Construction Of The Molecular Mapping Library Of The Main Cultivated Strains Of Lentinula Edodes In China

Lentinula edodes is an important edible fungus, today China accounts for about70%of its world production. There are lots of problems of Lentinula edodes strains, the same strain often called by different name or the different strain often called by same name, so we need to increase the management of strains. In recent years our country has adopted series of regulations and standards of species protection and species identification, but in practical work, we need take all varieties as the reference sample when identification of any varieties, and this increasing workload of genetic specificity identification of new varieties.In this study, SSR molecular markers were utilized to reveal the genetic analysis of25L. edodes strains which already identified by species, aim to explore the availability of SSR molecular markers in identification of L. edodes cultivate strains and build the genetic-specific molecular fingerprint of L. edodes cultivate strains, strive to lay the molecular biology foundation of varieties identification by cultivated L. edodes varieties and use of improved varieties, and at the same time provide the instructional methods and standards for the varieties identification of other edible fungus. The results showed:1. At last we screened out14pairs of primers including10pairs of self-designed primers and4pairs of primers from the literature from48pairs of primers including36pairs of self-designed primers and12pairs of primers from the literature.2. SSR analysis of25species of L. edodes which already identified by species by use14pairs of primers which was screened, polymorphisms of all primers were100%, the number of alleles ranged from2to9with the average value of5.0each primer; the number of genotypes ranged from2to12with average value of6.3each primer.3. SSR analysis of QingYuan9015and its four single spore strains:809(A1B2)、810(A2B1)、811(A2B2) and812(A1B1) by using Paa-1and F7this two randomly selected pairs of primers. The results showed that SSR molecular markers is co-dominant marker in L. edodes as same as in animals、plants and micro-organisms. 4. We calculated the genetic parameters of the results of SSR analysis, the observed heterozygosity ranged from0.0400to0.9200with average value of0.4857; the expect heterozygosity ranged from0.1151to0.8131with average value of0.6216; and PIC values ranged from0.1064to0.7736with average value of0.5541. Comprehensive analysis shows that the distinguish effect of12pairs of primers is better, and the other two pairs of primers S4and S15is poor, at the same time the comprehensive distinguish effect of all14pairs of primers is well.5. We calculated the genetic distance of all25varieties of L. edodes, results showed that the minimum genetic distance is0.0000which between ShengXiang10and ShengXiang12; the maximum genetic distance is2.3885which between XiangJiu and L9319, and the average is0.6407.Of all25varieties, except ShenXiang10and ShenXiang12that cannot be separated, other23varieties were separately from each other. We build a fingerprints of25varieties of L. edodes by using amplification profiles of tested strains genomic DNA by14pairs of primers, compared with RAPD, ISSR and other identification methods, the dates obtained here can be the fingerprints which have good reproducibility and can be compared between laboratories of cultivars of L. edodes, and no longer need all varieties have been identified as the reference in specific identification of species identification, so the workload is greatly reduced.