First report of molecular characterisation of Fusarium proliferatum associated with root rot disease of Indian mulberry (Morinda officinalis How.) in Viet Nam

Root rot is the most serious disease affecting Indian mulberry in Viet Nam. The objective of the present study was to confirm the identities and pathogenicity of species of Fusarium isolated from the roots of Indian mulberry. Based on pathogenicity assays, F. proliferatum was shown to be the pathogenic agent. The identity of F. proliferatum was confirmed by PCR and phylogenetic analyses based on the sequences of the ITS region and the TEF1- gene. Of four semi-solid media (CA, PDA, CDA and YMA) tested, PDA was the most suitable medium for the growth of F. proliferatum. The optimal temperature range for the growth of F. proliferatum was 20-30 degrees C with a maximum at growth rate at 25 degrees C. The optimum pH for growth ranged from pH5.0-6.0 with maximum growth at 5.5. This is the first report of F. proliferatum causing root rot of Indian mulberry in Viet Nam.