碱胁迫下NO和Ca^(2+)对裸燕麦(Avenanuda)幼苗生理特性的影响  

Effects of Exogenous Nitric Oxide and Ca^(2+) on Physiological Characteristics of Avena nuda Seedlings under Alkali Stress

作　　者：刘建新[1] 王金成[1] 王瑞娟[1] 贾海燕[1] 

机构地区：[1]陇东学院生命科学与技术学院/甘肃省高校陇东生物资源保护与利用省级重点实验室,甘肃庆阳745000

出　　处：《中国沙漠》2016年第3期695-701,共7页Journal of Desert Research

基　　金：甘肃省庆阳市科技计划项目(KZ2014-19)

摘　　要：为了探讨NO对碱胁迫下裸燕麦(Avena nuda)生理响应的调节作用,采用营养液培养,研究Ca^(2+)对外源NO供体硝普钠(SNP)所诱导的NaHCO_3胁迫下裸燕麦品种"定莜6号"幼苗生长、活性氧代谢和渗透溶质积累的影响。结果表明:25μmol·L-1SNP或6.5mmol·L-1 CaCl_2能够缓解75mmol·L-1 NaHCO_3胁迫对幼苗生长的抑制作用,叶片超氧化物歧化酶、过氧化氢酶、过氧化物酶、抗坏血酸过氧化物酶和质膜H+-ATP酶活性较单独NaHCO3胁迫处理明显增强,O·-2、H_2O_2、丙二醛含量显著下降,抗坏血酸、可溶性糖、可溶性蛋白质、脯氨酸含量和K+/Na+显著提高;添加SNP的同时增添Ca^(2+)通道抑制剂~La(3+)或Ca^(2+)螯合剂EGTA抑制了SNP的这些作用。Ca^(2+)在NO诱导的碱胁迫下裸燕麦活性氧清除能力和渗透溶质含量提高、维持离子平衡中起重要作用,NO的作用可能依赖于胞浆Ca^(2+)的浓度。To understand the regulative effect of exogenous nitric oxide on physiological response of naked oat（Avena nuda）seedlings under alkali stress,through nutrient solution cultivating in greenhouse,the naked oat cultivar,Dingyou No.6＇,was selected as the plant material and sodium nitroprusside（SNP）was used as nitric oxide donor to investigate the effects of Ca^（2＋） on growth,reactive oxygen metabolism and osmotica accumulation of naked oat seedlings induced by exogenous nitric oxide under NaHCO_3 stress.The results showed that 25μmol·L-1SNP or 6.5 mmol·L-1 CaCl_2 could alleviate the inhibition of 75 mmol·L-1 NaHCO_3 stress to the seedlings growth significantly,and the activities of superoxide dismutase,catalase,peroxidase,ascorbate peroxidase and plasma membrane H＋-ATPase in leaves were enhanced,the contents of O·-2,H_2O_2,malondialdehyde were decreased,and the contents of ascorbic acid,soluble sugar,soluble protein and proline as well as K＋/Na＋ratio were also increased significantly,in respectively.The effect of SNP was decreased after treatment of blocker of plasma membrane Ca^（2＋） channel La^（3＋） or extracellular Ca^（2＋） chelant EGTA.The above results indicated that Ca^（2＋） might play an important role in reactive oxygen metabolism,osmotica accumulation and balance of Na＋and K＋induced by exogenous nitric oxide in naked oat under alkali stress.The effect of nitric oxide here de pends on the content of Ca^（2＋） in cytoplasm.

关 键 词：NO 裸燕麦(Avena nuda) 碱胁迫 活性氧代谢 渗透溶质 

分 类 号：Q945.78[生物学—植物学]