Identification of mating-type (MAT) gene, productivity and cordycepin content in medicinal Cordyceps militaris strains

Cordyceps militaris is a valuable medicinal fungus and has been widely cultivated. However, its frequent degeneration during continuous maintenance in culture leads to a dramatic reduction in productivity and cordycepin content in the fruiting body. Mating-type (MAT) genes play an important role in the formation of the fruiting body in C. militaris. The data of MATgenes, the productivity and quality of C. militaris strains being cultivated in Vietnam are the foundations for providing solutions to overcome the problem. In this study, eight strains were isolated and identified based on morphological characteristics and the ITS sequence of rDNA. MAT1-1-1 and MAT1-2-1 genes were determined in the 8 isolates, including 5 strains (QN6, HL11, HL12, TN01, and TN02) that possessed both MAT1-1-1 and MAT1-2-1 genes and the others (SH03, HL13, and HN01) has only MAT1-1-1 gene. All identified strains were able to form a fruiting body, especially, the SH03 strain performed the highest productivity and quality (fruiting body yield 31 g/box, biological efficiency 13.77% and cordycepin content 12.5 mg/g dried fruiting body). This fungal strain with a single mating-type gene is a promising candidate for applying to C. militarisproduction.