高粱种子耐盐萌发的最佳引发水势及生理效应  

Optimal osmotic potential for salt tolerance germination of sorghum seeds and its physiological effects

作　　者：于文波 崔彤 邢艺凡 薄宇珊 陈小飞 刘畅 史晓龙 刘春娟 周宇飞[1] Yu Wenbo;Cui Tong;Xing Yifan;Bo Yushan;Chen Xiaofei;Liu Chang;Shi Xiaolong;Liu Chunjuan;Zhou Yufei(College of Agronomy,Shenyang Agricultural University,Shenyang 110866,China;Institute of Crops,Anhui Academy of Agricultural Sciences,Hefei 230001,China)

机构地区：[1]沈阳农业大学农学院,辽宁沈阳110866 [2]安徽省农业科学院作物所,安徽合肥230001

出　　处：《山西农业大学学报（自然科学版）》2024年第3期49-58,共10页Journal of Shanxi Agricultural University(Natural Science Edition)

基　　金：财政部和农业农村部国家现代农业产业技术体系建设专项(CARS-06-14.5-A17);辽宁省藏粮于技重大专项(2023JH1/10200001-03-01);辽宁省教育厅一般项目(LSNFW202006)。

摘　　要：[目的]盐胁迫是抑制高粱种子萌发的重要非生物胁迫因子之一,种子引发可以有效促进高粱种子在盐胁迫下的萌发,然而种子引发的最佳水势条件及其对萌发期生理调节的效应却少有研究。[方法]本试验以PEG-6000模拟不同的引发水势,在25℃下配置0(P1)、-0.3(P2)、-0.6(P3)、-0.9(P4)和-1.2 MPa(P5)共5个水势梯度,研究盐胁迫下(200 mmol·L^(-1) NaCl)引发高粱种子的萌发特征,采用主成分分析法鉴选最优种子引发水势条件,并探究其生理调控作用。[结果]盐胁迫下,P3引发的高粱种子发芽势、发芽指数、活力指数及根长、胚芽长、根干重、根鲜重、胚芽干重、胚芽鲜重均高于其它处理,且主成分分析综合因子得分最高,为最佳引发水势条件。与未引发种子相比,P3引发的高粱种子胚芽内相对含水量显著提升,相对电导率呈下降趋势,胚芽内K^(+)/Na^(+)和Ca^(2+)/Na^(+)显著上升(P<0.05)。同时,P3引发维持了盐胁迫下高粱种子萌发过程中线粒体结构的相对完整性,且线粒体内抗氧化酶超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性均有显著升高,表明P3引发增强了盐胁迫下胚芽内线粒体的抗氧化能力。[结论]-0.6 Mpa(P3)是盐胁迫下促进高粱种子萌发的最佳引发水势,可以有效减少盐胁迫引起的细胞膜损伤,保持了高粱种子胚芽线粒体结构的完整性,并提升了线粒体内抗氧化酶的活性,从而促进高粱种子耐盐萌发。[Objective]Salt stress is one of the important abiotic stress factors inhibiting the germination of sorghum seed.Seed prim-ing can effectively promote the germination of sorghum seeds under salt stress.However,there is limited research on the optimal priming osmotic potential conditions and their effect on physiological regulation during germination.[Method]In this experiment,different priming osmotic potentials were simulated using PEG-6000,including 0(P1),-0.3(P2),-0.6(P3),-0.9(P4)and-1.2 MPa(P5),under 25℃to study the germination characteristics of sorghum seeds under salt stress(200 mmol·L^(-1) NaCl).Principal component analysis was used to identify the optimal priming osmotic potential conditions and explore their physiologi-cal regulatory effects.[Result]Under salt stress,sorghum seeds primed with P3 showed higher germination vigor,germination index,vigor index,root length,shoot length,root dry weight,root fresh weight,shoot dry weight,and shoot fresh weight compared to other treatments.Additionally,the principal component analysis showed that P3 had the highest comprehensive factor score,indicating it as the optimal priming osmotic potential condition.Compared to unprimed seeds,sorghum seeds primed with P3 showed a significant increase in relative water content and a decrease in relative conductivity in the shoot.Fur-thermore,the K^(+)/Na^(+)and Ca^(2+)/Na^(+)ratio in the shoot increased significantly(P<0.05)under P3 priming.Moreover,prim-ing with P3 maintained the relative integrity of mitochondria during sorghum seed germination under salt stress.The activities of antioxidant enzymes such as Superoxide dismutase(SOD),Peroxidase(POD),Catalase(CAT)and Ascorbate peroxidase(APX)in mitochondria were significantly increased,indicating that priming with P3 enhanced the antioxidant capacity of mito-chondria during sorghum seed germination under salt stress.[Conclusion]-0.6 Mpa(P3)was the optimal osmotic potential for promoting the germination of sorghum seeds under salt stress.It can effectively reduce the cel

关 键 词：高粱 种子引发 萌发 水势 盐胁迫 抗氧化代谢 

分 类 号：S514[农业科学—作物学]