Occurrence of Neopestalotiopsis rosae and Neopestalotiopsis zimbabwana Causing Leaf Blight in Blueberry in Mexico

Abstract

In Mexico, blueberries are an economically important crop, with annual production of more than 80,000 tons, making the country the world's fifth‐largest producer of this fruit. In spring 2024, chlorotic spots were observed that turned into localized necrotic lesions which eventually coalesced in two commercial rabbiteye blueberry fields in the states of Michoacán and Puebla, Mexico. Based on morphological features, Neopestalotiopsis ‐like colonies were consistently recovered from symptomatic tissues. Multilocus phylogenetic analyses (ITS, β‐tub and tef1 ‐α) identified the isolates as Neopestalotiopsis rosae and N. zimbabwana . Pathogenicity was demonstrated by inoculating each isolate onto healthy blueberry plants, which developed the characteristic symptoms of the disease 9 days after inoculation, thereby fulfilling Koch's postulates. To our knowledge, this is the first worldwide report of N. zimbabwana and the first report of N. rosae in Mexico causing leaf blight on blueberry. Leaf blight is an emerging disease in blueberry fields of Puebla and Michoacán, Mexico. Therefore, the epidemiological potential of the disease should be determined, and effective, sustainable management strategies should be developed.