Citation | Open Access. In the last years, several apple varieties have been well-adapted to grow under the tropical conditions of northeastern Brazil. However, fungal diseases can be a limiting growing factor under these conditions. Cankers, dieback, and eventual plant death were observed in 2-year-old apple trees, cultivar Eva, in Paraipaba county, State of Ceará, Brazil, in 2015. In an attempt to identify the causal agent, symptomatic tissue from the trunk was collected and disinfected in

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... alcohol and 1.5% sodium hypochlorite. Tissue was plated onto potato carrot agar (PCA) and incubated at approximately 25°C for 7 days. Fungal colonies developed from infected tissue were dark or grayish. Hyphal tips were plated again in PCA medium with sterilized pine needles and incubated for 10 to 15 days to produce pycnidia and sporulation. Conidia were ellipsoid to ovoid and measured 22.83 µm long and 11.58 µm wide (n = 140). Conidia were hyaline when immature and brown with a central transverse septum and longitudinal striations when mature. These characteristics indicated that this species is morphologically similar to those in the genus Lasiodiplodia (Netto et al. 2014). A monosporic culture grown in PCA medium was used for DNA extraction. To confirm identification, three genes were amplified and sequenced, including internal transcribed spacer (ITS) region and part of the β-tubulin (TUB2) and elongation factor (EF1-α) genes. ITS, TUB2, and EF1-α sequences showed 99% homology with