Silício na resistência da bananeira ao mal do Panamá

• Ano de defesa: 2009
• Autor(a) principal: Fortunato, Alessandro Antônio
• Orientador(a): Rodrigues, Fabrício de ávila
• Banca de defesa: Silva, Ivanete Tonole da , Mizubuti, Eduardo Seiti Gomide
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Fitopatologia
• Departamento: Etiologia; Epidemiologia; Controle
• País: BR
• Palavras-chave em Português: Silício; Bananeira; Mal do Panamá
• Palavras-chave em Inglês: Silicon; Banana; Panamá disease
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::FITOPATOLOGIA
• Link de acesso: http://locus.ufv.br/handle/123456789/4416

This study aimed to determine the effect of silicon (Si) to reduce the symptoms of Panamá disease, caused by Fusarium oxysporum f.sp. cubense (Foc), on banana, besides the potentialization of some biochemical mechanisms of defense. Plants from cultivars Grande Naine (resistant) and Maçã (susceptible), were grown on plastic pots amended with 0 (-Si) and 0.39 g Si (+Si) per kg of soil and inoculated with Foc at 60 days after transplanting. Panamá disease progress (indirect and direct evaluations) and some biochemical determinations were performed. There was no difference between cultivars for Si concentration on the root system and on the rhizome-pseudostem, but Si concentration was higher on plants supplied with Si than on plants non-supplied with this element. Plants from cultivar Maçã showed the highest Si concentration on the pseudostem as compared to plants from cultivar Grande Naine . Calcium concentration on the root system and on the rhizomepseudostem was similar between plants from the two cultivars. The values for the variables area under reflex symptoms progress curve on leaves, area under symptoms progress on root system progress curve, and area under dark pseudostem progress curve were reduced in the presence of Si. Plants supplied with Si from both cultivars also showed reduced values for area under asymptomatic fungic colonization progress curve, area under relative lesion length progress curve, and area under Panamá disease progress curve. The concentration of pigments on leaves from the two cultivars supplied with Si was greater as compared to plants non supplied with this element. The concentration of malonic aldehyde and hydrogen peroxide was not different between the two cultivars supplied or not with Si. The concentration of total soluble phenolics and lignin-thioglycolic acid derivatives was greater on root system of plants from the two cultivars supplied with Si. The activities of the enzymes phenylalanine ammonia lyase, peroxidase, polyphenoloxidase, glucanase, and chitinase on the root system of the two cultivars were not potentiated by Si. The results of this study show an effect of Si to potentiate defense responses of banana to Foc, especially for the susceptible cultivar through the reduction of disease symptoms in association with a greater lignification and production of phenolics on the root system.