Abstract:Cordycepin (3’-deoxyadenosine), which is the core bioactive ingredient of Cordyceps militaris, has various biological activities, such as anti-tumor, anti-bacterial, anti-virus and immunity enhancement. However, the content of cordycepin in Cordyceps militaris is low and the strain of Cordyceps militaris is easily degenerated. It is urgent to breed high-yield and high-quality Cordyceps militaris strains. In this study, Cordyceps militaris CM17 strain with high yield of cordycepin and Cordyceps militaris ZGCM strain with high yield of fruiting bodies were used as the parents. The ascospore monospora strain with MAT1-1 genotype was isolated from ZGCM and the conidia monospora strain with MAT1-2 genotype was isolated from CM17. Hybridization between the strains of single spore with different MAT genotype was studied through cross-breeding. A new strain ZA10-C4 with high yield of fruiting bodies and high content of cordycepin was successfully obtained through molecular identification and biological characteristics screening. The yield of cordycepin in hybrid strain ZA10-C4 was as high as (12.82±0.85) mg/g in fruiting bodies, which was 4.33 times higher than that of parent strain ZGCM. And ZA10-C4 maintained the characteristics of ZGCM with high yield of fruiting bodies. At the same time, an improved rapid gene extraction and labeling method was used to identify the MAT gene of spore strain and hybrid strain, which improved the efficiency of breeding.
