IDENTIFICAÇÃO MORFOLÓGICA E MOLECULAR DE Curvularia sp. AGENTE CAUSAL DA MANCHA FOLIAR DO MILHO

RESUMO - Fungos do genero Curvularia sao amplamente distribuidos ao redor do mundo, podendo estar associados a especies vegetais, na forma saprofitica, endofitica ou como parasita. Especies do referido genero sao responsaveis por diversas doencas em plantas cultivadas, causando principalmente manchas foliares. A correta identificacao das especies e importante para o conhecimento e manejo das doencas, sendo essas identificacoes baseadas principalmente em caracteristicas morfologicas, como aspectos dos micelios, morfologia das hifas, formas e tamanho dos conidios. Entretanto, tecnicas moleculares como a amplificacao de genes especificos, alem de analises do padrao de digestao de regioes ITS atraves de enzimas de restricao, tem contribuido para a identificacao e diferenciacao genetica entre especies. No presente trabalho foi realizada a caracterizacao morfologica e molecular de isolados de Curvularia oriundos de plantas de milho infectadas. Os isolados foram agrupados de acordo com a identificacao morfologica e molecular, sendo que todos apresentaram o mesmo perfil de amplificacao do DNA. As tecnicas morfologicas e moleculares possibilitaram a caracterizacao de uma unica especie, Curvularia lunata. Palavras–chave: Zea mays L., Curvularia lunata, morfologia, DNA, perfil de restricao. MORPHOLOGICAL AND MOLECULAR IDENTIFICATION OF Curvularia sp.CAUSAL AGENT OF CORN LEAF STAIN ABSTRACT - Fungi of the genus Curvularia are widely distributed around the world and may be associated with plant species, in the saprophytic, endophytic or parasitic form. Species of this genus are responsible for several diseases in cultivated plants, causing mainly foliar stains. The correct identification of the species is important for the diseases knowledge and management, being these identifications based mainly on morphological characteristics as aspects of the mycelia, conidia forms and size, hyphae morphology. However, molecular techniques such as the amplification of specific genes, as well as digestion pattern analyzes of ITS regions through restriction enzymes, have contributed to the identification and genetic differentiation between species. In the present study, the morphological and molecular characterizations of Curvularia isolates from infected corn plants were realized. The isolates were grouped according to the morphological and molecular identification, all of which presented the same DNA amplification profile. Morphological and molecular techniques allowed the characterization of a single species, Curvularia lunata.  Keywords: Zea mays L. Curvularia lunata, morphology, DNA, restriction profile.