Diversity And Biological Characteristics Of Wild Armilaria In Zhaotong, Yunnan Province

Armillaria mellea is a kind of medicinal and edible value of higher fungi.It is also an essential fungus for planting traditional medicinal Gastrodia elata.In recent years,the introduction of exotic A.mellea in Zhaotong,the main producing area of Yunnan Province,causes the reduction of G.elata and great economic loss due to strain degeneration in the planting process of G.elata.After investigations,it was found that some species of A.mellea from the local forest are used to cultivate G.elata,which not only has high yield but also has good quality.This fact indicates that there are high diversity of A.mellea species available for the production of G.elata in this area.In this experiment,the wild Armillaria in some woodlands in Zhaotong area was investigated and sampled.On the basis of morphological characteristics and classification,the fruit bodies,rhizomorph and spores of Armillaria was collected from 5 sites in Zhaotong,and were studied by traditional culture and isolation technology and DNA sequencing technology.The fruit bodies was divided into 16 groups by morphological identity.Totally 40 strains were obtained by traditional culture method.For each strain,firstly,we measured the biological characteristics including the colony diameter,the rhizomorph length,the branches of the rhizomorph,the color of the rhizomorph,and the growth rate.Secondly,IGS(intergenic spacer)fragment of 40 wild Armillaria strains were sequenced and 13 OTUs were identified if 97%similarity of IGS sequence was defined as a OTU.Through phylogenetic analysis,all OTUs were genus Armillaria.Among of them,one OTU is Armillaria sinapina species,and the rest strains can not be designated at species level.Finally,in order to evaluate the decomposition and utilization of woods by wild Armillaria in Zhaotong,it was determined that the cellulose and lignin decomposition ability,as well as the laccase enzyme activity of these strains.It was found that all strains have the ability to decompose lignin,but not one can break down cellulose.The laccase activity of strains is between 0 and 16.75 U/mL.On the whole,there are rich wild Armillaria species in Zhaotong area,and can be used as an important strain resource bank for G.elata cultivation?...