外源褪黑素对镉胁迫下棉花种子萌发、抗氧化酶活性及渗透调节物质含量的影响  

Effects of exogenous melatonin on germination,antioxidant enzymes activity,and osmotic adjustment substance content of cotton seed under cadmium stress

作　　者：马鑫颖 宋晨 孟妍君 刘连涛[2] 张科 张永江[2] 孙红春[2] 白志英[1,2] 李存东 Ma Xinying;Song Chen;Meng Yanjun;Liu Liantao;Zhang Ke;Zhang Yongjiang;Sun Hongchun;Bai Zhiying;Li Cundong(College of Life Science,Hebei Agricultural University,Baoding,Hebei 071000,China;College of Agronomy,Hebei Agricultural University/State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Crop Growth Regulation of Hebei Province,Baoding,Hebei 071000,China)

机构地区：[1]河北农业大学生命科学学院,河北保定071000 [2]河北农业大学农学院/华北作物改良与调控国家重点实验室/河北省作物生长调控重点实验室,河北保定071000

出　　处：《棉花学报》2023年第4期313-324,共12页Cotton Science

基　　金：河北省自然科学基金(C2022204036);河北省重点研发计划项目(20326409D);华北作物改良与调控国家重点实验室自主研究课题(NCCIR2020ZZ-18);河北省现代棉花产业技术体系(HBCT2023070207)。

摘　　要：【目的】镉(cadmium,Cd)是严重的环境污染物之一,Cd胁迫影响种子萌发。褪黑素(melatonin,MT)作为1种抗氧化剂,能够促进种子萌发。本研究通过分析外源MT对Cd胁迫下棉花种子萌发性状、抗氧化酶活性以及渗透调节物质含量的影响,明确MT对Cd胁迫下棉花种子萌发的调控效应。【方法】试验以转基因抗虫棉农大棉601种子为材料,筛选出Cd胁迫浓度(100μmol·L^(-1))以及MT浓度(50μmol·L^(-1)),设置4个处理CK(纯水对照)、MT(褪黑素)、Cd(镉胁迫)、CM(镉胁迫+褪黑素),研究了不同处理下棉花种子的发芽势、发芽率、幼苗生物量以及抗氧化酶活性、渗透调节物质含量。【结果】100μmol·L^(-1)Cd胁迫下棉花种子的发芽势、发芽率、胚根和胚芽长度以及胚根生物量显著降低,但对胚芽生物量没有显著影响;Cd胁迫下棉花种子中超氧化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)、过氧化氢酶(catalase,CAT)活性降低,可溶性蛋白含量降低,脯氨酸、可溶性糖含量、丙二醛含量升高。施用50μmol·L^(-1)MT提高了Cd胁迫下棉花种子的发芽势和发芽率,提高了种子中SOD、POD、CAT活性,提高了可溶性蛋白、可溶性糖、脯氨酸含量,降低了丙二醛含量,显著提高了胚根和胚芽长度以及胚根的生物量。【结论】施加50μmol·L^(-1)MT能够有效缓解100μmol·L^(-1)Cd胁迫对棉花种子萌发的抑制作用。[Objective]Cadmium(Cd)is one of the serious environmental pollutants,and Cd stress affects seed germination.Melatonin(MT),as an antioxidant,and can promotes seed germination.In this study,the effects of MT on cotton seed germination,antioxidant activity,and osmotic adjustment content under Cd stress were analyzed to clarify the regulatory effect of MT on cotton seed germination under Cd stress.[Method]Seeds of the transgenic insect-resistant cotton variety Nongdamian 601 were used as material,Cd concentration and MT concentration were screened.And four treatments,CK(control,water),MT(melatonin treatment,50μmol·L^(-1)),Cd(cadmium stress 100μmol·L^(-1)treatment),CM(cadmium+melatonin treatment)were set.The germination potential,germination rate,seedling biomass,antioxidant enzyme activity,and osmotic adjustment content of cotton seed under different treatments were studied.[Result]Cd stress of 100μmol·L^(-1)significantly decreased the germination potential,the germination rate,the length of radicle and plumule,the fresh and dry mass of radicle,but had no significant effect on the fresh or dry mass of plumule.Under the stress of Cd,the activity of superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),and soluble protein content of cotton seed were decreased.The content of proline,soluble sugar and malondialdehyde(MDA)were increased.Application of MT(50μmol·L^(-1))increased the germination potential and germination rate of cotton seed under Cd stress,the activity of SOD,POD and CAT,the content of soluble protein,soluble sugar and proline,while decreased the content of MDA,significantly increased the length of radicle and plumule,and significantly increased radicle biomass.[Conclusion]Exogenous MT(50μmol·L^(-1))could effectively alleviate the inhibitory effeet of Cd stress(100μmol·L^(-1))on cotton seed germination.

关 键 词：棉花 褪黑素 镉 萌发 抗氧化酶 渗透调节物质 

分 类 号：S562[农业科学—作物学]