GABA和CaCl_(2)复配对盐碱胁迫下番茄幼苗生长、叶绿素荧光参数和活性氧的影响

Effects of GABA and CaCl_(2) Compound on Growth,Chlorophyll Fluorescence Parameters and Reactive Oxygen of Tomato Seedlings under Salt and Alkali Stress

γ-氨基丁酸(GABA)对增强作物抗逆性发挥了重要的作用,而内源GABA的合成与胞内Ca^(2+)浓度相关。本试验以盐敏感型番茄品种中杂9号为试材,采用表型差异显著的盐碱胁迫浓度(60 mmol·L^(-1)NaCl+60 mmol·L^(-1)NaHCO_3),研究单独添加GABA和CaCl_(2)及两者复配组合对盐碱胁迫下番茄幼苗生长、叶绿素荧光和活性氧等指标的影响。结果表明:外源GABA和CaCl_(2)单独处理和复配处理均可提高盐碱胁迫下番茄的株高、茎粗、根长、根数生长速率,且幼苗鲜质量和干质量也明显上升;叶色指数显著提高,叶绿素荧光参数也得到明显改善;同时,外源GABA和CaCl_(2)单独处理和复配处理还降低了盐碱胁迫下番茄叶片活性氧的积累。与单独处理相比,复配处理SA+Ca6+GABA5对于盐碱胁迫伤害的缓解效果更好,说明外源CaCl_(2)的添加对于GABA增强植物耐盐碱能力有促进作用。

Gamma amino butyric acid(GABA)plays an important role in enhancing plants stress resistance.While,the synthesis of endogenous GABA is related to the concentration of intracellular Ca^(2+).Taking the salt sensitive tomato variety‘Zhongza No.9’as test material,and adopting salt alkali stress concentration(60 mmol·L^(-1) NaCl+60 mmol·L^(-1) NaHCO3)with remarkable different phenotype,this experiment studied the effect of adding GABA and CaCl2 separately and adding their compound on growth,chlorophyll fluorescence and reactive oxygen,etc.indexes of tomato seedlings under salt and alkali stress.The results showed that the growth rates of plant height,stem diameter,root length and number of roots of tomato,its fresh weight and dry weight were all obviously increased under salt and alkali stress,no matter the exogenous GABA and CaCl_(2) were added solely or in combination.The leaf color index was significantly increased and chlorophyll fluorescence parameter was also obviously improved.At the same time,the exogenous GABA and CaCl_(2) separate treatment and compound treatment reduced the reactive oxygen accumulation of tomato leaves.Compared with the separate treatment,SA+CA6+GABA5 treatment had a better alleviating effect on the injury by salt and alkali stress,indicating that the addition of exogenous CaCl2 could promote the ability of GABA in enhancing plants salt and alkali tolerance.