This study reports for the first time Colletotrichum siamense causing anthracnose on Blueberry (Vacciniun sect. Cyanococcus) in Brazil

). A multilocus Bayesian phylogeny placed isolate LFN0500 within the C. siamense clade (posterior probability = 0.96), together with the reference strain (ICM 18578). To confirm pathogenicity, 6-months-old blueberry seedlings and detached fruits (average diameter, 15 mm) were spray inoculated with a conidial suspension (1 × 106 conidia/mL), incubated at 25 ± 5 °C in the dark for 48 hours, and then transferred to a growth chamber. Seedlings and fruits exhibited typical anthracnose symptoms 13 and three days after inoculation, respectively, whereas the negative controls, sprayed with distilled water, remained asymptomatic. The pathogen was reisolated, fulfilling Koch's postulates. To our knowledge, this study is the first report of C. siamense causing anthracnose on blueberry in Brazil. The identification of C. siamense expands the known diversity of Colletotrichum spp. affecting blueberry and provides useful information of disease management in Brazilian orchards.