中国农业科学 ›› 2026, Vol. 59 ›› Issue (3): 499-514.doi: 10.3864/j.issn.0578-1752.2026.03.003

• 作物遗传育种·种质资源·分子遗传学 • 上一篇    下一篇

冬小麦千粒重的全基因组关联分析及候选基因预测

王勇胜1,2(), 牛丽1,2, 王长杰1,2, 马立花1,2, 廉潇潇1, 孟亚雄1,2, 马小乐1,2, 姚立蓉1,2, 张宏1,2, 杨轲1,2, 李葆春2,3, 王化俊1,2, 司二静1,2(), 汪军成1,2()   

  1. 1 甘肃农业大学农学院,兰州 730070
    2 省部共建干旱生境作物学国家重点实验室,兰州 730070
    3 甘肃农业大学生命科学技术学院,兰州 730070
  • 收稿日期:2025-07-31 接受日期:2025-09-15 出版日期:2026-02-01 发布日期:2026-01-31
  • 通信作者:
    司二静,E-mail:
    汪军成,E-mail:
  • 联系方式: 王勇胜,E-mail:wangys1125@163.com。
  • 基金资助:
    甘肃省现代寒旱特色农业种业攻关项目(ZYGG-2025-3); 甘肃省现代寒旱特色农业种业攻关项目(ZYGG-2026-18); 甘肃省现代寒旱特色农业种业攻关项目(ZYGG-2025-12-3); 甘肃农业大学大学生创新训练项目(202501078); 甘肃省重点人才项目(2023RCXM70); 中央引导地方科技发展资金(25ZYJA002); 甘肃省现代寒旱特色农业麦类产业技术体系(GSARS-07); 甘肃省教育厅产业支撑计划(2021CYZC-12); 甘肃省自然科学基金重点项目(24JRRA637); 甘肃省农业农村厅种业攻关项目(GYGG-2024-2); 甘肃省科技计划(24CXNA038); 甘肃农业大学伏羲青年英才计划(Gaufx-03Y06); 甘肃农业大学伏羲青年英才计划(Gaufx-04Y011)

Genome-Wide Association Study and Candidate Gene Identification for Thousand Grain Weight in Winter Wheat

WANG YongSheng1,2(), NIU Li1,2, WANG ChangJie1,2, MA LiHua1,2, LIAN XiaoXiao1, MENG YaXiong1,2, MA XiaoLe1,2, YAO LiRong1,2, ZHANG Hong1,2, YANG Ke1,2, LI BaoChun2,3, WANG HuaJun1,2, SI ErJing1,2(), WANG JunCheng1,2()   

  1. 1 College of Agronomy, Gansu Agricultural University, Lanzhou 730070
    2 State Key Laboratory of Aridland Crop Science, Lanzhou 730070
    3 College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070
  • Received:2025-07-31 Accepted:2025-09-15 Published:2026-02-01 Online:2026-01-31

摘要:

