Identification and pathogenicity of Lasiodiplodia and Neoscytalidium species associated with mango (Mangifera indica) dieback disease in Israel

Mango is affected by several fungal diseases, including dieback caused by species of the Botryosphaeriaceae family. Recently, mango dieback was reported from multiple locations in Israel. In this study, we isolated and characterized 11 representative fungal isolates belonging to Botryosphaeriaceae from symptomatic mango stems. Lasiodiplodia theobromae and Neoscytalidium dimidiatum are reported in this study as pathogens causing mango dieback in Israel, based on morphology, phylogenetic inference (using ITS and tef1-alpha regions) and pathogenicity assays. Representative isolates of L. theobromae and N. dimidiatum caused dieback symptoms on detached mango stems under controlled conditions and on mango trees outdoors, growing under natural conditions under shade nets. The pathogens were re-isolated from inoculated stems, fulfilling Koch's postulates. Lasiodiplodia theobromae has not been previously reported in Israel, while N. dimidiatum has been recorded on pitahaya fruit causing internal black rot disease. In this study, we report in detail on mango dieback caused by L. theobromae and N. dimidiatum in Israel. Considering the economic impact of dieback disease on mango yield, further studies on epidemiology will assist in developing disease management strategies.