Study On Monospore Crossbreeding Of Hypsizygus Marmoreus And Its Genetic Diversity

Hypsizygus marmoreus is one of the important edible mushrooms industrialized cultivation in China.Degeneration of cultivated strains and the long growth cycle are the important problems of H.marmoreus industry.In this study,the aim was to obtain high quality and yield new strains using monokaryon-monokaryon crossing to select hybrid strains,and molecular marker technology of ISSR、RAPD and SRAP were used to analyze the genetic diversity of the parental and hybrid strains,and screen out the rich polymorphism,clear band and stablefingerprints,which can provide a valuable reference for H.marmoreus breeding.The research results were as follows:(1)Monokaryon-monokaryon crossing: 10 monokaryotic strains of WZ-5 and WZ-77 were obtained by monosporous hybridization and culture.100 hybrid strains were obtained by hybrid breeding.The results of the antagonism test and microscopic examination,100 hybrid strains had clamp connection.The fruiting body cultivation experiments of 14 hybrid strains showed that 10 hybrid strains could grow normally.Obviously,the fruiting bodies of hybrid strain ZJ-15 were excellent,and its cap without white tumors was different from other strains which had more or less white tumor cap.The fresh weight of ZJ-15(252.54 g per bottle)was higher than that of the parental WZ-5(235.00 g),and lower than that of WZ-77(400.00g),the biological efficiency of ZJ-15 was 77.37%.The hybrid strains ZJ-20 fresh weight was393.00 g per bottle and the biological efficiency was 120.40%.(2)ISSR molecular marker: 20 ISSR primes were used to analyze 16 H.marmoreus strains by ISSR molecular marker,10 ISSR primers were selected and obtained 71 special bands.The amplified bands of ISSR per primer was 7.10.From the special bands there were57 polymorphism bands which covered 80.28% and 5.7 polymorphism bands per primer,the percentage of polymorphism was 81.4% per primer.The coefficient of genetic similarity between 16 H.marmoreus strains was 0.5775～0.8451,and the average genetic similarity of these strains was 0.701.(2)RAPD molecular marker: 20 RAPD primes were used to analyze 16 H.marmoreus strains by ISSR molecular marker,10 RAPD primers were selected and obtained 77 special bands.The amplified bands of ISSR per primer was 7.30.From the special bands there were73 polymorphism bands which covered 95.1% and 7.3 polymorphism bands per primer,the percentage of polymorphism was 81.4% per primer.The coefficient of genetic similarity between 16 H.marmoreus strains was 0.5775～0.8451,and the average genetic similarity of these strains was 0.739.(2)SRAP molecular marker: 64 SRAP primes were used to analyze 16 H.marmoreus strains by ISSR molecular marker,10 SRAP primers were selected and obtained 77 special bands.The amplified bands of ISSR per primer was 7.70.From the special bands there were56 polymorphism bands which covered 71.8% and 5.6 polymorphism bands per primer,the percentage of polymorphism was 81.4% per primer.The coefficient of genetic similarity between 16 H.marmoreus strains was 0.4737 ～0.9079,and the average genetic similarity of these strains was 0.641.In this study,ZJ-15 and ZJ-20 obtained by monosporic hybridization possess high yield and good quality,and have a good application prospect.Through ISSR,RAPD and SRAP markers,the hybrid strains showed high genetic diversity,which laid a foundation for the identification of different strains.