| Wolfiporia cocos belongs to basidiomycetes, the sclerotium of W.cocos is an important traditional Chinese medicine. But for a long time, cultivation strains of W.cocos are relying on the method of tissue separation from sclerotium, which causes different traits of W.cocos strains. Introduction frequently between the W.cocos production areas, the phenomenon of different names for the same strain, brought hidden troubles and risks to the production of W.cocos. So far, the domestic W.cocos germplasm resources and their genetic relationship have not be researched systematically yet, which brought difficulties for utilizing and breeding of W.cocos germplasm resources.The68W.cocos strains for this research were collected and preserved in our laboratory. Several biological traits, such as three morphology traits of colonies, growth velocity in three different mediums, time that fulfilled the medium bags, activities of two extracellular enzymes, yield of sclerotium, contents of water-souble polysaccharide and triterpenoid, were measured and compared. Then the genetic relationship of the strains was analysised, which based on SSR polymorphisms.Colony phenotypes of the W.cocos strains on CYM were different. The growth velocities of W.cocos were different on different culture mediums, in general, the growth velocity of W.cocos on wheat medium> on pine sawdust> on CYM. The growth velocities of the W.cocos strains were between0.74cm/d-1.39cm/d on CYM,1.39cm/d-3.02cm/d on wheat medium and0.95cm/d-2.78cm/d on pine sawdust medium. The activities of extracellular carboxymethyl cellulose enzyme were between4.70u mol/mL· min-11.39μ mol/mL· min, and that of extracellular xylanase were between0.96μ mo1/mL· min-2.91μ mo1/mL· min. The average yields of sclerotia of each strain were between0.47kg/pit-1.38kg/pit in2013. The sclerotia yields of15strains were higher than the popupar cultivation strain T1. The contents of water-soluble polysaccharide in sclerotia were between3.07mg/g-6.61mg/g, and that of total triterpenoid were between7.12mg/g-11.99mg/g. Variance analysis showed that all these traits were different significantly or extremely significantly. Some biological traits of W.cocos showed significant correlation or extremely significant correlation. Average yield of sclerotium per pit showed positive correlation significantly with growth velocity on wheat medium. Time that fulfilled medium bags showed negative correlation significantly or extremely significantly with growth velocity on wheat medium, growth velocity on pine sawdust medium and activity of extracellular xylanase.According to the information of genome and transcriptome of W.cocos, several SSR locations were detected and SSR primer pairs were designed. A total of44polymorphism SSR primer pairs were selected. Clustering analysis of all the68strains was done based on the polymorphism SSR molecular markers. The genetic relationship of domestic W.cocos germplasm resources was very close, and56strains showed no difference. Two distinctive SSR molecule markers were founded. The No.13strain could be identified by the SSR molecule marker P105, and the No.44, No.45strain could be distinguished from the group by the other SSR molecule marker S76.The results showed that the strains of domestic W.cocos were different clearly in several biological traits, which provides references for selecting or breeding of excellent strains. Some traits showed significant or extremely significant correlation, which offers methods for excellent W. cocos strains selection at the beginning of breeding process. But the result also showed that the genetic relationship of the strains for this experiment was very close, and the genetic diversity of domestic W.cocos germplasm resources was low. The germplasm resources of W.cocos should be collected and protected for further research and utilization. |
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