大豆根系天冬氨酸分解代谢对低氮低磷胁迫的应答  

Response of Aspartic Acid Catabolism in Soybean Roots to Low Nitrogen and Low Phosphorus Stress

作　　者：孙铭泽 杨光[1] 刘子君 刘美玲 谷勇哲 敖雪[1] SUN Mingze;YANG Guang;LIU Zijun;LIU Meiling;GU Yongzhe;AO Xue(Agronomy College of Shenyang Agriculture University,Shenyang 110866,China;Institute of Crop Science,Chinese Academy of Agricultural Sciences,Beijing 100081,China)

机构地区：[1]沈阳农业大学农学院,辽宁沈阳110866 [2]中国农业科学院作物科学研究所,北京100081

出　　处：《大豆科学》2025年第1期72-83,共12页Soybean Science

基　　金：中国-乌拉圭大豆研究与创新“一带一路”联合实验室建设与联合研究-03(2022YFE0203300-03);国家自然科学基金(31872854);沈阳市科学技术计划项目(No.23-410-2-09)。

摘　　要：天冬氨酸分解代谢途径产生了多种必需氨基酸,该途径也是植物体内各种氨基酸代谢的关键途径。氮和磷是限制大豆根系发育和代谢的重要元素,为探究大豆根系天冬氨酸代谢对低氮低磷胁迫的响应机制,以不同磷效率大豆品种为试验材料,采用砂培试验,设置不同氮磷培养处理,分析大豆根系天冬氨酸分解代谢途径在低氮和低磷条件下的变化情况,包括相关代谢产物的积累、氨基酸含量和相关酶活性及GmAK1基因表达量的变化。设置两个磷处理:常磷处理(P+,0.5 mmol·L^(-1))和低磷处理(P-,0.005 mmol·L^(-1))。设置两个氮处理:常氮处理(N+,2 mmol·L^(-1))和低氮处理(N-,0.2 mmol·L^(-1))。结果表明:与常磷常氮(P+N+)条件相比,常磷低氮(P+N-)胁迫处理使大豆根系氮磷积累量下降了11.63%~44.89%,低磷常氮(P-N+)胁迫使其降低了14.80%~46.89%,P-N+胁迫对大豆根系氮磷积累量造成的影响更为显著。大豆根系天冬氨酸激酶(AK)活性在各个时期都显著高于天冬氨酸转氨酶(AST)和天冬酰胺合成酶(ASNS)。在V2期,低磷低氮(P-N-)胁迫使磷高效大豆品种辽豆13根系的ASNS活性显著提高10.86%,P+N-胁迫使磷低效大豆铁丰3号根系的AK活性显著提高5.21%;在R^(2)期,P-N-胁迫使铁丰3号根系的ASNS活性显著提高了8.84%;在R6期,3种酶活性在不同处理下变化范围较小。所测氨基酸含量中,除蛋氨酸(Met)外,其余氨基酸均对P-N+胁迫反应明显,且苗期最显著。此外,两个品种大豆根系AK酶编码基因GmAK1的表达量受P-N+胁迫影响更为明显,其中,P-N+胁迫使磷高效大豆辽豆13根系GmAK1的表达量在R^(2)期显著增加了77.92%,使磷低效大豆铁丰3号显著降低了89.61%。研究阐明了低磷胁迫较低氮胁迫对大豆根系天冬氨酸分解代谢途径具有更为显著的影响,且苗期表现最为明显,为低氮和低磷条件影响大豆根系的研究提供新思路。The metabolic pattway of aspartic acid decomposition produces multiple essential amino acids,which is also a key pathway for the metabolism of various amino acids in plants.Nitrogen and phosphorus are important elements that restrict the development and metabolism of soybean roots.In order to explore the response mechanism of soybean root aspartic acid metabolism to low nitrogen and low phosphorus stress,soybean varieties with different phosphorus efficiency were used as experimental materials,sand culture tests were conducted,and different nitrogen and phosphorus culture treatments were set up to analyze the changes of the aspartic acid catabolism pathway of soybean roots under low nitrogen and low phosphorus conditions.Including the accumulation of related metabolites,changes in amino acid content and related enzyme activity,and the change of GmAK1 gene expression.There were two phosphorus treatments,normal phosphorus treatment(P+,0.5 mmol·L^(-1))and low phosphorus treatment(P-,0.005 mmol·L^(-1)).And there were two nitrogen treatments,normal nitrogen treatment(N+,2 mmol·L^(-1))and low nitrogen treatment(N-,0.2 mmol·L^(-1)).The results showed that P+N-stress reduced root nitrogen and phosphorus accumulation by 11.63%to 44.89%compared with P+N+condition,and P-N+stress reduced root nitrogen and phosphorus accumulation by 14.80%to 46.89%.The effect of P-N+stress on root nitrogen and phosphorus accumulation was more significant.The activity of aspartate kinase(AK)in soybean root was significantly higher than that of aspartate aminotransferase(AST)and aspartate synthetase(ASNS)at all stages.In V2 stage,low phosphorus and low nitrogen(P-N-)stress significantly increased ASNS activity in the roots of P-efficient soybean variety Liaodou 13 by 10.86%,while P+N-stress significantly increased AK activity in the roots of P-inefficient soybean variety Tiefeng 3 by 5.21%.In R^(2) stage,P-N-stress significantly increased the root ASNS activity of Tiefeng 3 varieties by 8.84%.In the R6 stage,the activity of the three enzyme

关 键 词：大豆根系 低氮 低磷 氨基酸代谢 天冬氨酸分解代谢 酶活性 

分 类 号：S565.1[农业科学—作物学]