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Phytopathogenic fungi during the penetration and colonization process are capable of secreting several enzymes, which enable infection of the host live tissue, acting on the degradation of wax, cuticle and cell walls. The ability of a pathogenic agent to produce enzymes or not can determine the severity degree of a disease. In this study, 33 isolates of Colletotrichum gloeosporioides related to anthracnose and blister spot on coffee trees were evaluated for their ability to produce hydrolytic enzymes (amylase, lipase, protease, laccase, pectinase and cellulase) and specific cell wall degrading enzymes “CWDEs” (polygalacturonase, polymethylgalacturonase and pectin-lyase), as well as their relationship with the pathogenicity/aggressiveness of isolates. For all isolates of C. gloeosporioides, extracellular enzymes could be detected, except cellulases. Isolates I-9 and I-24 produced the highest levels of extracellular enzymes, as well as CWDEs. They also had the highest disease intensity indexes, suggesting a relationship between enzymes and aggressiveness of the isolates. RESUMO Fungos fitopatogênicos durante o processo de penetração e colonização são capazes de secretar uma variedade de enzimas, as quais os tornam capazes de infectar o tecido vivo do hospedeiro, atuando na degradação de ceras, cutícula e das paredes celulares. A capacidade de um agente patogênico em produzir ou não enzimas pode determinar o grau de severidade da doença. Foram avaliados 33 isolados de Colletotrichum gloeosporioides relacionados à antracnose e mancha manteigosa do cafeeiro, quanto a sua capacidade de produção de enzimas hidrolíticas (amilase, lipase, protease, lacase, pectinase e celulase) e enzimas específicas degradadoras da parede celular “EDPC” (poligalacturonase, polimetilgalacturonase e pectinaliase), e sua relação com a patogenicidade/agressividade dos isolados. Para todos os isolados de C. gloeosporioides foi possível a detecção de enzimas extracelulares, com exceção de celulases. Os isolados I-9 e I-24 apresentaram os maiores índices de produção de enzimas extracelulares, e assim como de EDPCs. Os mesmos obtiveram os maiores índices de intensidade de doença, sugerindo a relação entre estas e a agressividade dos isolados.

In Brazil, Colletotrichum gloeosporioides is associated with a complex of symptoms in coffee culture. Although this pathogen had its pathogenesis observed and identified, its importance has still been questioned due to its several endophytic forms, raising doubts as to the real importance of the pathosystem. The aim of this study was to demonstrate, by using an isolate transformed with the gene gfp, the infection and colonization capability of C. gloeosporioides in coffee seedlings. After the fourth day of inoculation, manifestation of symptoms as punctual necrosis could be observed, which progressed during the evaluation period, culminating in the death of seedlings. Epifluorescence microscopy confirmed the presence of the pathogen in the seedlings, as well as the visualization of internal colonization of tissues, acervulus formation and conidium production, confirming that it was responsible for the observed symptoms.