Identification And The Corresponding Fruiting Conditions And Mechanism Of A Wild Agaricus Bisporus

China is a vast land and has a lot of wild edible mushrooms,which is very delicious,nutritious and is favored by people.The separation and domestication of wild mushrooms resources is a problem to need solving in order to develop edible mushroom industry of China.A strain of wild mushroom G1 was isolated from Xiaodian District of Taiyuan in Shanxi Province.The aim of this work was to carry out the identification of G1 strain,and study its biological characteristics and the domestication.Then,the conditions of forming fruit bodies for G1 strain was explored on the wheat extract agar medium.At last,the fruiting mechanism of G1 strain was studied.The main results were the following:1.A preliminary identification of wild mushroom G1 strain was carried out.The PCR amplification of G1 DNA with universal primers 1TS1 and ITS4 was done.The PCR products were sequenced and compared with those registered sequences on GenBank.The newly derived ITS sequence was deposited in GenBank under accession number KT781515.ITS sequence of G1 strain and 20 model strains of Agaricus were used to construct the phylogenetic tree,and found that G1 strain showed highest similarity to Agaricus bisporus and Agaricus bitorquis.After observing the basdiospore of fruit bodies by scanning electron microscope,in combination with other morphological characteristics of this strain,wild mushroom G1 strain was identified as A.bisporus.2.The biological characteristics and domestic cultivation of A.bisporus G1 strain were carried out.The results showed that the optimum stock medium for G1 strain was dung medium.On the dung medium,mycelia of G1 strain grew significantly faster without aerial mycelia and the growth speed reached 2.36 mm/d.The most suitable carbon source for the growth of G1 mycelia was maltose.G1 strain could make good use of the organic nitrogen.It could also grow when using the ammonium nitrogen,but grew poor on nitrate nitrogen.The results showed that G1 strain could grow under 15-35?and 25?was more suitble temperatures.G1 strain grown fastest and best in the media of pH 6 to 7,and indicated that the G1 favored the neutral acidic environment.By cultivating G1 strain with a procedure based on the method of A.bisporus using the rice straw and cow manure compost,the fruit bodies were obtained.The analysis results showed that the nutrient composition contents of G1 fruit bodies were generally higher than that of A.bisporus As2796.So the G1 strain has higher economic value and potential medicinal value,and was worth studying further.3.The fruiting conditions of G1 strain was explored on the wheat extract agar(WEA)medium.The mycelia of G1 strain could grow in WEA media of pH 5.0 to 10.0.However,the primordial formation and fruiting occurred in pH 6.0 to 8.0,and under pH value of 6.0,the primordial formation and fruiting time was the shortest.The mycelia could grow under continuous light,darkness and alternation of light and darkness(12h/12h),and the mycelial growth speed was almost same.However,G1 strain could form primordia and fruit bodies only under continuous darkness at 15-30?.The development time from primordia to fruit bodies at 15?was longer than that at 20?to 25?.The WEA medium was optimized through one-factor-at-a-time experiments and response surface method in order to decrease the fruiting time.The results showed that when adding 17.7 g/L maltose and 2.0 g/L peptone in WEA medium,the fruiting time of G1 strain was 14 days,which decreased 16 days as compared with the control.4.In order to clarify the fruit bodies formation mechanism of G1 strain on agar medium,the volatile components produced by G1 strain in different growth and development periods in WEA medium were separated and identified their structures by using the headspace solid phase microextraction method.As2796 strain in mycelial growth period served as the control.On basis of analysis on the difference between these volatile components,the preliminary conclusion could be drawn:the primordial formation and fruiting of G1 strain could be adjusted by the volatile components Ethyl benzene,o-Xylene,p-Xylene,1-Octanol,Trans-2-Octen-1-ol,6-Methyl-5-Hepten-2-one,Benzaldehyde and 3-Methyl-Butanal,which were all metabolized by G1 strain.It was also possible that these volatile components played common regulation role on the primordial formation and fruiting by working in coordination and collaboration.