褪黑素对低氮胁迫下油菜苗期氮吸收转运的影响  

Effect of melatonin on nitrogen absorption and transport of rapeseed at seedling stage under low nitrogen stress

作　　者：杨灵 韩配配 童佳峰 顾炽明 李银水[1] 代晶 谢立华[1] 秦璐[1] 廖星[1] YANG Ling;HAN Pei-pei;TONG Jia-feng;GU Chi-ming;LI Yin-shui;DAI Jing;XIE Li-hua;QIN Lu;LIAO Xing(Oil Crops Research Institute,Chinese Academy of Agricultural Sciences,Key Laboratory of Biology and Genetic Improvement of Oil Crops,Ministry of Agricultural and Rural Affairs,Wuhan 430062,China;Institute of Agricultural Sciences in Coastal Area of Jiangsu Province,Yancheng 224002,China)

机构地区：[1]中国农业科学院油料作物研究所/农业农村部油料作物生物学与遗传育种重点开放实验室,湖北武汉430062 [2]江苏沿海地区农业科学研究所,江苏盐城224002

出　　处：《中国油料作物学报》2023年第2期325-333,共9页Chinese Journal of Oil Crop Sciences

基　　金：国家绿肥产业技术体系(CARS-22);中国农业科学院科技创新工程(CAASASTIP-2013-OCRI)。

摘　　要：为提升油菜耐低氮胁迫能力,本研究探讨外源施用褪黑素(melatonine,MT)对低氮胁迫下苗期油菜生长及氮吸收转运的影响。通过砂培试验,研究不同氮处理下外源施用不同浓度MT对油菜苗期生物量、养分累积量和氮吸收转运相关基因(BnNRT2和BnAMT)表达的影响。结果表明,低氮胁迫下外源喷施MT显著提高油菜地上部和根系生物量,MT浓度为100μmol/L时,油菜干物质积累量的提升效果最佳;低氮胁迫下外源喷施MT增加油菜地上部和根系的氮累积量。进一步分析发现,当MT浓度为100μmol/L时,BnNRT2.1基因成员(除BnNRT2.1a)、BnNRT2.2a和BnNRT2.4b在根部的表达上调并达到最高,当MT浓度为50μmol/L时,BnNRT2.7和BnNRT2.5在新叶和老叶中的表达上调并达到最高;同时,外源施加MT后,BnAMT1.1a、BnAMT1.3b、BnAMT1.3c、BnAMT2.2a和BnAMT2.2c在新叶、老叶及根部的表达均显著上调,BnAMT1.4a、BnAMT1.4b、BnAMT2.1b、BnAMT2.2a和BnAMT2.2b在新叶和老叶的表达也显著上调,且除BnAMT1.3b和BnAMT1.3c外,上述基因均在MT 50μmol/L处理下表达最高。综上,外源喷施MT可能通过增强BnNRT2和BnAMT家族部分基因的表达,来提高低氮胁迫下油菜根系对氮的吸收,同时促进油菜根系有限的氮向地上部转运。因此,外源施用MT可以促进油菜对氮的吸收利用,缓解低氮胁迫,提升油菜耐低氮胁迫能力。In order to enhance the tolerance of rapeseed respond to low nitrogen(N)stress,this study investi⁃gated the effects of melatonin(MT)on N absorption and transport of rapeseed at the seedling stage under N defi⁃ciency conditions.The effects of exogenous application of MT on biomass,N uptake and accumulation,as well as the expressions of genes(BnNRT2s and BnAMTs)involved in N absorption and transport were analyzed by pot ex⁃periments.Results showed that,exogenous spraying of MT under N deficiency conditions significantly improved the shoots and roots biomass of rapeseed,especially when MT was sprayed at a concentration of 100μmol/L.And exoge⁃nous spraying of MT also significantly increased N accumulation of shoots and roots of rapeseed seedlings.Further analysis found that,expression levels of BnNRT2.1s gene members(except BnNRT2.1a),BnNRT2.2a,and Bn⁃NRT2.4b were up-regulated and reached the highest in roots when MT concentration was 100μmol/L.And Bn⁃NRT2.7s and BnNRT2.5s were up-regulated and reached the highest in leaves when MT concentration was 50μmol/L(MT50).Meanwhile,the expression of BnAMT1.1a,BnAMT1.3b,BnAMT1.3c,BnAMT2.2a and BnAMT2.2c genes were significantly up-regulated in junior leaves,senior leaves and roots after exogenous application of MT.The ex⁃pression of BnAMT1.4a,BnAMT1.4b,BnAMT2.1b,the abundance of BnAMT2.2a and BnAMT2.2b genes were also significantly enhanced in junior and senior leaves.Additionally,except BnAMT1.3b and BnAMT1.3c,all the above genes were expressed at the highest level under MT50 treatment.In conclusion,exogenous spraying of MT might im⁃prove N absorption and transport limited N to shoot through enhancing the expression of several BnNRT2s and BnAMTs.Thus exogenous application of MT could promote N absorption and utilization in rapeseed,alleviate low N stress and improve its low N tolerance.

关 键 词：油菜 低氮胁迫 褪黑素 氮吸收转运 

分 类 号：S565.4[农业科学—作物学]