Entomopathogenic fungi (Cordyceps spp.) isolated from emerging insect pests associated with plantation forests in Vietnam

Plantation forests accounted for 4.4 million hectares out of 14.7 million hectares of total forest area in Vietnam, and contribute greatly to the export of timber and wood products as well as the livelihoods of the mountainous people. Several species of insect pests have been observed in Dendrocalamus barbatus, Chukrasia tabularis, Acacia and Eucalyptus plantations. However, these pests were found to be parasitized by entopathogenic fungi. The aims of this study are to evaluate pathogenicity and identify taxonomy of the entopathogens obtained from Ceracris kiangsu, Episparis tortuosalis, Batocera lineolata and Endoclita sp. Results showed that seven entomopathogenic fungi were found from these four pests in which C. kiangsu had 2 isolates, E. tortuosalis had 2 isolates, B. lineolata had 1 isolate, and Endoclita sp. had 2 isolates. In addition, all isolates expressed pathogenicity in Galleria mellonella larvae with the parasitized percentage ranged from 73 to 100%. Based on ITS, LSU and TEF1-α sequence analysis, the identified entomopathogenic fungi belong to the genus Cordyceps. This finding suggests a great potential for application of these Cordyceps isolates in insect pest management programs in Vietnam.