青檀扦插苗对不同氮素水平的形态、光合生理响应和转录组分析  

Morphological,photosynthetic physiological and transcriptome analyses of Pteroceltis tatarinowii in response to different nitrogen application levels

作　　者：郭伟 韩秀 张利 王迎[1] 杜辉[1] 燕语 孙忠奎 张林[1] 李国华[1] 罗磊[1] GUO Wei;HAN Xiu;ZHANG Li;WANG Ying;DU Hui;YAN Yu;SUN Zhongkui;ZHANG Lin;LI Guohua;LUO Lei(Taishan Academy of Forestry Sciences,Tai’an 271000,China;College of Agricultural and Biological Engineering,Heze University,Heze 274015,China;Tai’an Time Garden Technology Development Co.,Ltd,Tai’an,271000,China)

机构地区：[1]泰安市泰山林业科学研究院,山东泰安271000 [2]菏泽学院农业与生物工程学院,山东菏泽274015 [3]泰安时代园林科技开发有限公司,山东泰安271000

出　　处：《南京林业大学学报（自然科学版）》2023年第5期87-96,共10页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：泰安市乡土观赏树种国家林木种质资源库项目(林场发[2016]153号);泰安市科技发展计划(引导计划)(2018NS0090)。

摘　　要：【目的】研究不同氮素水平下青檀(Pteroceltis tatarinowii)形态和光合生理变化,筛选氮素响应基因,为后期深入开展氮素响应分子机理研究提供参考。【方法】选取0、2、50 mmol/L NH_(4)NO_(3)的Hocking’s营养液分别作为缺氮(N_(0))、中氮(N_(2))、高氮(N_(50))处理条件对青檀扦插苗进行盆栽控制试验,28 d时进行形态和光合生理指标测定。对不同氮素水平处理后的青檀混合样本进行3代全长转录组测序,测序结果为2代转录组测序提供参考,通过生物信息学分析筛选不同氮素水平响应的差异表达基因并进行KEGG通路富集分析,利用荧光定量PCR技术对富集基因进行根和叶片中的表达分析。【结果】氮素处理第28天时青檀的株高、地径、叶片数量、叶面积、比叶面积、叶片生物量、茎生物量,以及根系、叶片与茎氮含量随着氮素处理浓度提高而提高,总根长、总根表面积、总根体积、比根长、根冠比、根系生物量随着氮素浓度提高而降低。高氮素处理明显提高了叶绿素a、叶绿素b、类胡萝卜素含量,增强了净光合速率和气孔导度。不同氮素水平的转录组测序的差异表达基因中76个基因随着氮素水平提高稳定上调表达,32个基因随着氮素水平提高稳定下调表达。对这108个基因进行KEGG通路富集分析发现排在前两位的分别是光合作用和氮代谢通路,光合作用通路富集的基因是OEE2、OEE3、PSBR、PSB27、PSAF和PSAK,氮代谢通路富集的基因是2个NR和1个NiR基因。表达分析结果显示这9个基因在根和叶片中具有相似的表达模式,缺氮处理中表达量最低,高氮处理中表达量最高;光合作用通路的6个基因在每一种氮素浓度处理时在叶中的表达量均高于在根中的。【结论】随着氮素浓度的提高,光合作用通路基因表达上调,促进了光合作用,硝酸还原酶基因和亚硝酸还原酶基因表达上调,提高了硝酸根的同�【Objective】Our objectives are to study the morphological and photosynthetic physiological changes of Pteroceltis tatarinowii under different nitrogen application levels,and screen nitrogen response related genes in order to provide reference for further research on the molecular mechanisms how nitrogen application trigger changes in P.tatarinowii.【Method】A pot experiment was conducted with the cuttings of P.tatarinowii fertilized with Hocking’s complete nutrient solution with 0(limiting,N_(0)),2(intermediate,N_(2))and 50 mmol/L(luxuriant,N_(50))NH_(4)NO_(3),respectively.The physiological and photosynthetic morphological parameters were determined at day 28.SMRT-seq,performed with the pooled sample of P.tatarinowii treated with different nitrogen application levels,provided full length transcriptome data as a reference for the RNA-seq.Differentially expressed genes responding to different nitrogen levels were screened using bioinformatics methods.Then,the KEGG pathway enrichment analysis was conducted.The expression of the differentially expressed genes enriched in roots and leaves was quantified by RT-qPCR.【Result】The physiological and morphological observations,determined at day 28 after being fertilized with different nitrogen application levels,showed that the values of height,stem diameter,number of leaves,leaf area,specific leaf area,biomass of leaves,biomass of stems,N concentration in roots,leaves and stems increased with the increase of nitrogen concentration,while the values of the total root length,total root surface area,total root volume,specific root length,root to shoot ratio,and biomass of roots,all decreased with the increase of nitrogen concentration.The chlorophyll a,chlorophyll b,carotenoid content,net photosynthetic rates and stomatal conductance were significantly promoted by the luxuriant nitrogen level.Of the differentially expressed genes among different nitrogen levels based on the global transcriptomic profiling by RNA-seq,76 genes were up-regulated following the increase o

关 键 词：青檀 氮素 形态和光合生理响应 全长转录组 差异表达基因 

分 类 号：S722.5[农业科学—林木遗传育种]