The Genetic Analysis Of Character Variation Of The Artificial Cultivation Of Cordyceps Militaris (cordyceps Militaris)

Cordyceps militaris(L.)Link is one of the most important fungus in cordyceps genus.It can replace the Cordyceps sinensis in diet and traditional Chinese medicine. In the artificial-planting,the strain of Cordyceps militaris is easy to degenerate.At present,the study about the fungus in Cordyceps Genus are just in the identification of fungi,the nutrition analysis,the using in medicine and artificial-planting.Although,it could reduce the lost by the usual breeding way,we could not solve the problem at basic.About the degeneration of strain,people mostly use the gender-cycling,the fusing-cytoplasmic technology and the genetic-engineering method to reform the strain.Most of people use moleculor method in the study of relationships among the species and between the species. We did not find none of the articles report about the genetic and degenerative mechanism.The degeneration of strain is common in artificial-planting,it is one of the most urgent problems that need to solve.In this experiment, PCR-RFLP and RAPD , were used to study the level of differences in gene of naturalized Cordyceps militaris and its degenerative strain.By using PCR-RFLP,5.8S and its two ITS regions were amplified and digested with five restriction enzymes (HaeⅢ,AfaⅠ,TagⅠ,AluⅠand XspⅠ).The sequencing results showed the length of 5.8S and ITS region is534bp and there are 13mutant bases.The sequence ofnaturalized strain is the same with the sequence searching in the Genbank.Of 80primers,9ones generated reproducible RAPDprofiles.From these 9primers we getthesimilar-ratio: betweenthenaturalizedCordycepsmilitarisanditsdegenerativestrain:OPG9:28.6%;OPH4:44.4%;OPH12:33.3%;OPL1:50%;OPL9:40%;OPM2:33.3%;OPM17:57.1%;OPM19:72.7%;OPG13:0. The maxim is 72.7% ,the average is 39.9%.The results showed the degenerative strain gene rated high frequency mutation. The mutation may associate with the gene which resulted in degeneration of the strain .The isozymes of the Cordyceps militaris and its degenerative strain on the stage of mycelia were analysed by polycrylancide gel electrophoresis. The tested isozymes included esterase(EST),superoxide dismutase(SOD),Malate.dehydrogenase(MDH),malic enzyme(ME),Glutamate dehydrogenase(GDH),peroxidase(PER) and alcohol dehydrogenase(ADH).There were obvious differences between the normal strain and its degenerative strain in EST,MDH,ME,SOD.The zymotype were the same in the other isozymes.The results were not only used to test the degenerative strain at young stage ,but also as the theoretical base to study the genetic mechanism of the degenerative strain.