Occurrence of Alternaria alternata Causing Leaf Blight of Blueberry in Mexico

From November 2023 to February 2024, severe leaf blight symptoms were found on blueberry ( Vaccinium corymbosum L.) plants in a commercial field in Navolato, Sinaloa, Mexico. Three single-spore isolates were obtained and identified as Alternaria alternata by phylogenetic analyses of concatenated sequences of the gapdh, rpb2, and tef1-α genes. The pathogenicity of the isolates was confirmed by inoculating conidial suspensions on healthy blueberry leaves. This represents the first report of A. alternata causing leaf blight of blueberry in Mexico.