Page 25 - 《广西植物》2025年第7期
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7 期                   弓正威等: 小麦重要农艺性状的 QTL 定位与候选基因分析                                       1 2 1 7

                 Abstract: Wheat is one of three major staple crops in the worldꎬ QTL mapping and candidate gene analysis of important
                 agronomic traits are beneficial for breeding new cultivars. In this studyꎬ the excellent wheat varieties Shumai 969 and
                 Shumai 830 were used to construct a recombinant inbred line (F7) population consisting of 89 linesꎬ and the reduced
                 representation genome sequencing technology was carried out to genotype this population and its parents. In fieldꎬ the
                 phenotype of plant heightꎬ uppermost ̄internode lengthꎬ awn lengthꎬ spike lengthꎬ flag leaf lengthꎬ flag leaf widthꎬ tiller
                 numberꎬ effective tiller numberꎬ thousand grain weightꎬ grain lengthꎬ grain widthꎬ and grain surface area were
                 measured. The complete interval mapping method was employed to locate the QTL sites controlling these agronomic
                 traits. The results were as follows: (1) A total of 27 QTLs were identified. These QTLs distributed on 13 distinct
                 chromosomesꎬ and explained 3.74% to 26.70% of the phenotypic variation of the agronomic traits. Among themꎬ the QTL
                 in the 608.58-609.12 Mb interval on chromosome 7B controlled both plant height and uppermost ̄internode lengthꎬ which
                 was identified by two years. The QTL in the 519.94-528.83 Mb interval on chromosome 5A controlled both tiller number
                 and effective tiller numberꎬ and the QTL in the 437.38-439.30 Mb interval on chromosome 5D controlled both thousand
                 grain weight and grain surface area. 7 QTLs located in the same positions as previously reported. (2) Functional gene
                 prediction within the QTL intervals successfully predicted two candidate genes associated with plant height traitsꎬ four
                 candidate genes linked to tiller traitsꎬ and three candidate genes attributed to thousand grain weight within the mapped
                 interval. The two candidate genes of plant height encoded a leucine ̄rich repeat receptor ̄like protein kinase family protein
                 and a gibberellin 2 ̄oxidase. The four candidate genes of tiller encompassed a auxin response proteinꎬ a RING/ U ̄box
                 superfamily proteinꎬ and two F ̄box proteins. The three candidate genes for the thousand grain weight encoded a leucine ̄
                 rich repeat receptor ̄like protein kinase family proteinꎬ a protein kinase family proteinꎬ and a chlorophyll a ̄b ̄binding
                 protein. The identified QTLs and predicted major genes in this research established a foundation for the meticulous
                 mapping and cloning of the candidate genes controlling the corresponding agronomic traitsꎬ and benefited breeding new
                 wheat cultivars.
                 Key words: wheatꎬ agronomic traitsꎬ genetic linkage mapꎬ QTL mappingꎬ candidate gene analysis




                小麦是全球最重要的粮食作物之一ꎬ为全世                            因发掘则是这一技术的基础ꎮ 因此ꎬ定位小麦重
            界人类提供了 20%的能量与蛋白质(Raman et al.ꎬ                    要农艺性状的 QTL 位点ꎬ发掘调节农艺性状的候
            2010)ꎮ 全世界小麦种植面积在 2023 年达到了 2                      选基因ꎬ对未来小麦新品种的培育、提高小麦产
            亿多公顷ꎬ产量接近 8 亿吨ꎮ 尽管如此ꎬ对于全世                          量、维持粮食安全具有重要意义ꎮ
            界大部分发展中国家和地区小麦的供给仍然不足                                  在小麦的整个生长过程中ꎬ许多农艺性状都
            (祁慧博等ꎬ 2015)ꎬ只有在 2050 年使小麦的产量                      会对小麦最终的产量产生影响(Chen et al.ꎬ 2012ꎻ
            增加 50%才能满足因全球人口增长而带来的需求                            Liu et al.ꎬ 2015)ꎮ 目前ꎬ研究比较多的农艺性状
            (Ray et al.ꎬ 2013)ꎮ 而 鉴 定 小 麦 重 要 农 艺 性 状          包括株高、穗下节长、分蘖数、千粒重等ꎬ并鉴定出
            QTL 位点、挖掘候选基因则是完成这一目标的有                            了大量 QTL 位点( Tshikunde et al.ꎬ 2019)ꎮ 近年
            效方法ꎮ 在小麦几千年的栽培历史中ꎬ为了提高                             来ꎬ张衡等(2023) 利用杂交构建出的 F2 群体ꎬ对
            产量ꎬ人们通过选择育种的方法对小麦的农艺性                              亲本与群体中的极端株系进行 BSA ̄Seq 测序ꎬ将
            状进行筛选ꎮ 随着育种技术的进步ꎬ育种家们开                             得到的 SNP 转化为 KASP 标记对群体进行分型ꎬ
            始使用杂交、诱变、多倍化的方式来改变小麦的农                             构建遗传连锁图谱ꎮ 在 4B 染色体上定位到了 2
            艺性状ꎬ从而提高产量ꎮ 最为著名的例子就是ꎬ在                            个 QTL 位点分别位于 40 ~ 482 Mb 和 92 ~ 105 Mbꎬ
            20 世纪 60 年代育种学家将来自农林 10 号的矮杆                       解释了 15.13%和 7.26%的表型ꎮ 赵蝶等(2023)
            基因应用到小麦育种当中ꎬ极大地提高了小麦的                              以 205 个家系的重组自交群体为材料ꎬ利用小麦
            产量(Worland et al.ꎬ 1998)ꎮ 在现代育种中ꎬ标记                55K SNP 芯片构建高密度遗传图谱ꎬ结合 3 年共 6
            辅助育种作为一种加快育种速度的新兴育种手段                              个环境的 表 型 数 进 行 QTL 定 位ꎮ 在 染 色 体 2B、
            已被广泛采用ꎬ数量性状位点( QTL) 定位、候选基                         4B、4D、5A、5B 上各检出 1 个与株高相关的 QTLꎬ
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