【目的】小麦千粒重作为直接影响最终产量的核心要素,其遗传解析至关重要。精准鉴定调控该性状的稳定显著关联位点及其关键候选基因,为分子标记辅助选育高千粒重、高产小麦新品种提供理论依据和遗传资源。【方法】通过对291份不同来源小麦种质资源进行100K SNP芯片基因型分型,并结合连续2年采集的千粒重表型数据及其最优无偏预测值(best linear unbiased prediction,BLUP),利用基于P+K模型的混合线性模型(mixed linear model,MLM)实施全基因组关联分析(genome-wide association study,GWAS)。最终,对定位到的显著关联位点进行单倍型分析。【结果】291份小麦千粒重在2年间及BLUP值下均呈广泛变异(均值38.24—38.82 g,变异系数17.62%—19.93%),2年间的千粒重相关系数为0.88(P<0.01),与BLUP值的相关系数均为0.97(P<0.01)达极显著水平。基于291份冬小麦种质资源的千粒重表型数据在不同环境条件下均呈现正态分布特征,符合全基因组关联分析对数量性状数据分布的基本要求,表明该数据集适用于后续关联分析。GWAS分析共检测到19个与千粒重显著相关的SNP位点,分布在3B、5A和7A染色体上,能够解释6.85%—9.68%的表型变异,其中,有16个标记在2个及以上的分析环境中出现,是比较稳定的SNP标记。通过对多环境下存在且表型贡献率高的多效应位点进行单倍型分析,位于7A染色体的7A_145980808位点发掘到与千粒重显著相关的Hap1、Hap2、Hap3和Hap4等4个不同单倍型,其中,Hap4是高千粒重单倍型(P<0.01),而Hap2为低千粒重单倍型(P<0.01)。4种单倍型分别占72.36%、14.55%、8.73%和4.36%。具有单倍型Hap1、Hap2、Hap3和Hap4的品种(系)的国内材料占比表现为Hap3(95.83%)>Hap4(83.33%)>Hap1(77.39%)>Hap2(65.00%)。通过分析高千粒重单倍型Hap4,发现其在分布上主要集中于西北冬麦区,尤其是甘肃来源的品种。基于关联分析结果,在3B、5A和7A染色体上筛选多环境显著性关联位点,并以其上下游3.6 Mb区域作为置信区间,共鉴定出95个候选基因。最终通过联合基因注释与基因表达情况,获得4个可能与小麦千粒重相关的候选基因。【结论】揭示了16个与千粒重显著关联的稳定位点,鉴定出4种不同单倍型,并筛选到4个关键候选基因。这些基因主要参与碳水化合物合成与转运、细胞壁多糖组装、蛋白质稳态维持,以及淀粉合成基因的转录调控等生理过程。

关键词: 小麦, 千粒重, SNP标记, 全基因组关联分析, 单倍型, 候选基因

Abstract:

【Objective】Thousand-grain weight (TGW), a key determinant of final wheat yield, is of great importance for genetic dissection. Precise identification of stable loci and key candidate genes controlling TGW provides theoretical foundations and genetic resources for marker-assisted breeding of high-TGW and high-yield wheat varieties. 【Method】A total of 291 wheat accessions from diverse origins were genotyped using a 100K SNP array. TGW phenotypic data collected over two consecutive years and their best linear unbiased predictions (BLUPs) were analyzed using a genome-wide association study (GWAS) based on a mixed linear model (MLM) incorporating both population structure (P) and kinship (K). Significant loci were further subjected to haplotype analysis. 【Result】TGW showed broad variation across years and BLUP values (mean: 38.24-38.82 g; coefficient of variation: 17.62%-19.93%). The correlation between years was 0.88 (P<0.01), and correlations with BLUP values reached 0.97 (P<0.01). Phenotypic data displayed normal distributions under different environments, meeting the basic requirements for GWAS. A total of 19 SNPs significantly associated with TGW were detected on chromosomes 3B, 5A, and 7A, explaining 6.85%-9.68% of the phenotypic variation; 16 of them were repeatedly detected across multiple environments, indicating stability. Haplotype analysis at locus 7A_145980808 revealed four haplotypes (Hap1-Hap4), of which Hap4 was associated with high TGW (P<0.01) and Hap2 with low TGW (P<0.01). The frequencies of Hap1-Hap4 were 72.36%, 14.55%, 8.73%, and 4.36%, respectively. Domestic accessions were enriched for Hap3 (95.83%) and Hap4 (83.33%), with Hap4 predominantly distributed in the Northwestern winter wheat region, especially in germplasm from Gansu. Candidate gene mining within 3.6 Mb regions flanking significant loci on chromosomes 3B, 5A, and 7A identified 95 genes, among which four were highlighted based on gene annotation and expression profiles. 【Conclusion】GWAS identified 16 stable SNP loci significantly associated with TGW, four distinct haplotypes, and four key candidate genes. These genes are mainly involved in carbohydrate synthesis and transport, cell wall polysaccharide assembly, protein homeostasis, and transcriptional regulation of starch biosynthesis, providing valuable targets for molecular breeding of high-yield wheat.

Key words: wheat, thousand-grain weight, SNP markers, GWAS, haplotype, candidate genes