RESUMO
ABSTRACT Anthracnose is a crop disease usually caused by fungi in the genus Colletotrichum or Gloeosporium. These are considered one of the main pathogens, causing significant economic losses, such as in peppers and guarana. The current forms of control include the use of resistant cultivars, sanitary pruning and fungicides. However, even with the use of some methods of controlling these cultures, the crops are not free of anthracnose. Additionally, excessive application of fungicides increases the resistance of pathogens to agrochemicals and cause harm to human health and the environment. In order to find natural antifungal agents against guarana anthracnose, endophytic fungi were isolated from Amazon guarana. The compounds piliformic acid and cytochalasin D were isolated by chromatographic techniques from two Xylaria spp., guided by assays with Colletotrichum gloeosporioides. The isolated compounds were identified by spectrometric techniques, as NMR and mass spectrometry. This is the first report that piliformic acid and cytochalasin D have antifungal activity against C. gloeosporioides with MIC 2.92 and 2.46 µmol mL-1 respectively. Captan and difenoconazole were included as positive controls (MIC 16.63 and 0.02 µmol mL-1, respectively). Thus, Xylaria species presented a biotechnological potential and production of different active compounds which might be promising against anthracnose disease.
Assuntos
Doenças das Plantas/prevenção & controle , Xylariales/química , Paullinia/microbiologia , Endófitos/química , Fungicidas Industriais/farmacologia , Filogenia , Doenças das Plantas/microbiologia , Espectrometria de Massas , Xylariales/isolamento & purificação , Xylariales/genética , Xylariales/metabolismo , Estrutura Molecular , Colletotrichum/efeitos dos fármacos , Colletotrichum/fisiologia , Endófitos/isolamento & purificação , Endófitos/genética , Endófitos/metabolismo , Fungicidas Industriais/isolamento & purificação , Fungicidas Industriais/químicaRESUMO
Podosordaria mexicana Ellis & Holway é pela primeira vez citada para o Brasil. Trata-se de um fungo da familia Xylariaceae comumente encontrado sobre fezes de burro, coelho, vaca e cavalo. Esta espécie se distingue das demais pelo estroma obcónico e curto-estipitado e pelo tamanho dos seus ascosporos. As outras espécies curto-estipitadas possuem ascosporos pequenos. Os espécimens estudados estäo depositados no Herbário do Departamento de Micología da Universidade Federal de Pernambuco (URM) sob n§ 73600 e 74489 respectivamente, coletadas no município de Agrestina - PE, no ano de 1977