Study On The Mating Type Of Morchella Spawns

Morchella,a rare edible and medicinal fungus,is loved by people all over the world for its unique culinary flavor.It was found that the sexual reproduction mode of Morchella was heterogenous copulation,that is,the existence of two mating genes was required for the normal development of fruiting bodies and the generation of ascospores.At present,several species have been successfully cultured in China,most of which are derived from tissue separation and spore separation.In the breeding process,there is no prior detection and screening of the type of bacteria contained in the mating,in the cultivation process is easy to be unable to mate,resulting in no or less fruiting.In this paper,the mating types of the spawns of Morchella importuna were isolated by tissue separation and spore separation were detected.The spawns with two mating types were repeatedly subcultured,and then the changes of their mating types were detected.The results are as follows:1.The using of different methods to obtain morel speciesIn October,Morchella importuna ZP-1466 with MAT1-1-1 mating type and S6 with MAT1-2-1 mating type were used as strains for mycelium culture.After the mycelium is covered by the fungus bag,it was they were buried in the treated experimental field.In early march of the following year,when temperatures picked up,large Numbers offruiting bodies began to be produced.The strains of the cultivated Morchella importuna were obtained by tissue and spore separation.Among then,7 strains were obtained by tissue separation of bacterial cap,3 strains were obtained by tissue separation of bacterial stalk,10 strains were obtained by single spore separation,and 7 strains were obtained by multi-spore separation.2.Distribution of mating type MAT1-1-1 and MAT1-2-1 between different strains of MorchellaOnly a single MAT1-1-1 cross type was obtained by tissue separation of Morchella cap and stalk.All strains isolated by single spore separation contained only one mating type,but their respective mating types were different,in which s-1,s-6 and s-9 contained a single mating type of MAT1-2-1,while S-2,S-3,S-4,S-5,S-7,S-8 and S-10 contained a single mating type of MAT1-1-1.Among the 7 strains isolated by polyspore separation,except that M-7 only has one MAT1-1-1 mating type,the other 6 polyspore strains have both MAT1-1-1 and MAT1-2-1mating types.3.Subculture of morchella polyspora strainWith the increase of culture time,mycelia of polysporous mycelia will gradually generate many different sizes of sclerotia,and the color of sclerotia and mycelia will gradually deepen.At the same time,the activity of mycelium decreased with the prolongation of culture time.However,the growth rate of mycelium would not be affected by the increase of transfer times in the process of multi-spore strain subculture.4.Variation of MAT1-1-1 and MAT1-2-1 mating types of morchella polyspora strains after secondary cultureSix polysporous strains with MAT1-1-1 and MAT1-2-1 mating types were cultured for 14 generations,and the mating types of M-1 and M-3were not changed.However,species M-2,M-4 and M-5 all lost MAT1-1-1 mating type in the 9th generation mycelium,and according to the detection results of the mating type in the 10 th to 14 th generation mycelium,the mating type was permanently lost.When the strain M-6was subculture to the eighth generation,the mating type of MAT1-1-1was lost.Meanwhile,the distribution of the mating type in the mycelium from the ninth generation to the 14 th generation also proved that the mating type was permanently lost.In this paper,27 strains were isolated by tissue and spore isolation methods.The mating type distribution of these strains was clarified by molecular identification.Six polyspora strains with both MAT1-1-1 and MAT1-2-1 mating types were subculture.It was found that the loss of mating type of MAT1-1-1 occurred when most strains were cultured in the 8th or 9th generation.The results of this paper have important guiding significance for the cultivation and production of Morchella: strain obtained by tissue isolation or single spore isolation only has a singlemating type.If single such strain is used for cultivation and production,it may not produce fruiting bodies normally.Therefore,it is necessary to pair the sex-matched strains so that they can cooperate with each other in order to cultivate Morchella.High and stable yield can be achieved in the process of bacteria production.The strains separated by polyspore method have two mating types,which can be used for production,but can not transfer too many times to avoid losing one mating type.