摘要
为探究外源一氧化氮(NO)供体硝普钠(SNP)对棉花幼苗耐盐性影响的生理机制,以棉花品种‘新陆早48号’为供试材料,采用室外盆栽蛭石培养法,研究外施不同浓度(0、50、100、200和400μmol·L^(-1))SNP对不同程度(0、100和200 mmol·L^(-1))NaCl胁迫下棉花幼苗生物量、光合特性及抗氧化酶活性的影响。结果表明:NaCl胁迫严重抑制了棉花幼苗生长,降低叶片中叶绿素含量、叶绿素荧光参数和光合气体交换参数,削弱抗氧化酶活性,且NaCl浓度越高,棉花幼苗受到的伤害越严重。而经不同浓度SNP处理可显著提高NaCl胁迫下棉花幼苗干物质合成速率,从而促进棉花幼苗生长;增大叶绿素积累量,提高光合效率;显著提高NaCl胁迫下棉花幼苗抗氧化酶活性。其中以200μmol·L^(-1)的SNP效果最佳。综上所述,外源SNP能够通过促进棉花幼苗生长及光合效率,降低NaCl胁迫诱导的氧化损伤,并提高抗氧化酶活性,降低盐胁迫衍生的活性氧而造成的膜脂过氧化程度,从而缓解盐胁迫对棉花幼苗生长的抑制,提高棉花耐盐性。
In order to investigate the physiological mechanism of the effect of exogenous nitric oxide(NO)donor sodium nitroprusside(SNP)on salt tolerance of cotton seedlings,the cotton(Gossypium hirsutum)variety’Xinluzao 48’was used as the test material.Effects of different concentrations of SNP(0,50,100,200,400μmol·L^(-1))on biomass,photosynthetic characteristics and antioxidant enzyme activities of cotton seedlings under different levels of NaCl stress(0,100,200,400 mmol·L^(-1))were explored by the method of outdoor pot culture on vermiculite.The results showed that NaCl stress seriously inhibited the growth of cotton seedlings,reduced the chlorophyll accumulation,chlorophyll fluorescence parameters and photosynthetic gas exchange parameters,decreased the activities of antioxidant enzymes.The higher NaCl concentration was,the more serious the damage was to cotton seedlings.After different concentrations of SNP treatment,the dry matter synthesis rate of cotton seedlings under NaCl stress was significantly increased and the growth of cotton seedlings was promoted.The chlorophyll biosynthesis rate was expedited and the photosynthetic efficiency was improved.The antioxidant enzyme activities of cotton seedlings under NaCl stress was significantly increased.The concentration of SNP with 200μmol·L^(-1)was the best.In conclusion,exogenous SNP could promote the growth and photosynthetic efficiency of cotton seedlings,reduce the oxidative damage induced by NaCl stress,increase the activity of antioxidant enzymes,and reduce the degree of membrane lipid peroxidation caused by reactive oxygen species derived from salt stress,so as to SNP could alleviate the inhibition of salt stress on cotton seedling growth and improve the salt tolerance of cotton.
作者
吴莺
张淑英
陈明媛
王梦柯
WU Ying;ZHANG Shuying;CHEN Mingyuan;WANG Mengke(Agricultural College of Shihezi University,Shihezi,Xinjiang 832003,China)
出处
《植物生理学报》
CAS
CSCD
北大核心
2022年第4期757-766,共10页
Plant Physiology Journal
基金
国家自然科学基金(41461064)。
关键词
外源NO
盐胁迫
棉花幼苗
光合特性
抗氧化酶
exogenous NO
salt stress
cotton seedlings
photosynthetic characteristics
antioxidant enzymes
