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Mucoralesis an order of mostly saprobic fungi which includes broad host range plant pathogens. They are often associated with fruits, causing post-harvest deterioration and economic loss. In markets in the municipality of Recife, Pernambuco, Brazil, fruits with symptoms of soft rot and the presence of fungi with the appearance of Mucoraleshave been observed. Sporangiophores bearing black and globose sporangia were visualized on the surface of the rotten tissues. Isolates obtained from symptomatic tissues were cultured in potato dextrose agar culture medium, and cultural and microscopic observations were performed. According to the morphological characteristics, the isolates were identified as Gilbertella persicariaand their identity was confirmed by phylogenetic analyses of the ITS and LSU rDNA regions. Gilbertella persicaria, the unique species of the genus, is commonly found in soil, water, dung and often isolated from fruit with post-harvest soft rot. In the present study, nine isolates were obtained and identified, five from acerola, two from cashew, one from papaya and breadfruit. To our knowledge, this is the first report of G. persicariacausing acerola and papaya rot in Brazil and the first report of the species as a cashew and breadfruit pathogen in the world.

The sweet potato (Ipomoea batatas(L.) Lam) is a common crop species in Brazil. Factors limiting its cultivation include root rot. Sweet potato roots showing rot symptoms were collected from the state of Pernambuco in Northeastern Brazil. Soft necrotic lesions along the roots, with the presence of white mycelium under the lesions and a strong odor were noted. Seven fungal isolates were obtained which showed white mycelia with hyphae fragmenting into arthroconidia. To determine the identity of the fungi, DNA was extracted and used in PCR reactions. PCR products were sequenced from the gene regions D1/D2 in 26S rRNA and compared to sequences in GenBank using BLASTn. Based on molecular results and phylogenetic analyses, the fungi were identified as Geotrichum candidum. Pathogenicity tests were performed which confirmed Koch's postulates. This study represents the first report of Geotrichum candidumcausing sweet potato sour rot in Brazil.