Study On The Genetic Diversity Of Protoplast Hybridization And Self-crossing Strains Of Lentinus Edodes

As the largest edible fungus in China,lentinus edodes have both nutrition and health care value.L.edodes have played an important role in improving people’s lives and combating poverty,and will play a more active role in rural revitalization.However,due to the low investment in scientific research of edible fungi such as L.edodes in the past,more research on genetic breeding is needed.Therefore,this project in the national edible fungus industry technology system with mushroom posts,the 12 parent strains of L.edodes were evaluated for somatic incompatibility,esterase isoenzymes,and agronomic traits,and two strains of L.edodes XG4619 and XT08 with long genetic distance and complementary advantages were selected.The protoplast mononucleation of the two strains was carried out to analyze the existence of single polarization.The experiment carried out the mating of mitotic products(protoplasts)and meiotic products(spores),and to analyze the physiological,biochemical and phenotypic differences of parental and progeny(F1,F2),so as to provide support for the further development of L.edodes breeding with genetic theories,methods and germplasm resources.The results are as follows:(1)Parent evaluation and screeningThe 12 parent isolates of L.edodes showed rich genetic diversity in somatic cell incompatibility,bioesterase isoenzyme and phenotypic agronomic traits.Two strains XG4619 and XT08,which had far genetic distance and complementary advantages,were screened for protoplasmic preparation and mononucleation test.(2)Optimize the preparation conditions of protoplasm systemThe effects of enzymolysis temperature,enzymolysis time and concentration of stabilizer on the preparation of protoplasm were studied.The optimal preparation conditions of protoplasm were as follows: enzymolysis temperature 30℃,enzymolysis time 3.5h,and concentration of stabilizer mannitol 0.6mo L/L.(3)Genetic characteristics of protoplast hybridizationBy protoplast technology,XG4619 got 3 protoplast mononuclear(namely b19,b20 and b28);XT08 got 3 protoplast mononuclear(namely T21,T24,T28,T29 and T30).The protoplast mononuclear strains of each tested strain were of the same mating type.The F1 hybrid strains(b19×T21,b19×T24,b20×T30,b28×T30),which were interbred with XT08 mononuclear strains,showed genetic differences in physiology,biochemistry and phenotype.These results revealed that haploid binuclear cells in each cell of L.edodes secondary mycelium,as mitotic products,seem to exist independently,but in essence,some genetic material exchange or recombination took place.(4)Genetic diversity of self-pollinating strainsOne of F1 hybrid strain(b19×T21)was randomly selected for single sporulation isolation,and 195 meiotic products(spores)were obtained.Single spore germination after the formation of mononuclear strains,the selection of two mating type(set mating type A1B1)same mononuclear strains,respectively,with another 50 mating type(A2B2)different selfing mononuclear strains,selfing strains F2 on hypha growth speed,strong edge density,colony morphology,as well as significant genetic diversity,and two mating type hybrid strains of the same(A1B1)in mononuclear strains also exist differences between product that meiosis(spore)strong reorganization.(5)4 protoplast hybrid strains and 195 mononuclear strains were obtained.