There are about one thousand of known fungal species capable of killing insects, most of which are ascomycetous fungi. The species like Metarhizium anisopliae, M. robertsii, M. acridum and Beauveria bassiana have been developed as environmentally friendly biological control agents against different insect pests. The species of Cordyceps militaris and C. sinensis (syn. Ophiocordyceps sinensis), however, are best known as traditional Chinese Medicines that have been used for hundreds of years in Eastern countries.
Our group is mainly focused on the studies of these fungi at genomics, transcriptomics and functional genomics levels to understand the strategies/mechanisms employed by the fungi to interact with their insect hosts. We sequenced different species/strains of the ascomycete insect pathogenic fungi and the phylogenomic analyses indicate that fungal entomopathogenicity has evolved multiple times, but with a similar expansion of protease and chitinase protein families, an indication of convergent evolution during fungal adaptation to insect hosts. Gene function studies are focused, in particular, on the receptors, effectors and transcription factors putatively involved in the fungus-insect interactions. We are also interested in exploring the functions of those genes responsible for the biosynthesis of bioactive secondary metabolites and fungal sexuality control in insect pathogenic fungi. Based on the understanding of fungal molecular pathogenesis, genetic engineering of insect pathogenic fungi will be conducted to improve the control efficacies of mycoinsecticides.
Insect cadavers colonized by the species of Metarhizium robertsii, M. acridum, Beauveria bassiana,Ophiocordyceps sinensis, Cordyceps militaris and C. cicadae , respectively.