柳枝稷生长、生理和基因差异表达对供磷水平的响应  

Response of growth,physiology and differential gene expression to phosphate supply level in switchgrass(Panicum virgatum L.)

作　　者：刘威帆 赵匆 吴娜[1] 刘吉利[2] LIU Wei-fan;ZHAO Cong;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》2024年第11期2181-2196,共16页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金项目(31860344);宁夏自然科学基金项目(2022AAC03062)。

摘　　要：【目的】探究柳枝稷(Panicum virgatum L.)在不同磷水平下的生理代谢及转录水平变化,以解析柳枝稷磷响应特征,挖掘磷高效利用基因。【方法】以‘Pathfinder’品种柳枝稷为供试材料,采用水培方法(Hoagland营养液)进行培养试验。营养液设置4个KH_(2)PO_(4)供应水平:20、100、200、500μmol/L(分别记为P20、P100、P200、P500)。在生长箱中培养45天后,取样测定柳枝稷生长和根系表型指标、抗逆酶活性,并进行叶片和根系转录组测序,分析不同磷水平下柳枝稷叶片和根系的响应差异。最后,从糖酵解和苯丙素生物合成途径挑选了部分基因进行qRT-PCR分析,以证实转录组测序的准确性。【结果】随着供磷水平的提高,叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性呈先降低后增加的趋势;根系总长度、根系总面积和根系活力呈先增加后减少的趋势;叶片和根系中酸性磷酸酶活性和磷含量呈先增加后减少的趋势。不同供磷浓度下,叶片和根系中各磷处理共同表达差异表达基因(DEGs)分别有1091、1762个。GO富集注释显示,叶片中DEGs富集在离子跨膜转运、氧化还原酶上,根系则富集在特异DNA序列结合、主动跨膜转运和裂合酶上。两器官共同富集的DEGs主要定位于抗氧化酶、转移酶、无机分子跨膜转运蛋白上。KEGG富集分析发现,柳枝稷叶片和根系中共有9个共同代谢通路,其中氨基糖和核苷糖代谢、糖酵解/糖异生、苯丙素生物合成、蔗糖和淀粉代谢通路DEGs显著富集,具体为:糖酵解和苯丙素生物合成途径各有16个DEGs,涉及磷吸收转运基因共20个。糖酵解途径中关键酶基因(AE、PGM、HK、PFK),苯丙素生物合成途径中关键酶基因(PAL、CCR、CAD、C4H、4CL)和磷吸收转运调控基因(GPT2、PHT2;1、TPT、PPT1、PPT2、PPT3、PiC3、APC2)的差异化表达,引起柳枝稷叶片和根系对磷营养的代谢反应差异。【结�【Objectives】We explored the physiological metabolism and transcriptional changes of switchgrass(Panicum virgatum L.)under different phosphorus levels,aiming to understand the phosphorus response of root morphology and growth of switchgrass.【Methods】A hydroponics experiment of switchgrass was carried out,based on the Hoagland nutrient solution,4 KH_(2)PO_(4) supply levels:20,100,200,500μmol/L were setup(recorded as P20,P100,P200,P500).After 45 days of treatment,the seedlings were harvested for determination of physiological,root phenotype indexes and antistress enzyme activities,and transcriptome sequencing of leaves and roots was performed to identify the differentially expressed genes(DEGs)in leaves and roots.Some high expressed DEGs from glycolysis and phenylpropyl biosynthesis pathways were selected for qRT-PCR analysis to confirm the accuracy of transcriptome sequencing.【Results】With the increase of P supply level,the activities of SOD,POD,and CAT in the leaves showed a trend of initially decreasing and then increasing;the total length,total area,and vitality of the roots increased first and then decreased;the acid phosphatase activities and phosphorus contents in both leaves and roots showed an initial increase followed by a decrease trend.There were 1091 and 1762 commonly expressed genes in the leaves and roots under all the phosphorus levels.GO enrichment annotation showed that the DEGs in leaves were mainly enriched in ion transmembrane transport and oxidoreductase,and the DEGs in roots were mainly enriched in specific DNA sequence binding,active transmembrane transport and lyase,and the DEGs in both the two organs in antioxidant enzyme,transferase and inorganic molecular transmembrane transporter.KEGG enrichment analysis showed that there were 9 common metabolic pathways in switchgrass leaves and roots,the DEGs were significantly enriched in amino sugar and nucleoside glucose metabolism,glycolysis/gluconeogenesis,phenylpropanoid biosynthesis,sucrose and starch metabolism pathways,and both gl

关 键 词：供磷水平 柳枝稷 生理指标 转录组 糖酵解 苯丙素生物合成 磷吸收转运 

分 类 号：S578[农业科学—作物学]