Research On The Mycelium Growth And Laccase Expression Characteristics Of Tricholoma Mongolicum

Tricholoma mongolicum is precious edible and medical fungi on grassland in north China,and its nutrition rich balanced and medicinal ingredients diversiform,make it have the high utilization value and development prospects,and it is also an important part of the biological chain on grassland.At present,Tricholoma mongolicum have been listed in the National Key Protected Wild Plants(second batch),so it is very necessary to strengthen its physiology and domestication cultivation technology research and protect this precious species.In this study,in order to provide experimental material to realize the artificial domestication and cultivation of Tricholoma mongolicum,we studied the basidiospores germination and biological characteristics of primary hypha,and to identifiy the mating types of Tricholoma mongolicum,to determine laccase activity,and to explore the impact on laccase gene expression of secondary hyphae with low temperature stimulation.The main conclusions are as follows:1.Basidiospores of Tricholoma mongolicum were kidney-shaped or oval,(4?6)?mx(6-9)?m;It takes a week at least when basidiospore can germinate and become macroscopic tiny colony;Adding 1.5 g/L yeast extract and 1.5 g/L caseein hydrolysate to the MS medium can promote the basidiospores germination.2.According to colony growth speed and morphology of primary hypha,we found that there are five distinct types in primary hypha:Hypha tomentum type,Hypha adhesion type,Hyphae thin type,Clusters growth type and Tardiness growth type.3.The mating type of Tricholoma mongolicum is tetrapolar mating system,and factor A and B are no linkage.We observed that four kinds of typical colony morphology of mating reaction:Affinity reaction,The fence reaction,Appressed reaction,No border incompatible reaction.4.In this study,there are secondary mycelium of Tricholoma mongolicum as our experimental materials.We studied the effects of the low temperature stimulation to laccase activity and transcription of the laccase gene family on Tricholoma mongolicum:1)The different strains of Tricholoma mongolicum have different laccase activity.There is larger change of laccase activity with the continuous growth of mycelium,and it is the overall downward trend.2)With the low temperature stimulations,there is increase or decrease in different degrees of the transcriptional level of laccase gene family on Tricholoma mongolicum.It can be inhibited the transcriptional level of laccase gene family significantly for 5?,be improved for 10?,and have obvious change of the transcriptional level of laccase gene family for 15?.With the improvement of processing temperature,the general trend of the transcriptional level of laccase gene family is the first increase and then decrease.Under the all conditions of experimental treatment,the low temperature stimulating with 10? for 10 days has the best effect on the increase of laccase activity of Tricholoma mongolicum.