Endophytic species of Colletotrichum associated with mango in northeastern Brazil

Abstract

Endophytic species of Colletotrichum associated with Mangifera indica (mango) are poorly understood. In this study, Colletotrichum species were isolated from mango in Pernambuco State, Brazil. There were significant differences in isolation frequencies of Colletotrichum species among sites and plant tissues. Mature leaf blades were colonized by most Colletotrichum isolates at the majority of sites. Partial sequences of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of 97 Colletotrichum isolates were amplified as an initial measure of genetic diversity. Phylogenetic analysis with a subset of 22 isolates were performed based on a multi-locus dataset (ACT, TUB2, CAL, CHS-1, GAPDH, ITS) followed by Apn2/MAT IGS sequence-analysis for isolates within the C. gloeosporioides species complex. Molecular analysis associated with phenotypic characteristics revealed six previously described species [C. asianum, C. cliviae, C. dianesei (syn. C. melanocaulon), C. fructicola, C. karstii and C. tropicale] and one new species. This new species is introduced as C. endomangiferae. All species isolated were pathogenic on mango fruits but varied in their virulence. There was no distribution pattern of species among sites and plant tissues, although C. asianum was the most prevalent species at all sites and in all plant tissues studied. Five previously reported Colletotrichum species causing anthracnose in mango fruits in northeastern Brazil were also recovered as endophytes.