Study On Genetic Diversity Of DNA Markers And Relationship Among The Strains In Agaricus Bisporus (Lange) Imbach

Agaricus bisporus（Lange）Imbach is the only one of the global cultivation of edible fungi, and its output at the top. Agaricus bisporus originated in France early in 1550, were introduced to China for more than 80 years. The introduction of new varieties from abroad or induction and hybridization in the process of cultivation, making our country’s Agaricus bisporus to occur various genetic variation, also to increase their species genetic diversity.In present study, through the optimiztion for annealing temperature of SRAP-PCR and the concentrations of Mg²⁺, Taq DNA polymerase, dNTPs, primers, template DNA in PCR mixture, to determine a suitable thermal program and amplification system of SRAP-PCR for Agaricus bisporus. Meanwhile, optimizztion for annealing temperature and amplification system including concentrations of Taq DNA polymerase, dNTPs, primers, template DNA, suitable to different ISSR primer’s to determine the thermal program and amplification system of ISSR-PCR for Agaricus bisporus.PCR testing for 56 pairs of SRAP primers, 20 ISSR primers and 99 RAPD primers respectively,53 pairs of SRAP primers, 10 ISSR primers and 56 RAPD primers were found to be able to amplify clear and stable DNA bands. The average ratio of polymorphic bands in SRAP, ISSR and RAPD marker is 70.21%, 78.33% and 61.94% respectively.41 840 data gotten from clear and stable DNA bands at 1 046 sites amplified by SRAP, ISSR and RAPD, coded by 0 or 1, were used to the cluster analysis by means of the between-groups linkage method and the similarity coefficient of Jaccard in the software of SPSS 11.0 for Windows, and to establish proximity matrix and the genetic relationship dendrogram among the 40 varieties of Agaricus bisporus. These 40 varieties have abundant genetic diversity because of their quite differences similarity coefficients,according to the proximity matrix. According to the genetic relationship dendrogram, 40 varieties could be classified into 9 major variety groups at 13 of distance value and classified into 6 major variety groups at 16 of distance value.Fifteen variety or variety groups-speciffic DNA bands with PCR stability were selected to be sequenced from the DNA fingerprint data obtained. According to the sequence data, 64 pairs of SCAR primer were designed for SCAR test. Six pairs of SCAR primer could be used to amplify 6 objective bands successfully. It indicated that these 6 specific fragments were converted into SCAR marker successfully, respectively. These 6 specific fragments were marked as A, C, E, G, H, J respectively, their relevant SCAR primers were A1, C4, E5, G5, H2, J3. Through combination among PCR results by A1, C4, E5, G5, J3, 40 varieties could be divided 6 major variety groups. This result is agreement completely with the result that 40 varieties were classified into 6 major variety groups at 16 of distance value in the genetic relationship dendrogram. Through combination among PCR results by E5, H2, J3, groupⅴand groupⅵwhich were divided at 13 of distance value could be distinguished from other groups. Additionally, sample 333 （No.01） could be identified by PCR with primer pair A1, directly.