Indução de resistência ao nematóide das galhas (Meloidogyne spp.) em tomateiro por rizobactérias

• Ano de defesa: 2006
• Autor(a) principal: Fabry, Cléia de Fátima Silva
• Orientador(a): Freitas, Leandro Grassi de
• Banca de defesa: Ferraz, Silamar , Alfenas, Acelino Couto , Costa, Maurício Dutra , Paula Júnior, Trazilbo José de
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Fitopatologia
• Departamento: Etiologia; Epidemiologia; Controle
• País: BR
• Palavras-chave em Português: Controle biológico; Rizobactérias; Nematóides
• Palavras-chave em Inglês: Biological control; Rhizobacteria; Nematode
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::FITOPATOLOGIA
• Link de acesso: http://locus.ufv.br/handle/123456789/1074

Root-knot nematode, Meloidogyne spp., is responsible for great losses in agricultural production. Non-pathogenic bacteria inhabitants of the rhizosphere or rhizoplan, known as rhizobacteria, have shown a great potential for controlling phytonematodes. Thus, the objectives of this work were: to evaluate the induction of resistance in tomato against Meloidoyne javanica mediated by Rhizobium etli; verify the biocontrol potential of R. etli against M. javanica and M. incognita in different pathogen inoculum densities in tomato; verify the potentialization of R. etli through addition of humus to the soil for the biocontrol of M. javanica and M. incognita; and test isolates with proven antagonistic efficiency against other phytopathogens for the control of M. javanica and M. incognita in tomato. Rhizobacteria R. etli G12 induced systemic resistance against M. javanica in tomato grown in split-root system, having the number of gals and eggs per root system reduced in 35.3% and 38.8% respectively, but there was no plant growth promotion in the studied conditions. In the experiments with earthworm humus application to the soil, at concentrations 0, 50 and 150 g/1.5 kg of soil in the assay with M. incognita, and 0, 50, 100, 150 and 200g in the assay with M. javanica, increase in the antagonistic activity of R. etli occurred for both nematodes, however, the use of humus without the application of rhizobacteria did not result in nematode control. Rhizobium etli G12 in presence of humus promoted plant growth, resulting in increase in green biomass weight and plant height. Bacterium R. etli was efficient in reducing the number of gals and eggs of M. javanica and M. incognita in both low and high concentrations of nematode inoculum (2,000 and 4,000 eggs). The 27 isolates of tested rhizobacteria were efficient in controlling M. javanica and M. incognita when applied in seed microbiolization, but it did not control nematodes when applied as plant irrigation with cell suspension.