γ-氨基丁酸(GABA)种子引发缓解辣椒盐胁迫的效果及生理生化的变化  

Effects of GABA seed priming on alleviating salt stress and physiological and biochemical changes in Capsicum annuum

作　　者：林欣琪 魏茜雅 梁腊梅 秦中维 李映志[1] LIN Xinqi;WEI Qianya;LIANG Lamei;QIN Zhongwei;LI Yingzhi(College of Coastal Agricultural Sciences,Guangdong Ocean University,Zhanjiang 524088,Guangdong,China)

机构地区：[1]广东海洋大学滨海农业学院,广东湛江524088

出　　处：《广西植物》2023年第12期2338-2351,共14页Guihaia

基　　金：广东省科技厅科技计划项目(2016A020210116,2012A020602051);广东海洋大学创新强校项目(GDOU2013050217,GDOU2016050256)。

摘　　要：种子引发是提高作物生长期耐盐性的有效方法,而γ-氨基丁酸(GABA)种子引发对辣椒(Capsicum annuum)耐盐性的效果和作用机制尚不清楚。该研究以‘茂蔬360’朝天椒为材料,分析了不同浓度γ-氨基丁酸(0、1.0、2.0、4.0、6.0、8.0μmol·L^(-1))种子引发对4~6叶期100 mmol·L^(-1) NaCl胁迫下的植株生物量、渗透调节物质、抗氧化能力、光合作用系统及钾钠离子吸收的影响。结果表明:(1)种子引发能显著增加盐胁迫下辣椒植株的生物量,以6.0μmol·L^(-1) GABA引发处理的效果最佳。(2)种子引发处理增加盐胁迫下植株可溶性糖、可溶性蛋白、脯氨酸的含量,同时,O_(2)^(-)和MDA的含量下降,抗氧化酶(SOD、POD、CAT和APX)活性增强,叶片叶绿素含量增加,叶片叶绿素荧光参数受胁迫影响程度低,叶绿素荧光指标包括F_(v)′/F_(m)′、qP_Lss、QY_Lss、NPQ_Lss和Rfd均有所上升。根、茎中的K^(+)含量和K^(+)/Na^(+)比值下降。(3)灰色关联度分析表明,GABA种子引发主要通过提高POD、CAT的活性和渗透调节物质含量来缓解盐胁迫对辣椒植株的伤害。综上所述,6.0μmol·L^(-1) GABA种子引发可有效提高辣椒苗期的耐盐性,其作用机制可能是提高了盐胁迫下辣椒植株的抗氧化能力和渗透调节能力。Seed priming is proved to be an efficient way to improve crop salt tolerance,which is a measure of pre-treating seed with various agents while obtaining enhancement to crop performance at growing stage.Gamma amino butyric acid(GABA) is a non-protein amino acid involved in various metabolic processes,and partially protects plants from environmental stress.Enhancing effects of GABA priming on germination characteristics and abiotic stress have been established in several crops.However,the effect and mechanism of GABA seed priming on salt tolerance of pepper(Capsicum annuum) are still unknown.In this study,a hybrid pepper variety of ‘Maoshu 360' Chaotian pepper was used as material,the effects of seed priming with various concentrations of GABA(0,1.0,2.0,4.0,6.0,8.0 μmol·L~(-1)) on plant biomass,leaf osmotic regulating substance,leaf antioxidant capacity,leaf photosynthesis system,potassium and sodium ion uptake and distribution between leaves and shoots of pepper plants under 100 mmol·L~(-1) NaCl stress applied at 4-6 leaf stage were investigated.The results were as follows:(1) From the point of plant growth under salt stress,the best concentration of GABA for seed priming of pepper was 6.0 μmol·L~(-1),which greatly boosted the biomass of pepper plants under salt stress.(2) The mechanisms of GABA seed priming promoting salt tolerance of pepper were further analyzed.Seed priming increased the leaf contents of soluble sugar,soluble protein,chlorophyll and proline,decreased the leaf contents of O_2~- and malondialdehyde(MDA),enhanced the leaf activities of antioxidant enzymes,including super oxide dismutase(SOD),peroxidase(POD),catalase(CAT) and ascorbate peroxidase(APX),and raised several chlorophyll fluorescence metrics,including F_v′/F_m′,qP_Lss,QY_Lss,NPQ_Lss and Rfd,reduced the K~+ content and K~+/Na~+ ratio in roots and stems.(3) For a comprehensive understanding of the mechanisms of GABA seed priming promoting salt tolerance of pepper,grey correlation analysis was carried out.Based on results of grey

关 键 词：γ-氨基丁酸(GABA) 辣椒 种子引发 耐盐性 灰色关联度分析 

分 类 号：Q945[生物学—植物学]