| 摘要: |
| 【目的】对不同授粉方式下玉米籽粒品质性状进行QTL定位，揭示授粉方式对玉米籽粒品质性状的影响，为玉米籽粒品质遗传改良和分子育种提供理论基础。【方法】以优良玉米自交系KA105和KB020及用其构建的201个F5∶6重组自交系（RILs）群体为试验材料，于2019年在陕西榆林、汉中和杨凌3个地点种植。收集榆林、汉中的开放授粉果穗和汉中、杨凌的自交授粉果穗，开展玉米蛋白质、油分、淀粉、纤维等籽粒品质性状遗传分析，采用完备区间作图法（ICIM）对品质性状进行QTL检测。【结果】玉米RILs群体的蛋白质、油分、淀粉和纤维含量在两种授粉方式下存在差异，开放授粉下的蛋白质和纤维含量极显著低于自交授粉，油分和淀粉含量极显著高于自交授粉。方差分析结果显示，两种授粉方式下各品质性状在不同家系和环境间整体差异显著。相关性分析表明，开放授粉下玉米RILs群体籽粒品质性状含量与其对应的自交授粉下籽粒品质性状含量表现出极显著正相关，且蛋白质含量与淀粉含量呈极显著负相关，与纤维含量呈极显著正相关。共检测到16个QTL，其中开放授粉条件下检测到6个QTL，单个QTL解释的表型变异介于5.84%～14.56%；自交授粉条件下检测到 10个QTL位点，可解释5.69%～14.70%的表型变异。【结论】在两种授粉方式下能同时检测到2个与蛋白质含量相关的QTL（qPro9-1和qPro10），两种授粉方式下在10号染色体上的临近位置各检测到1个淀粉含量相关QTL（qOSta10-1和qSSta10-2），在开放授粉和自交授粉条件下各检测到1个纤维素含量相关特异QTL，分别检测到2个和3个与油分含量相关的QTL。 |
| 关键词: 玉米 籽粒品质性状 开放授粉 自交授粉 QTL定位 玉米育种 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金青年基金项目(31701438) |
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| QTL mapping of maize grain quality under different pollination methods |
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LI Ranran,ZHANG Xiuying,LI Ting,et al
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| Abstract: |
| 【Objective】The aim of this study was to reveal the influence of pollination methods on grain quality traits and provide basis for grain quality improvement and molecular breeding through QTL mapping of maize grain quality under different pollination methods.【Method】Excellent maize inbred lines KA105 and KB020 as well as 201 F5∶6 recombinant inbred lines (RILs) constructed with them were planted in Yulin,Hanzhong and Yangling,Shaanxi in 2019.The open pollinated ears from Yulin and Hanzhong and self pollinated ears from Hanzhong and Yangling were collected for QTL mapping of maize quality including protein,oil,starch and fiber using inclusive composite interval mapping (ICIM) method.【Result】Protein,oil,starch and fiber contents of RILs population were different between the two pollination methods.Protein and fiber contents of RILs population under open pollination were significantly lower than those under self pollination,while oil and starch contents were significantly higher than those under self pollination.The results of variance analysis showed that there were significant differences in quality traits among different families and environments under the two pollination methods.Correlation analysis showed that grain quality traits of RILs population under open pollination were significantly positively correlated with those under self pollination.Protein content was significantly negatively correlated with starch content,but was significantly positively correlated with fiber content.A total of 16 QTLs were detected,of which 6 were detected under open pollination explaining 5.84%-14.56% of phenotypic variation and 10 were detected under self pollination contributing to 5.69%-14.70% of phenotypic variation.【Conclusion】Two QTLs of protein content (qPro9-1 and qPro10) were detected simultaneously under the two pollination methods.Two QTLs of starch content（qOSta10-1 and qSSta10-2）were detected respectively at two adjacent positions on chromosome 10 under the two pollination methods.One specific QTL of fiber content was detected under open pollination and one was detected under self pollination.Two and three QTLs of oil content were detected under open pollination and self pollination conditions,respectively. |
| Key words: maize kernel quality trait open-pollination self-pollination QTL mapping maize breeding |
