植物学报 ›› 2025, Vol. 60 ›› Issue (3): 342-353.DOI: 10.11983/CBB24047  cstr: 32102.14.CBB24047

• 研究论文 • 上一篇    下一篇

基于高密度Bin图谱的水稻苗期耐热性QTL定位

赵凌1, 管菊1, 梁文化1, 张勇2, 路凯1, 赵春芳1, 李余生1, 张亚东1,*()   

  1. 1 江苏省农业科学院粮食作物研究所, 国家水稻改良中心南京分中心, 国家耐盐碱水稻技术创新中心华东中心, 江苏省优质水稻工程技术研究中心, 南京 210014
    2 江苏省农业科学院无锡分院生物育种研究室, 无锡 214000
  • 收稿日期:2024-03-28 接受日期:2024-05-27 出版日期:2025-05-10 发布日期:2024-05-30
  • 通讯作者: 张亚东
  • 基金资助:
    江苏省种业振兴“揭榜挂帅”项目(No.JBGS(2021);江苏省种业振兴“揭榜挂帅”项目(No.JBGS(040)

Mapping of QTLs for Heat Tolerance at the Seedling Stage in Rice Based on a High-density Bin Map

Zhao Ling1, Guan Ju1, Liang Wenhua1, Zhang Yong2, Lu Kai1, Zhao Chunfang1, Li Yusheng1, Zhang Yadong1,*()   

  1. 1 Jiangsu High Quality Rice Research & Development Center, East China Branch of National Center of Technology Innovation for Saline-Alkali Tolerant Rice, Nanjing Branch of China National Center for Rice Improvement, Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
    2 Biological Breeding Research Laboratory, Wuxi Branch of Jiangsu Academy of Agricultural Sciences, Wuxi 214000, China
  • Received:2024-03-28 Accepted:2024-05-27 Online:2025-05-10 Published:2024-05-30
  • Contact: Zhang Yadong

摘要: 鉴定控制水稻(Oryza sativa)高温耐性的新位点和候选基因, 可为耐热遗传育种提供理论支撑, 具有重要的实践意义。利用粳稻(O. sativa subsp. japonica)品种TD70和籼稻(O. sativa subsp. indica)品种Kasalath衍生的重组自交系(RILs)群体为研究材料, 构建基于深度重测序的高密度Bin遗传图谱; 使用QTL IciMappingv软件基于完备复合区间作图法对水稻苗期高温胁迫下的幼苗存活率进行QTLs分析。共检测到26个控制苗期耐热性QTLs, 分布在除第3号染色体外的11条染色体上, LOD值为2.59-16.15, 其中4个QTLs的LOD值大于10, 7个QTLs与已知高温耐性QTLs的位置存在重叠或者部分重叠, 其主效QTL位点qHTSR5.2位于第5号染色体26.25-26.38 Mb区间, LOD值为16.15, 解释7.18%的表型贡献率。对4个主效QTLs区间进行基因功能注释和亲本间序列分析, 共发现27个注释有功能且在2个亲本间编码区存在非同义突变的基因。根据候选基因SNP的类型对RILs群体家系进行基因等位型分类和效应分析, 发现5个基因不同等位型的RILs群体家系高温处理后的幼苗存活率存在显著差异, 推测可能为候选基因, 可用于后续水稻高温耐性的分子机理研究。

关键词: 耐热性, 高密度Bin图谱, QTL定位, 水稻, 苗期

Abstract: INTRODUCTION: As the main grain crop, rice plays an important role in ensuring food security of China. Rise in global average temperature is detrimental to crop yield and heat stress is currently one of the major abiotic threats on rice production. There are significant variations in heat tolerance among different rice varieties. As a typical quantitative trait, heat tolerance of rice is controlled by multiple genes. Identification of new QTLs and genes related to heat tolerance is very important for the genetic research and the breeding of new heat-tolerant rice varieties. RATIONALE:In recent years, many heat tolerant QTLs had been identified with different genetic populations and evaluation indicators at different growth stages. Most of those QTLs were mapped in large intervals due to the limited population sizes, simplified experimental designs and inaccurately controlled environments. The heat tolerance level identification in a population is very difficult for mature plants. Therefore, we developed a population of recombinant inbred lines (RILs) with 186 lines derived from japonica rice TD70 and indica rice Kasalath, which showed large variations in seedling survival rates under high temperature stress (HTSR). QTLs associated with HTSR were mapped by the high-density linkage Bin-map and candidate genes were identified. RESULTS:Twenty-six QTLs related to the HTSR were mapped on 11 of the 12 chromosomes, with the exception of 3. The LOD values of single QTL ranged from 2.59-16.15, four of which with LOD values greater than 10. Seven QTLs were located within the same interval or adjacent to known heat tolerance QTLs. The major locus of qHTSR5.2 was located in the 26.25-26.38 Mb region of Chr. 5 with an LOD value of 12.07, which explained 7.18% of the total phenotypic variation in the HTSR. According to the annotation and sequence analysis of the genes located in the region of four major QTLs,we found that twenty-seven annotated genes with non-synonymous mutations in the coding regions between TD70 and Kasalath. Five of them were identified as potential candidate genes because the RILs sharing each of the distinct haplotypes of their parents for each gene exhibited significant different HTSR resistance level. Among them, three candidate genes encode heat shock proteins HSP20 or HSP17.5. CONCLUSION: We detected 26 QTLs controlling seedling heat tolerance based on a high-density Bin map in a RIL population. Some of the QTLs were overlapped with known heat tolerance loci, indicating their strong effects on regulating heat tolerance of rice. Five candidate genes were identified through gene annotation, parental sequence comparison, effect analysis of heat tolerance between RILs with different haplotypes. The candidate genes identified in our study could be used for molecular mechanism research on high temperature tolerance of rice in the future.

Mapping of QTL for heat tolerance at seedling stage in rice based on a high-density Bin map. Heat tolerance of parents and RILs population during seedling stage. Location of QTLs contributing to heat tolerance at seedling stage.

Key words: heat tolerance, high-density Bin map, QTL mapping, rice, seedling stage