Phylogeny and pathogenicity of fungal species in the family botryosphaeriaceae associated with mango (Mangifera indica) in Thailand

Fungal species belonging to the family Botryosphaeriaceae are cosmopolitan and important pathogens of a wide range of plant hosts which include mango. Based on only morphological study, these fungi have been traditionally identified as genus Lasiodiplodia on mango in Thailand and mainly named as Lasiodiplodia theobromae. In this study a combination of morphology and phylogenetic inference were used to correctly identify isolates resembling botryosphaeriacous fungi that obtained from mango in Thailand. Phylogenetic inference applied here clearly revealed six clades together with the isolates obtained from Thailand grouping with Lasiodiplodia spp., which included L. pseudotheobromae, Lasiodiplodia sp., and L. viticola. To our knowledge, this study represented the first report of L. pseudotheobromae associated with mango in Thailand. Pathogenicity test was performed on mango fruits, stemends, and trees of the Mahachanok and Keawmorakot cultivars indicated that endophytic fungi might change to be opportunistic pathogens and pathogenic as latent pathogens when plant under stress or favorable environments for diseases development. In this study L. pseudotheobromae and L. viticola were the most pathogenic on the fruits and stem-ends, whereas L. pseudotheobromae and Lasiodiplodia sp. were more pathogenic to the inoculated trees.