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草业学报 ›› 2025, Vol. 34 ›› Issue (10): 174-186.DOI: 10.11686/cyxb2024456

• 研究论文 • 上一篇    

长穗偃麦草响应NaHCO3胁迫的离子平衡机制及转录组分析

张然1(), 刘琛琢1, 苑峰2, 刘亚玲2, 董笛1, 王思宁1, 邹博坤1, 李晓霞1()   

  1. 1.中国林业科学研究院生态保护与修复研究所,国家林业和草原局草原研究中心,北京 100091
    2.内蒙古草业技术创新中心有限公司,内蒙古 呼和浩特 010070
  • 收稿日期:2024-11-19 修回日期:2025-01-09 出版日期:2025-10-20 发布日期:2025-07-11
  • 通讯作者: 李晓霞
  • 作者简介:E-mail: lixiaoxia@caf.ac.cn
    张然(1995-),女,山西绛县人,助理研究员,博士。E-mail: zhangran@caf.ac.cn
  • 基金资助:
    中国林业科学研究院基本科研业务费专项资金项目(CAFYBB2022XA002);2023年国家草业技术创新中心(筹)重大创新平台建设专项(CCPTZX2023B01)

Ion balance mechanism and transcriptome analysis of Elytrigia elongata in response to NaHCO3 stress

Ran ZHANG1(), Chen-zhuo LIU1, Feng YUAN2, Ya-ling LIU2, Di DONG1, Si-ning WANG1, Bo-kun ZOU1, Xiao-xia LI1()   

  1. 1.Institute of Ecological Protection and Restoration,Chinese Academy of Forestry,Grassland Research Center,National Forestry and Grassland Administration,Beijing 100091,China
    2.Inner Mongolia Grassland Technology Innovation Center Co. ,Ltd. ,Hohhot 010070,China
  • Received:2024-11-19 Revised:2025-01-09 Online:2025-10-20 Published:2025-07-11
  • Contact: Xiao-xia LI

摘要:

长穗偃麦草因其较强的耐盐碱能力常被广泛用于建植盐碱地牧场。为探究其响应盐碱胁迫的离子平衡机制,本研究以长穗偃麦草‘Orbit’为试验材料,设置150 mmol·L-1的NaHCO3溶液人工模拟碱胁迫,测定了幼苗生长指标及矿质离子(Na+、K+、Ca2+、Mg2+、Cl-、SO42-和NO3-)含量,并利用高通量Illumina Hiseq测序技术对正常处理(CK)和胁迫24 h NaHCO3处理下的叶片和根系进行了转录组学分析。结果表明:NaHCO3胁迫下,长穗偃麦草幼苗根系生物量显著增加,根冠比增大。转录组结果表明,NaHCO3处理下叶片中有1833个差异基因(different expression genes, DEGs),根系中有1536个DEGs,140个基因在叶片和根系中均差异表达。GO和KEGG富集分析发现,叶片和根系中的DEGs均显著富集在与抗氧化相关、离子结合相关、苯丙氨酸和苯丙烷类生物合成等代谢通路;离子结合通路相关DEGs包括BAK1CIPK10STRK1WAK8及多条laccase基因(laccase-11laccase-3)等,可能参与了长穗偃麦草对NaHCO3胁迫的响应过程。此外,生理试验结果进一步证明长穗偃麦草叶片和根系的离子转运与分配受到影响,表现为Na+大量积累,而对K+的吸收能力下降,K+/Na+下降,根系通过提高对其他阳离子(如Ca2+、Mg2+和Fe3+)的吸收及分配能力来保持体内营养均衡,以更好地适应盐碱环境。本研究结果可为牧草及其他作物耐盐分子育种提供优异基因资源,还可为长穗偃麦草推广及盐碱地改良利用提供理论依据。

关键词: 碱胁迫, 长穗偃麦草, 差异表达基因, 离子稳态

Abstract:

Elytrigia elongata, due to its strong salt-alkali tolerance, is widely used to establish salt alkali pastures. This research explored the ion balance mechanism of E. elongata in response to salt-alkali stress, using the cultivar ‘Orbit’ as the experimental material, and 150 mmol·L-1 NaHCO3 to simulate alkali stress. The growth indexes and mineral contents (Na+, K+, Ca2+, Mg2+, Cl-, SO42- and NO3-) of seedlings were determined, and high-throughput Illumina Hiseq sequencing technology was used to perform transcriptomic analysis on leaves and roots after exposure to contrasting normal (CK) growth conditions and NaHCO3 treatment for 24 hours. It was found that the root biomass and root-shoot ratio of E. elongata increased significantly under NaHCO3 stress. RNA-Seq results showed that there were 1833 differentially expressed genes (DEGs) in the leaves and 1536 DEGs in the roots under NaHCO3 treatment, and 140 genes were differentially expressed in both leaves and roots. GO and KEGG enrichment analysis revealed that DEGs in leaves and roots were significantly enriched in metabolic pathways related to antioxidant synthesis, ion binding, and phenylalanine, and phenylpropanoid biosynthesis. DEGs related to ion binding pathways included BAK1CIPK10STRK1WAK8, and multiple laccase genes (laccase-11 and laccase-3), which may be involved in the response process of E. elongata to NaHCO3 stress. In addition, physiological test results further demonstrate that the ion transport and distribution in the leaves and roots of E. elongata are affected. This was evidenced by a large accumulation of Na+ and a decrease in ability to absorb K+, resulting in a decrease in the ratio of Na+∶K+. The roots maintained tissue ion balance by improving the absorption and distribution capacity of other cations such as Ca2+, Mg2+ and Fe3+, so as to better adapt to the saline-alkali environment. The results of this study identify specific genes involved in salt-tolerance, and will be useful to inform molecular breeding of forage and other crops. These results also provide a theoretical underpinning for the promotion of E. elongata and the improvement and utilization of saline-alkali land.

Key words: alkali stress, Elytrigia elongata, differentially expressed gene, ion homeostasis