中华金叶榆盆栽苗对干旱胁迫的生理响应与转录组分析  

Physiological response and transcriptome analysis of potted seedlings of Ulmus pumila‘Zhonghua Jinye’under drought stress

作　　者：张世英 刘易超 贾树强 李泳潭 黄印冉 杨敏生 张军 ZHANG Shiying;LIU Yichao;JIA Shuqiang;LI Yongtan;HUANG Yinran;YANG Minsheng;ZHANG Jun(Department of Forestry Science,Hebei Key Laboratory for Tree Genetic Resources and Forest Protection,Hebei Agricultural University,Baoding 071000,China;Hebei Academy of Forestry and Grassland Science,Shijiazhuang 050061,China;Ninghe District Seedling Improved Seed Service Center,Tianjin 301509,China)

机构地区：[1]河北农业大学林学院/河北省林木种质资源与森林保护重点实验室,河北保定071000 [2]河北省林业与草原科学研究院,河北石家庄050061 [3]天津市宁河区苗木良种服务中心,天津301509

出　　处：《河北农业大学学报》2022年第1期69-78,共10页Journal of Hebei Agricultural University

基　　金：河北省林业科学研究院项目(17226320D).

摘　　要：为研究中华金叶榆(Ulmus pumila‘Zhonghua Jinye’)幼苗在干旱胁迫下的生理响应及分子机制。试验采用盆栽中华金叶榆苗人工模拟控水法进行干旱胁迫处理(对照组、中度和重度干旱胁迫组的土壤含水量分别保持在田间含水量的80%、40%、20%),分别在胁迫0、10、20、30 d测定中华金叶榆的相对电导率、丙二醛含量、可溶性糖含量、可溶性蛋白含量以及光合指标,并在胁迫30 d时进行转录组测序分析。结果表明:随着干旱胁迫时间的延长,叶片的相对电导率、丙二醛含量、可溶性糖含量逐渐上升,净光合速率、蒸腾速率和气孔导度逐渐下降,可溶性蛋白含量先上升后下降,胞间CO_(2)浓度先下降后上升。GO功能注释发现,差异表达基因(DEGs)主要富集在分子功能中;KEGG富集分析显示,光合作用是中度胁迫特有的能量代谢通路,核糖体通路在重度胁迫下显著富集。中度、重度胁迫分别有661个、1945个DEGs,有179个共有DEGs。qRT-PCR验证表明,8个DEGs在不同程度胁迫中的表达情况与转录组分析的结果基本一致,证明转录组数据的可靠性。干旱胁迫下渗透调节物质的积累起到积极的抗旱作用,共有DEGs主要富集在光合作用、淀粉和蔗糖代谢、酪氨酸代谢、玉米素的生物合成、氨基糖和核苷酸糖代谢通路。This study analyzed the physiological response and molecular mechanism of Ulmus pumila‘Zhonghua Jinye’seedlings under drought stress.The soil water content of the the potted Ulmus pumila‘Zhonghua Jinye’seedlings were maintained at different levels to simulating drought stress.The leaves were collected after 0,10,20,and 30 days of stress to examine the relative conductivity,malondialdehyde content,soluble sugar content,soluble protein content,and photosynthetic index.The results showed that the relative conductivity,malondialdehyde content,and soluble sugar content of the leaves gradually increased with the extension of drought stress,while the net photosynthetic rate,transpiration rate and stomatal conductance gradually decreased.The soluble protein content first increased and then decreased that displayed an opposite trend of the intercellular CO_(2) concentration.Transcriptom analysis of the leaves after drought stress for 30 days identified drought response genes in molecular functions.KEGG enrichment analysis showed that the photosynthesis pathway was a unique energy metabolism pathway under moderate stress,and the ribosomal pathway was significantly enriched under severe stress.There were 661 DEGs and 1945 DEGs under mild and severe drought stress with 179 shared DEGs.It was founded that shared DEGs were mainly enriched in photosynthesis,starch and sucrose metabolism,tyrosine metabolism,zeatin biosynthesis,amino sugar and nucleotide sugar metabolism pathways.Verification of the expression by qRT-PCR showed that 8 DEGs displayed consistent expression with the transcriptom data,which proved the reliability of RNA-seq data.The accumulation of osmotic adjustment substances played a positive role in drought resistance.

关 键 词：中华金叶榆 干旱胁迫 生理响应 转录组分析 差异表达基因 

分 类 号：S792.19[农业科学—林木遗传育种]