New species and records of Botryosphaeriales (Dothideomycetes) associated with tree dieback in Beijing, China.

Botryosphaeriales species are important pathogens that have worldwide distribution. In this study, 23 Botryosphaeriales strains were isolated from 13 host species during a dieback disease survey in Beijing, China. Based on morphological and phylogenetic analyses, six Botryosphaeriales species were identified, including two new species named Dothiorellahortiarborum sp. nov. and Phaeobotryonfraxini sp. nov. , and four new host records: Aplosporellaginkgonis from Cotinuscoggygriavar.cinereus, A.javeedii from Acermiyabei , Acertruncatum , Forsythiasuspensa , Lagerstroemiaindica , Sambucuswilliamsii , Syringavulgaris , Ulmuspumila , Xanthocerassorbifolium , A.yanqingensis from Acertruncatum , and Do.acericola from Forsythiasuspensa , Ginkgobiloba , and Syringaoblata . This study enriches the species diversity associated with tree dieback in Beijing, China, and contributes to the further study of the taxonomy of this order.