Study On Screening High-quality Polyorus Umbellatus And Growth And Development Process Of Sclerotium

Polyporus umbellatus (Pers.) Fries. is one of traditional and medicinal fungi species andits perennial sclerotium has been conceived as medicinal parts. However the shortage of wildP. umbellatus resources in recent years has been increasingly serious, which indicated urgentneeds for the realization of its standardized cultivation. In our study, wild and high-yieldcultivation of P. umbellatus was isolated, then different isolation methods, mediums,environmental and nutritional conditions were used to explore the optimal culture conditionsand to accelerate the domestication of the wild strain. Excellent strains were also screenedfrom the repository. Changes in sclerotia, hypha structure and content of effectivecomposition were all analyzed during their growth, development and the process when P.umbellatus interacted with A. mellea. All these above will deeply reveal the growth anddevelopment characteristics of P. umbellatus, and provide theoretical guidance for optimizingcultivation and technique system of P. umbellatus. Main results include:1. The spore separation method was better than sclerotium tissue separation, andgermination, growth of P. umbellatus mycelium were better when GPY, PDA and malt juicemedium were used as the separation medium.2. Organic carbon (especially dextrin, fructose) and nitrogen source (especially silkwormchrysalis powder, casein) which significantly promoted the growth of mycelial were moresuitable than inorganic carbon and nitrogen source. Low concentration of growth factor,especially corn starch also promoted the growth of hyphae, and Mn showed the best effectamong all tested mineral elements. The most appropriate condition for hypha growth was: pH6.0(initial),23℃, cultivated darkly.3. Filling material which mainly contained humus soil, sticks and leaves was moreconducive to the growth of mycelium, while a relatively slow growth rate in mycelium and along sclerotium forming time were found when traditional generation materials were used,which were not recommended in large-scale and artificial cultivation.4. SPSS clustering analysis and principal component analysis on10strains revealed that,comprehensive properties of5#,2#and1#strains were excellent due to the fact of their fastgrowing rate in hyphae, high yield and high content of polysaccharides. Thus these strains canbe used in mass production. 5. The degrees of hyphal differentiation, compact structure and skin lignification in wildsclerotia increased with their growth. And polysaccharide content increased as well, whileergosterol content rose and then fell. Polysaccharide and ergosterol content in myceliumcultivated via liquid fermentation were higher than wild sclerotia at each stage.6. Defense structures including thickening and lignification of cell wall, junior andsecondary isolation chamber appeared in wild sclerotia after the infection of A. mellea.Additionally, polysaccharide and ergosterol content increased firstly and declined lastly afterinfection.