Richness of Nigrospora spp. (Apiosporaceae) in Manihot esculenta in Brazil and the description of three new species

Manihot esculenta, commonly known as cassava, is an important staple food in developing countries in Africa, Asia and Latin America. Despite its relevance, few surveys of endophytic fungi have been carried out on this plant. Nigrospora spp. have a wide range of hosts and can be found as saprobes, endophytes, and pathogens. Nigrospora has already been isolated from cassava plants in previous studies. However, its identification was made only at the genus level. In this study, healthy cassava stems were collected in the northeast region of Brazil from where specimens of this genus were obtained. The isolates were identified based on morphological features and phylogenetic analyses of internal transcribed spacer (ITS), part of the translation elongation factor 1 alpha (TEF1- α), and β-tubulin fragment (TUB2) genic regions. As a result, we report two new geographic occurrences of N. pyriformis, and N. vesicularifera, four new records of N. hainanensis, N. lacticolonia, N. pyriformis, and N. vesicularifera associated with cassava, and the description of three new species named N. endophytica, N. manihoticola and N. pernambucoensis.