胞外多糖对盐胁迫下荆芥种子萌发、幼苗生长及生理特性的影响  

Effects of Extracellular Polysaccharides on Seed Germination,Seedling Growth and Physiological Characteristics of Schizonepeta tenuifolia under Salt Stress

作　　者：唐茜[1] 王佳丽 李文强 TANG Qian;WANG Jiali;LI Wenqiang(College of Architecture and Design,Chongqing College of Humanities,Science and Technology,Chongqing 400715,China;College of Horticulture and Landscape Architecture,Southwest University,Chongqing 400715,China)

机构地区：[1]重庆人文科技学院建筑与设计学院,重庆400524 [2]西南大学园艺园林学院,重庆400715

出　　处：《河南农业科学》2024年第10期96-105,共10页Journal of Henan Agricultural Sciences

基　　金：重庆人文科技学院校级科研项目(CRKZK2022005);重庆市教育科学规划项目(2020-GX-344)。

摘　　要：为提高盐渍地中荆芥的种植效益,探究植物乳杆菌(Lactobacillus plantarum)胞外多糖对盐胁迫下荆芥种子萌发、幼苗生长的影响,同时从幼苗根系生理特性上分析其具体作用机制,设置6个处理[空白对照组(CK1)、盐胁迫对照组(CK2)、50 mg/kg胞外多糖组(T1)、100 mg/kg胞外多糖组(T2)、200 mg/kg胞外多糖组(T3)、400 mg/kg胞外多糖组(T4)]进行试验。结果表明,胞外多糖对荆芥种子萌发和幼苗生长具有显著的促进作用。其中,添加200 mg/kg胞外多糖(T3)效果最显著,与CK2相比,其种子发芽率、发芽势、发芽指数和活力指数分别显著增加76.13%、144.16%、137.45%、265.28%,幼苗株高、茎粗、地下干质量和地上干质量分别显著升高60.49%、14.73%、40.08%、85.39%,脯氨酸、可溶性蛋白、可溶性糖含量分别提高21.02%、84.56%、40.02%,Na+含量降低54.63%,K+含量升高95.24%,Na+/K+值降低76.76%,根系电解质渗出率、丙二醛(MDA)含量分别降低44.54%、43.24%,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性分别显著提高30.39%、34.59%、24.31%。综上所述,植物乳杆菌胞外多糖可以通过根系渗透调节和激活抗氧化酶防御系统来提高幼苗的抗盐性,进而促进荆芥种子萌发和幼苗生长。In order to improve the planting efficiency of Schizonepeta tenuifolia in saline soil,the effects of extracellular polysaccharides from Lactobacillus plantarum on seed germination and seedling growth under salt stress were explored,and the specific mechanism was analyzed from the physiological characteristics of seedling roots.Six treatments were set up:blank control group(CK1),salt stress control group(CK2),50 mg/kg extracellular polysaccharide group(T1),100 mg/kg extracellular polysaccharide group(T2),200 mg/kg extracellular polysaccharide group(T3),and 400 mg/kg extracellular polysaccharide group(T4).The results showed that extracellular polysaccharides significantly promoted the seed germination and seedling growth of Schizonepeta tenuifolia.Among them,the effect of adding 200 mg/kg extracellular polysaccharide(T3)was the most significant.Compared with CK2,the seed germination rate,germination potential,germination index and vigor index were significantly increased by 76.13%,144.16%,137.45%and 265.28%,respectively.The plant height,stem diameter,underground dry weight and aboveground dry weight of seedlings were significantly increased by 60.49%,14.73%,40.08%and 85.39%,respectively.The contents of proline,soluble protein and soluble sugar were increased by 21.02%,84.56%and 40.02%,respectively.The content of Na+was decreased by 54.63%,the K+content was increased by 95.24%,and the Na+/K+value decreased by 76.76%.The root electrolyte leakage rate and malondialdehyde(MDA)content decreased by 44.54%and 43.24%,respectively,and the activities of superoxide dismutase(SOD),catalase(CAT),and peroxidase(POD)increased by 30.39%,34.59%and 24.31%,respectively.In summary,the extracellular polysaccharides of Lactobacillus plantarum can improve the salt resistance of seedlings through root osmotic regulation and activation of antioxidant enzyme defense system,thereby promoting seed germination and seedling growth of Schizonepeta tenuifolia.

关 键 词：荆芥 植物乳杆菌 胞外多糖 种子萌发 幼苗生长 生理特性 

分 类 号：S451[农业科学—植物保护] S512.301