Extratos de Stryphnodendron adstringens e Caesalpinia ferrea no controle de bacterioses do tomateiro

• Autor(a) principal: Cavalcante, Gilcianny Pignata
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1061
• topic: Enzimas; Taninos; Controle alternativo; indução de resistência; Enzymes; Tannins; Alternative control; Inducing resistance; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::FITOPATOLOGIA

Antimicrobial activity of extracts of Stryphnodendron adstringens bark and Caesalpinia ferrea fruits were investigated against bacteria Pseudomonas syringae pv. tomato, Ralstonia solanacearum and Clavibacter michiganensis subsp. michiganensis. The fractions C. ferrea extracts in ethyl acetate and n-butanol showed greater activity against all three bacterias. The Minimum Inhibitory Concentration (MIC) was equal to 0.32 and 1.3 mg/ml against the bacteria R. solanacearum, conferred by fractions of C. ferrea in ethyl acetate and n-butanol respectively. For the bacteria P. syringae pv. tomato, the MIC was equal to 0.65 mg/mL in both ethyl acetate and n-butanol C. ferrea fractions. For the Gram positive bacteria, C. michiganensis subsp. michiganensis, the MIC was equal to 1.3 mg/mL conferred by the same C. ferrea fractions. According to the results of bioautography, the bacteria C. michiganensis subsp. michiganensis had their growth inhibited by fractions of C. ferrea and S. adstringens in ethyl acetate. The bacteria R. solanacearum was inhibited by fractions of C. ferrea and S. adstringens in ethyl acetate and the C.ferrea fraction in n-butanol. The bacteria P. syringae pv. tomato was inhibited by the fractions of two plants in ethyl acetate and n-butanol. Phytochemical analysis of the active fractions revealed the presence of saponins and tannins, and the activity was conferred by tannins, evidenced by the inhibition zone. The fractions were also investigated against bacterial wilt and bacterial canker of tomato. There was not a reduction in the incidence of bacterial wilt, but the bacterial canker of tomato was controlled. Plants treated with C. ferrea fractions in ethyl acetate, n-butanol and aqueous showed reduction or absence of disease symptoms. The fractions were also evaluated for severity reduction of bacterial speck of tomato. In the first experiment there was a reduction in disease severity in 96.5, 81.7 and 80.1% on treatments with acibenzolar-S-methyl (ASM), fraction of S. adstringens in ethyl acetate and n-butanol, respectively. In the second experiment, there was a reduction in disease severity in 71, 50.8 and 46.9% in plants treated with the fraction of S. adstringens in ethyl acetate, followed by ASM and C. ferrea fraction in n-butanol. The fraction of S. adstringens in ethyl acetate and ASM were evaluated for defense enzyme activity against bacterial speck. According to the results, at certain times of assessment, there was an increase in the activity of peroxidase, polyphenol oxidase, β-1,3-glucanase and phenylalanine ammonia lyase in plants treated with ASM and the fraction of S. adstringens in ethyl acetate, increasing defense response primarily on the treated and inoculated plants with bacteria.