不同耐盐型玉米幼苗抵御盐胁迫的途径及差异基因表达  

Pathways and differential gene expression in salt-tolerant and salt-sensitive maize seedlings under salt stress

作　　者：刘威帆 屈小玉 刘昊 万猛虎 马风兰 崔永 马小英 李涛[1] 黄霖锋 吴娜[1] 刘吉利[2] LIU Wei-fan;QU Xiao-yu;LIU Hao;WAN Meng-hu;MA Feng-lan;CUI Yong;MA Xiao-ying;LI Tao;HUANG Lin-feng;WU Na;LIU Ji-li(College of Agriculture,Ningxia University,Yinchuan,Ningxia 750021,China;College of Ecology and Environment,Ningxia University,Yinchuan,Ningxia 750021,China)

机构地区：[1]宁夏大学农学院,宁夏银川750021 [2]宁夏大学生态环境学院,宁夏银川750021

出　　处：《植物营养与肥料学报》2025年第4期730-744,共15页Journal of Plant Nutrition and Fertilizers

基　　金：国家重点研发计划项目(2021YFD1900603);宁夏大学研究生创新项目(CXXM202428)。

摘　　要：【目的】玉米幼苗通过一系列生理生化机制抵御盐胁迫带来的危害,我们研究了不同耐盐型玉米品种抵御盐胁迫的代谢途径及主要差异化基因表达,为玉米育种提供基因靶点。【方法】采用蛭石和珍珠岩1∶1混合基质进行盆栽试验,供试材料为盐敏感型玉米品种先玉335和耐盐型玉米品种DK815。当玉米幼苗长至6片叶时,分别浇灌NaCl添加浓度为0 mmol/L(CK)和240 mmol/L(ST)的营养液,处理24 h后,取第5片叶片样品,采用便携式光合系统测定仪LI-6400XT测定光合指标,用Elisa酶联免疫试剂盒测定该叶片脱落酸(ABA)、生长素(IAA)、赤霉素(GA)和茉莉酸(JA)含量,并进行转录组测序分析。【结果】与CK相比,盐胁迫显著降低了先玉335和DK815的光合参数气孔导度(Gs)、净光合速率(Pn)和蒸腾速率(Tr),但未降低胞间CO_(2)浓度(Ci)。同时,盐胁迫显著降低了生长促进激素IAA和GA含量,提高了胁迫反应激素ABA和JA含量。其中,DK815的光合参数(Pn、Tr、Gs)和激素(IAA、GA、JA)的变化幅度均小于先玉335。转录组分析显示,受到盐胁迫后先玉335和DK815的上调基因分别为2500和2251个,下调基因分别为2537和2466个。先玉335和DK815在基因表达和功能富集上表现出显著差异。GO和KEGG富集分析显示,先玉335的差异基因主要涉及核糖体生物发生、蛋白质合成、能量代谢、氨基酸代谢、DNA修复、抗氧化和过氧化物酶体途径,而DK815的差异基因则与RNA修饰、细胞周期、细胞壁生物发生、氨基酸代谢、核酸代谢、物质运输、结构物质合成和光合作用相关。盐胁迫下,淀粉和蔗糖代谢途径中淀粉和海藻糖合成基因(glgC、glgA、WAXY、TPS、ostB)下调,淀粉和纤维素降解基因(AMY、malZ、bglB、EG)上调,且DK815的淀粉和纤维素降解基因上调幅度显著高于先玉335。此外,两品种还通过调节激素信号通路关键基因(ARF、AUX/IAA、SAUR、ARRA、PP2C、SnRK2)适应盐�【Objectives】Maize seedlings employ a series of physiological and biochemical mechanisms to resist salt stress-induced damage.We investigated the metabolic pathways and major differential gene expressions of different salt-tolerant maize varieties in order to provide gene targets for maize breeding.【Methods】A pot experiment was conducted using a 1∶1 mixture of vermiculite and perlite as the substrate.The test materials were Xianyu 335(salt-sensitive type)and DK815(salt-tolerant type).At the 6-leaf stage,maize seedlings were irrigated with nutrient solutions containing 0 mmol/L(CK)or 240 mmol/L NaCl(ST),and the 5th leaf samples were collected after one day of salt treatment.A portable photosynthesis system LI-6400XT was used to measure photosynthetic parameters.ELISA kits were used to determine the abscisic acid(ABA),auxin(IAA),gibberellin(GA),and jasmonic acid(JA)contents.The transcriptome sequencing analysis of the leaf samples was also performed to clearify the differentiable expression genes.【Results】Compared with CK,salt stress significantly decreased the stomatal conductance(Gs),net photosynthetic rate(Pn)and transpiration rate(Tr)of Xianyu 335 and DK815,but did not decrease intercellular CO_(2) concentration(Ci).Salt stress significantly decreased the contents of growth promoting hormones IAA and GA,and significantly increased the contents of stress response hormones ABA and JA.DK815 was examined smaller variations of photosynthetic parameters(Pn,Tr,Gs)and hormones(IAA,GA,JA)than Xianyu 335.Salt stress resulted 2500 and 2251 up-regulated genes and 2537 and 2466 down-regulated genes in Xianyu 335 and DK815,respectively.The differential genes of Xianyu 335 were mainly involved in ribosome biogenesis,protein synthesis,energy metabolism,amino acid metabolism,DNA repair,antioxidant and peroxisome pathways.While the differential genes of DK815 were associated with RNA modification,cell cycling,cell wall biogenesis,amino acid metabolism,nucleic acid metabolism,material transport,structural substance s

关 键 词：盐胁迫 玉米 光合作用 转录组 植物激素信号 淀粉与蔗糖代谢 

分 类 号：S513[农业科学—作物学]