The Construction And Application Of Genetic Linkage Map Based On The Genome Sequencing Of Flammulina Velutipes

The strains L11 and W23 of this study are got from Gao Wei who obtained the strains used the protoplast single nucleation technology. She crossed the two strains and got the haploid population stains which were the offsprings of the crossed strain 1123. The haploid population strains crossed with two test strains named 77and 53 got from Li Bo. After grown in the mushroom farm, a lot of traits data of the diploid strains were taken note.The DNA of L11, W23, 1123 was used as the PCR template to screen the RAPD primers. The specific bands between the two parents strains were chosen to clone and sequence with the aim to transform RAPD marker to SCAR marker finally. In the study, 923 RAPD markers were screened and 239 bands were collected. Based on cloned and sequenced 181 bands, 93 pairs SCAR marker were designed and 11 pairs were tested to be right. One conclusion that could be drawn from this research was that the method of obtaining SCAR marker from RAPD is not appropriate because the rate is only 11.8%.The genome of haploid strains L11 and W23 were sequenced and assembled to look for the different region to design dominant SCAR marker by comparison between them. 116 pairs of SCAR marker primers were designed with this method and 51 pairs of primers were suitable for genetic linkage map construction. The rate is 44.0%, which is higher than the one of transforming RAPD marker to SCAR marker and the method is more effective than the former.A genetic linkage map of Flammulina velutipes was constructed by SCAR markers and phenotype markers with software Mapmaker 3.0. The construction was based on the DH population data of PCR result amplified by 108 pairs of SCAR primers (including 45 pairs obtained by Gao Wei & Li Bo ). Using the Backcross data type, 73 markers were linked to 11groups with the LOD value 3 and max distance value 37.2 cM, which are the acquiescent parameters of the software. The length of the linkage map is 1639.9cM, the groups'length ranges from 16.5cM to 569.9cM, the average distance between two markers is 22.5cM.Two additive effect QTLs and a pair of epistasis QTLs were found used the software QTL Network-2.1 to analyze the data of genetic linkage map and traits data. The additive effect QTLs control the growth rate of monokaryotic mycelium on straw-based medium. One is located in the group 2 of W23 and the heritability of additive effect is 14.71%, the other one, group 4 of L11 and the heritability of additive effect is 14.15%. The epistasis QTLs control the product of population strains crossed by test strain 77and haploid population strains, the heritability of additive by additive effect is 28.65%.