Molecular Identification And Phylogeny Reasearch On Russula In Yunnan

Russula has the most abundant species in Russulaceae.It has symbiosis relationship with trees as ectomycorrhizal. Many species of this genus has an important economic value, edible and medicinal. However, some species is poisonous even extremely toxic. Ingestion will be serious damage to health or even death. Therefore, the correct identification of species of great significance. Currently the approach of species identification include morphological identification and molecular identification. Morphological identification is mainly based on the shape and color of the cap, gill feature and the Health Information, stipe morphology, spore morphology, color and surface ornamentation, paste reactions. However, because of the tiny morphological differences between closely related species, the the presence of transitional form phenomenon and the morphological variation of the widespread species, resulting in the difficult even the error of morphological identification. In recent years, molecular methods which like TS, LSU, SSU, RPB2 sequencing and RAPD, to identify fungal species become an important adjunct.In this paper,15 species in Russula (19 samples) collected from Yunnan as study materials, molecular identification through ITS, LSU, SSU sequencing and phylogenetic analysis on them though maximum parsimony, Lactarius volemus as an outgroup. The main findings are as follows:①During molecular identification, ITS and LSU sequences are be able to distinguish the different species, however SSU sequences are not able to. Therefore SSU sequence is not suitable for systems research and identification on Russula.②Sample No.19 morphological identification results for R. omiensis, however ITS and LSU sequence alignment result on NCBI are Tricholoma aurantium; Phylogenetic analysis result based on ITS showed that, No.19 is gather together with R. omiensis with a higher support rate (94%); Phylogenetic analysis result based on ITS and LSU also showed that, No.19 is gather together with No.13 R. omiensis, Thus it is suggested the phylogenetic analysis based on ITS and LSU sequence on NCBI may may be incorrect.④In the phylogenetic tree based on ITS, Russula flavida, R. lepida, R. rosea, R. paludosa, R. vinosa and R. decolorans clustered into one category (support rate of 89%). R. vinosa and R. decolorans can not be completely separated, clustered into a small branch parallelly(support rate of 98%). Both of them are clustered into a small branch with R. rosea and R. Paludosa, R. aurea and R. grisea can not be completely separated (support rate by 72%). Also gather together with R. foetens as an independently clade (support rate of 100%) at an earlier evolutionary position.In the phylogenetic tree constructed based on LSU fragments, Russula virescens and R. lepida can not be completely separated (support rate of 99%).R. vinosa and R. decolorans can not be completely separated, clustered into a small branch parallelly(96% support). Both of them clustered with R.paludosa into a branch. Then clustered R. rosea into a large branch (the support rate of 70%). This result is consistent with the results of phylogenetic tree based on ITS.In the phylogenetic tree construct by splicing ITS and LSU sequences, R. vinosa and R.decolorans not be completely separated (99% support), This result is consistent with the results-based ITS phylogenetic tree. Both of them clustered with R.paludosa (75% support), The three also clustered with R. rosea into a large branch (97% support), It describes R. vinosa, R.decolorans, R.paludosa and R. rosea have a closer relationship. This result consistent with the phylogenetic tree construct based on ITS and based on LSU sequence.R.aurea, R. grisea and R. foetens can not be separated (the support rate of 100%). This result is similar with ITS based phylogenetic tree.