Aspectos do antagonismo de bactérias endofíticas a Meloidogyne incognita em tomateiro

• Ano de defesa: 2008
• Autor(a) principal: Pinho, Renata Silva Canuto de
• Orientador(a): Campos, Vicente Paulo
• Banca de defesa: Souza, Ricardo Magela de, Oliveira, Denilson Ferreira de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Lavras; Escola de Ciências Agrárias de Lavras (ESAL)
• Programa de Pós-Graduação: Programa de Pós-Graduação em Agronomia/Fitopatologia
• Departamento: Departamento de Fitopatologia
• País: BRASIL
• Palavras-chave em Português: Meloidogyne incognita; Bactérias endofíticas; Controle biológico; Biological control; Endophytic bacteria
• Área do conhecimento CNPq: Ciências Agrárias
• Link de acesso: https://repositorio.ufla.br/handle/1/2963

The effect of Acinobacter johnsonii on the oriented migration of second stage juveniles (J2) of Meloidogyne incognita toward tomato roots and on the J2 storage, simultaneouly, or not with A. johnsonii was studied. It was, also, studied the effect of several endophytic bacterium isolates on the damage and reproduction of M. incognita, as well as the relationship of those antagonisms to tomato root colonization. Any A. johnsonii isolates added to the substract reduced the J2 migration. However, the parasitism and reproduction of M. incognita were always lower when bacterium inoculum was poured at 8 cm from the circle center. During J2 storage period with or not A. johnsonii, the reproduction and infectivity of J2 decreased progressively indicating that this bacterium was not pathogenic to M. incognita and that the major factor, in this environment, was the progressive decrease on the J2 body energy by erratic J2 movement. Migration experiment better characterized the antagonism of A. johnsonii to M. incognita compared to storage experiment. From 39 endophytic bacterial isolates tested, fifteen of them reduced, simultaneously, gall, egg-masses and eggs per gram of roots, but, only, three of them did not colonized tomato roots corresponding 80% the relationship between control and root colonization. This relationship increased to 85% when considered, separately, the three measurements of control efficacy. The species that gave better control of M. incognita were: Acinobacter johnsonii (T 9 e T10), Curtobacterium luteum (P 16), Bacillus pumillus subg. B (T 27), B. pumillus (T 26) e B. amyloliquefaciens (T 36) which colonized, also, the tomato roots. A. jonhsonii (T 10), S. aureus (P 18), P. gordonae (T 47), B. pumillus (T 51) and isolate P 11 (unidentified species) reduced, also, the disease severity caused Pseudomoas syringae pv. tomato in tomato according to Silva (2004). The root colonization test should precede every bacterial screening for antagonism to plant parasitic nematodes.