| Molecular genetic map is regarded as a powerful tool for the research of chromosomal structure variation, genome evolution and gene order as well as a important base for gene mapping, gene cloning and molecular assistant breeding. A high-density map will beneficial for solution to these questions. The more dense the markers on a genetic map get, the higher practical value of the map. With drawbacks of the previous map (the big gap and abnormal marker distribution) in mind, we collected great amounts of published markers, and used the markers developed by BAC end sequencing to improve the previous map. In addition, we investigated effects of detection for the QTL mapping using the improved map. The results are as follow:1. Totally778primer pairs were detected for polymorphism, which is comprised of448SSRs,162STSs,48IPs and120BAC ends. Among them,155primer pairs were found to be polymorphic between the parents, with the estimated polymorphic frequency of18.77%.164marker loci genotyped using these polymorphic primer pairs have been added to the previous map to improve it.2. The improved linkage map consists of506loci, with the calculated genetic distance of1849.3cM,153.9cm longer than the previous one. The averaged interval size has decreased to3.7cM,1.3cM shorter than the previous one.3.34.3%of the markers genotyped were found to be skewed. The number of markers skewed to the high oleic parent was larger than that skewed to all other five possible types. The distorted loci were usually clustered in the end of a linkage group.15SDR have been detected. The distorted marker percentage was the highest in the groups A6and A7.4. Re-scanning of QTLs using the improved map showed that one or more QTLs were found for content of major fatty acids except the stearic acid. The position of the QTLs was close to the previous result. However, confidence intervals of a few QTLs decreased and more minor QTLs were found after addition of new marker loci into the improved map. |
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