Microstructure And Ultrastructure Observation Of Fruit Bodies,Mycelia And Primordia Of Xerocomus Spadiceus

Xerocomus spadiceus belongs to Xerocomus,Boletaceae,Boletales,Agaricomycetes and Basidiomycota.As a kind of world wide fungi,boletus are delicious taste,rich nutrition and have high medicinal value,so popular with people.But the boletus are seasonal occurrence,low yield and have limited resources,and in recent years,with the increasing demand for people,together with excessive picking and increasing destruction of the ecological environment,it is difficult to achieve sustainable development and utilization only by field resources.Boletus almost belongs to the mycorrhizal fungi,at present,except for a few of saprophytic species,most can not be artificially cultured,they just stayed in the stage of mycelia in pure culture conditions and the mycelia grew slowly,it were difficult to form the primordia,carry out the late development,form fruit bodies,and complete the whole life history.The present study on boletus mainly focused on classification,nutriention analysis,hyphae induced and medium optimization,mycelia fermentation and extraction of active ingredients and so on,the basic research remains weak.Because of the complex habitats,the natural life history and mechanism of growth and development still are not clear.Xerocomus spadiceus is a typical representative of Yunnan boletus,and through continuous exploration in recent years,it has been induced primordia under the experimental conditions.Therefore,in this paper,Xerocomus spadiceus as experimental material,in order to understand it's life history,by fluorescence staining,scanning electron microscopy and transmission electron microscopy,the formation process of basidiospores in field mature fruit bodies and microstructure and ultrastructure of three main growth stages(fruit bodies,mycelia and primordia)were studied.The studies will provide a important basis for enriching the cytological theory of large mycorrhizal fungi and for the artificial cultivation of boletus and other rare wild edible fungi in the future.The main study results are as follows:1.Basidiospores generated from paliform arrangement basidia,in the hymenium each of basidium bears four spores,the majority of which have one nuclear;the mature spores appeared ablong shap and had smooth surface,with a size of 8?10 ?m×3?m.2.The suitable medium for spores germination was(1 L):potato 200 g,glucose 20 g,peptone 2 g,yeast 2 g,agar 9 g?MgSO40.5 g.KH2PO40.46 g?K2HPO41 g;45 ?thermal stimulus was required before spores inoculated,the optimum culture temperature was 35 ?;when germinating,most of the primary hyphae budded at the long axis spores,and a few of them at the side;and the primary hyphae had single nuclei.3.The diameter of mycelia in cap were about 3.5 ?m,hyphal surface smooth,cells arranged irregularly and closely without clamp;Most cells binuclear,in which containing mitochondria,ribosomes,vacuoles and other organelles,and having conidia;The diameter of mycelia in pure culture were about 1.7 pm,hyphal surface smooth,cells binuclear,without clamp connection,above-mentioned organelles could also be observed in cell;The diameter of mycelia in primordia were about 2.5 ?m,organelles above still present.These showed that the cells of hyphae these three periods were all binuclear.Under pure culture,condition mycorrhizal fungi yet can't be induced primordia,so there are few cytological studies at different developmental stages.In the paper,the cell morphology and nuclear number in three different developmental stages(the fruit bodies,hyphae and primordia)were studied comparely,the suitable conditions for basidiospores culture explored.These above were the main innovation of this paper.