论文部分内容阅读
利用粳稻Lemont导入籼稻特青背景构建的高代回交导入系和重组自交系群体,在北京和海南两地检测影响株高和剑叶宽的稳定表达的主效QTL,分析这些主效QTL在导入系和重组自交系群体的不同选择强度(5%、10%和20%)的极端群体中的等位基因偏离,研究不同性状的主效QTL对不同选择强度的响应及不同遗传结构群体对主效QTL人工选择响应的影响。结果表明,导入系的选择群体中所有主效QTL等位基因的偏离方向都使得供体等位基因频率增加,等位基因产生偏离的性状选择方向及供体等位基因的偏离方向与基因的加性效应方向完全一致,而重组自交系的选择群体中主效QTL等位基因的偏离既有供体等位基因增加的,也有等位基因降低的,两种群体中不同性状的主效QTL等位基因偏离与选择强度密切相关。通过比较不同群体结构的主效QTL定位及对选择响应的异同,发现一些假阳性QTL和在随机作图群体中漏检的QTL,强调作图群体QTL定位结果验证的重要性。鉴于不同群体、不同性状和不同主效QTL的选择响应特点,对不同主效QTL在基于常规表型选择和分子标记辅助选择回交育种中的利用价值及注意事项进行了探讨。
The major generation QTLs for stable expression of plant height and flag leaf width were detected in Beijing and Hainan by using the introduced high-generation backcross inbred lines and recombinant inbred lines constructed from the japonica rice Lemont, The allelic discrepancy in extreme populations with different selection intensities (5%, 10% and 20%) of the introduced and recombinant inbred lines population was used to study the response of the major QTLs of different traits to different selection intensities and the different genetic structures Effect of Population on Artificial Selection Responses to Main QTLs. The results showed that all the major QTL alleles in the selection population of the introgression lines were deviated from each other, which resulted in the increase of donor allele frequency, the trait selection of allelic deviation and the deviation of donor allele from that of gene The additive effect direction is exactly the same. However, the deviation of the major QTL alleles from the selected inbred lines of the recombinant inbred lines increased both the donor alleles and the alleles, and the main effects of different traits in the two populations QTL allele deviation is closely related to the intensity of selection. By comparing the QTL mapping of major QTLs and the response to selection in different populations, some false positive QTLs and QTLs missed in random mapping population were found, which emphasized the importance of QTL mapping results in mapping population. In view of the characteristics of QTLs response to different populations, different traits and different main effects, the value and precautions of different main QTLs based on conventional phenotypic selection and molecular marker-assisted selection backcross breeding were discussed.