Inheritance Analysis And Mapping QTLs Related To Protein And Oil Content Of Soybeans

This study employed the soybean Recombinant Inbred Lines(RILs) containing 133lines from the cross Wan82-178×Tongshanbaopihuangdoujia as experimental materials.The protein and oil were estimated by major gene plus polygene mixed model in 2004 and2005. The result indicated that protein content was controlled by polygenes in two years.The heritability values were about 79.65% and 85.7%. However, they were different in oilcontent. Oil content was controlled by two major genes plus polygene in 2004, and theheritability value of major gene was about 48.43%; the polygene heritability value wasabout 37.79%. It was controlled by polygenes in 2005, and the heritability value was about80.8%.This sudy constructed a genetic map based on SSR markers using this RIL asexperiment materials. 95 pairs of SSR markers were employed to generate this genetic mapby Mapnaker/Exp3.0b, and the SSR genetic linkage map of soybean was constructed onwhich 56 markers distribute among 16 linkage groups and spanning soybean genome about630.5cM with average distance between markers being 11.5 cM. Based on this linkage map,the composite interval mapping was used to identify quantitative traits loci (QTL)associated with Soybean protein and oil content, plant height, yield and 100-grain weight in2004 and 2005.6 QTLs were detected for 5 traits. In 2004, the QTLs related to oil content,height and yield were located in the same marker interval. Only QTLs related to rpotein andoil content were detected in 2005. It was found that the results of mapping QTL for oilcontent were similar in these two years. They were both mapped near satt331 on linkagegroup wt-11, and explained 13.95% and 15.01% of the total variation of the oil content,respectively. In addition, the software QTL Mapper 1.6 was applied to detect QTLs relatedto oil content in two years. The result indicated that the QTL related to oil content was stillmapped near satt331 on linkage group wt-11.Another objective of this study was to select a mutant line with high protein content among the M₄ generation treated with ⁶⁰Coγ-ray. The results of filed test and qualityexaminations in 2003, 2004 and 2005 implied that the major agronomic traits were nearlyidentical, with the exception of the protein content between the mutant and control (i.e.without radioactive treatment), and the NIL was thus constructed. One thousand ten pairs ofSSR primers were applied to reveal the difference at genome level, and only three primerswere found polymorphic between the mutant and the control.