Research Of Mating Type And Vegetative Compatibility In Cordyceps Militaris Of Entomogenous Fungi

The research of radial growth and different age of Cordyceps militaris strains by the method of linear regression and the principal components analysis indicates that the mycelial growth of colony is stable and uniform.And the growth rate is the main factor to verify whether the mycelia radial steady growth.The fungal age and subculture have no effect on the radial growth.The preservation of C.militaris with the standard of formation of mycelia,conidia and fruiting bodies showed that mycelial plugs is suitable for preservation in 4oC(added peptone as a protective agent).The preservation period is suggested more than 12 months.The mating types of C.militaris strain were detected by using multiplex PCR.At the same time,MAT1-1-2 gene was detected by PCR.Also,the types of mating type are individed into single mating type and composite mating type.And the MAT1-1-2 gene is absent.The mating type of 303 single ascospore strains from pupa and artificial media was detected,and the proportion of mating type was closed to 1:1 and no devsion.The mating type distribution of single ascospore strains which isolated from the pupa and artificial media were consistent.And the frequency of MAT1-1 was more than MAT1-2.The mating type of the conidia from the single ascospore strain was the same as their parental strain.And the mating type of conidia from composite mating types was MAT1-2.The single ascospores were randomly selected for fruiting body production.It was found that a single mating type strain could not form fruiting bodies.And two opposite mating type strains were mixed cultured;the fruiting bodies were induced.However,when the MAT1-1-2 gene was absence in the strain with MAT1-1,it was unable to form the fruiting body after culture with MAT1-2 strain.The confront cultured of the single ascospore strains were observed at the interface between the mycelial growth of mycelium colony traits and the fusion of microscopic observations,the propotion of vegetative compatibility of same mating type strains was more than that in different mating type strains.At total,the MAT1-1-2 gene was associated with in the mating type.Composite of mating type strains were detected by nuclear staining.There were two nuclei in one cell in the conidia from ascospore strain.Heterokaryon strains could develop fruiting bodies.Therefore,it also can explain the two different nuclear MAT1-1 and MAT1-2 gene distributed in the same cells,which were contained two species of the nucleus.The growth of fruiting bodies was effected if the MAT1-1-1 gene was absence.