高产虫草素的蛹虫草新品种选育

Breeding of Cordyceps militaris with High Content of Cordycepin

摘要:

虫草素（3’-脱氧腺苷）具有抗肿瘤、抗菌、抗病毒、增强免疫力等多种生物活性功能，是蛹虫草（Cordyceps militaris）的核心生物活性物质。目前，蛹虫草中虫草素含量还偏低，且蛹虫草菌株易退化，急需选育高产优质的蛹虫草新菌株。作者以高产虫草素的蛹虫草CM17菌株和高产子实体的蛹虫草ZGCM菌株为亲本，从ZGCM菌株中分离只有MAT1-1基因的子囊孢子单孢菌株和从CM17中分离只有MAT1-2基因的分生孢子单孢菌株，将两种不同交配型的单孢菌株进行杂交，通过分子鉴定和生物特性筛选，获得子实体产量高且虫草素含量高的新菌株ZA10-C4。菌株ZA10-C4子实体中虫草素产量达到（12.82±0.85） mg/g，为亲本ZGCM的4.33倍，并且保持ZGCM高产子实体的特性。同时，采用改良的基因快速提取与标记方法对孢子菌株和杂交菌株进行MAT交配型基因鉴定，提高了育种的效率。

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.