Phylogenetic And Population Genetic Diversity Analysis Of Lactarius Deliciosus

Lactarius deliciosus is ectomycorrhizal fungi important to pine and have an edible and medical value. China has a vast territory. Geography and climate environment is very complex breding a rich resources of L.deliciosus. L.deliciosus has an important economic and ecological value. It have been studied that nutrition and active ingredient, fermentation and cultivation and so on. Little is known about molecular systems and genetic diversity of L.deliciosus. Molecular technology has the advantages of simple, high specificity and reliability which made it an important tool in researching fungal genetics. Molecular technology have been used in the research of ectomycorrhizal fungi more and more. Phylogeny and genetic diversity is the theoretical basis for species identification and protection. This paper studied the L. deliciosus phylogeny and genetic diversity. Through the method of single nucleotide polymorphisms (SNP) and inter-simple sequence repeat markers (ISSR). The main task of the paper is to study the base variation of L. deliciosus in ITS sequence and phylogenetic position of L. deliciosus in Lactarius and the genetic diversity of L. deliciosus and the genetic relationship of L. deliciosus from different regions.The main conclusions are as follows:(1) Base variation of L. lactarius and phylogenetic analysis of L. deliciosus ingenus Lactarius. The genomic DNAs in the fruiting bodies of L. delisiosus、L. hatsudake、L. akahatsu and L. salmonicolor from different regions were extracted and ITS sequences were amplified by PCR for the purpose of comparing the ITS variation and analyzing phylogeny in the genus lactarius. Base composition、variable sites and base substitution type of L. deliciosus in ITS sequences were studied and phylogenetic tree was constructed. The result show:there are20bp length variation in ITS sequences and the percentage of bases C、T is higher than bases A、G. There are99variable sites in ITS sequences(ITS158,5.8S4,ITS237). Transition between T and C is the main variant type. Transitionsal sites and Transversional sites in ITS sequences are8and5respectively. The R value in ITS1、5.8S、ITS2are2.34、1.95、1.12. Genetic distance of L. deliciosus from different regions were calculated based on ITS sequences, the maximal genetic distance appeared between Jiangxi and Italy、Spain, France and Spain being0.012.The minimal genetic distance appeared between Yunnan and France being0. Phylogenetic tree indicated L. deliciosus has a close relation with L. hatsudake、L. akahatsu.(2) Genetic diversity and genetic relationship of L. deliciosus from different regions. ISSR molecular marker technology was adopted to analysis diversity of90L. deliciosus.6primers get103DNA fragments,17.2per primer,5-27fragments from different primers. There are one hundred and three loci were produced from these primers of which89loci (86.4%) were polymorphic. The size of these loci ranged from200bp to3100bp. The observed number of alleles was1.4215and the effective number of alleles was1.0236for every locus; Nei’s genetic diversity was estimated to be0.0834, while Shannon’s information index was0.2728, the gene flow was2.9573.L. deliciosus have a high gene flow in china. L. deliciosus from different regions have an unconspicuous clustering relations.