Application Of RAPD, SRAP And ISSR Marker In Germplasm Resource Of Lentinula Edodes And Establishment Of Scar Marker

PCR-based DNA markers are increasingly widely used due to their simplicity and efficiency .which penetrated many fields of genetic and breeding research , identifying and cloning gene , studying genetic diversity and determining genetic relationships within and between species. In my studies on the germplasm resource in 40 cultivated strains of Lentinula edodeswith the use of molecular Markers are reviewed with emphasis on random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR), Sequence-related amplified polymorphism(SRAP), sequence characterized amplified region (SCAR). These markers have been demonstrated to be served as molecular tools for rapid and reliable detection for revealing genetic polymorphism in Lentinula edodes. In contrast to SCAR marker, RAPD, SRAP and ISSR marker are not enough reproduciable and stable. Many studies describing the development of SCAR markers from RAPD profiles were found, but few studies from ISSR profiles and no information from SRAP profiles were found.We believe this is the firs study establishing SCAR markers from SRAP profiles. Some markers are converted successfully into SCAR markers. These studies may provide information for enacting variety register to protect the breeder' s right.To optimize reaction system, the effects of main elements, i. e. temperature, Taq polymerase dosage, dNTP concentration, Mg²⁺ concentration, primer concentration and template DNA concentration on RAPD, SRAP and ISSR amplication were tested by single factor experiment .respectively, to determine their optimal levels and the optimal reaction system for the analysis is established. The average ratio of polymorphic bands in RAPD, SRAP and ISSR marker is 55. 8%, 51. 2% and 64. 8% respectively. Through the screening of the ISSR primers, we found that the genome of Lentinula edodes contains much 3-nucleotide repeats.