Evaluation of tomato rootstocks to Ralstonia solanacearum and R. pseudosolanacearum in Mata mesoregion, PE

Géssyka R Albuquerque,Elineide B Souza,Júlio Carlos P Mesquita,Alessandro Nicoli,Marco Aurélio S Gama,Emanuel F Assunção,Adriano Márcio F Silva,Lucas P Lucena

doi:10.1590/s0102-0536-20210111

Abstract

ABSTRACT Bacterial wilt limits tomato production and resistant rootstocks could be important for the integrated management of the disease. Since there is an interaction between local bacterial strains and tomato genotype, this study aimed to evaluate 14 tomato rootstocks to bacterial wilt in the Mata mesoregion of Pernambuco state, Brazil. The rootstocks reaction to two sequevars of Ralstonia solanacearum and two of R. pseudosolanacearum was evaluated in four experiments carried out in the greenhouse using the completely randomized experimental design, with four replications composed of four plants each. Seven genotypes were selected to evaluate the reaction to bacterial wilt as rootstocks grafting in tomato plants ‘Tomini F1’ in a production area with disease history in the Chã Grande municipality, using randomized block design with four plants per treatment in each block. In the field experiment, disease symptoms were not observed in the grafted plants in ‘Guardião’, ‘Woodstock’, and ‘Yoshimatsu’. Regarding all experiments, ‘Guardião’ and ‘Muralha’ showed the best resistance levels and could be used in the integrated management of bacterial wilt and studied in plant breeding programs.

Highlights

The strains of the two species used in the greenhouse experiments were pathogenic and showed a high disease index (DI) (Table 1)
area under the disease progress curve (AUDPC) data transformed into resistance of the genotypes was specific for each strain, regardless of the species involved, in agreement with the results found in previous studies (Lebeau et al, 2011; Lopes et al, 2015; Kim et al, 2016)
The level of resistance of tomato rootstocks to bacterial wilt is highly related to environmental factors and the high genetic variability of Ralstonia species (Rivard et al, 2012; Santiago et al, 2017), especially in Brazil, which is considered an important center of genetic variability for those bacteria (Santiago et al, 2017)

Summary

Introduction

Tomato rootstocks reaction to bacterial wilt in an area with history of disease occurrence Based on the results with artificial inoculations in the greenhouse, the rootstocks ‘Guardião’, ‘Woodstock’, ‘Yoshimatsu’, ‘Tropithai’, ‘TD1’, and ‘Green Rise’ were selected and grafted with the hybrid genotype cv. Regarding R. solanacearum and the strain CRMRS91, for the variable DI, the least infected rootstocks were ‘Woodstock’ (47.5%), ‘Guardião’ (48.12%), ‘Muralha’ (58.12%), ‘Green Power’ (61.87%), and ‘BSPE0041’ (66.87%), that did not differ from ‘Hawaii 7996’ (36.87%), considered as a universal standard of resistance (Table 3).

Objectives

Results

Conclusion