Genetic Differentiation Of Ophiocordyceps Sinenssis And Its Host Insects In Some Areas Deduced From ITS And COI Sequences

Due to intensifing exploitation by the local people over the past years, the Cordyceps sinensis resources has been on the verge of depletion in some areas. In addition, the situation is aggravating by grassland degradation and desertification. Hence, the conservation of natural Cordyceps resources is becoming urgent Meantime, studies of Cordyceps sinensis population in light of molecule, population genetic differentiation will play an important role in the rational utilization and protection of Cordyceps.This study determined ITS sequences and COI sequences of Cordyceps sinensis. The result indecated that the length of ITS fragment is between 503 and 515bp, the length of COI sequence length is between 601 and 663bp. We also empolyed 8 representatives sequence of Cordyceps sinensis from GenBank, and homologous sequences for related Chiiese Paecflomyces and Cordyceps to in our NJ molecular phylogenetic reconstruction. The results showed that 31 Cordyceps sinensis samples are divided into three clusters, there are 16 samples in cluster I including those from Yushu and Chengduo in Qinghai Province and Nakchu in Tibet; cluster II includes samples from Qilian and Gangcha in Qinghai As for the cluster III contains samples form the Baima Snow Mountain and Zhongdian, Yunnan Province. The above results are essentially consistent with those of the previous studies, That is, the genetic differentiation of Cordyceps sinensis is large latitudinal in the Qinghai-Tibet plateau.We observed that Ophiocordyceps sinensis and its host exhibit somewhat concerdant phybgenetic nelationship in their molecular phylogenetic trees. Thus, it can be generally inferred that Ophiocondyceps sinensis and its host has evolued a particular parasitic relationship. The causes of this concordance may lie in the following two aspects:One is that both have a common eco-geographical environment, because in light of distribution, both of which were distributed in the Qinghai-Tibet Plateau at the altitude of 3000-5000m Another possibility explanation is that long-term stress confrontation between Cordyceps fungus and its host hepiahis, causing them to have concordant.