The components were consistent after inoculation, in which the incidence of the disease was quantified. The data were submitted to analysis of variance and the averages were grouped by the Scott-Knott test at 5% probability, they were still obtained phenotypic, genotypic and environmental correlations and dendrogram of dissimilarity. Considering the bacterial wilt index, eight lines were classified as resistant. It was possible to observe high phenotypic, genotypic and environmental correlation coefficients between resistance components, demonstrating that the resistance and susceptibility characteristics are genetic and influenced by environmental conditions.  It was observed through dissimilarity the formation of four groups and four subgroups, in which the “I” group was composed of four witnesses of resistance, which was resistant and moderately resistant strains. It was possible to observe that the results indicate that eight lines can be used in crosses to obtain hybrids resistant to bacterial wilt. The latency period can use as a reference in the selection of materials with resistance to Ralstonia pseudosolanacearum. The lineages that stood out for resistance to bacterial wilt were: L04, L42, L49, L53, L82, L120, L125 and L128.