Phylogenetic and morphological re-evaluation of the Botryosphaeria species causing diseases of Mangifera indica.

Species of Botryosphaeria are among the most serious pathogens that affect mango trees and fruit. Several species occur on mangoes, and these are identified mainly on the morphology of the anamorphs. Common taxa include Dothiorella dominicana, D. mangiferae (= Natrassia mangiferae), D. aromatica and an unidentified species, Dothiorella 'long'. The genus name Dothiorella, however, is acknowledged as a synonym of Diplodia. This study aimed to characterize and name the Botryosphaeria spp. associated with disease symptoms on mangoes. To achieve this isolates representing all four Dothiorella spp. mentioned above were compared with the anamorphs of known Botryosphaeria spp., based on conidial morphology and DNA sequence data. Two genomic regions were analyzed, namely the ITS rDNA and beta-tubulin regions. The morphological and molecular results confirmed that the fungi previously identified from mango as species of Dothiorella belong to Fusicoccum. Dothiorella dominicana isolates were identical to isolates of F. parvum (teleomorph = B. parva). A new epithet, namely F. mangiferum, is proposed for isolates previously treated as D. mangiferae or N. mangiferae. Isolates of D. aromatica were identified as F. aesculi (teleomorph = B. dothidea). A fourth Fusicoccum sp. also was identified as those isolates previously known as Dothiorella 'long'. A key is provided to distinguish these species based on anamorph morphology in culture. This study provides a basis for the identification of Botryosphaeria species from mango, which is important for disease control and to uphold quarantine regulations.