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作 者 ：韩 超1，申海玉1，叶 嘉1,杨 利2，梁 爽3

期 刊 ：西北植物学报 2012年 4期 页码：745~750

关键词：脱落酸；小麦；镉胁迫；抗性；

Keywords:abscisic acid, wheat, cadmium stress, resistance,

摘 要 ：以小麦（Triticum aestivum L.）为试材，采用水培法研究了100 mg/L镉（Cd²⁺）胁迫条件下施用外源脱落酸（ABA）对小麦幼苗生长及某些生理生化指标的影响。结果表明：（1）100 mg/L Cd²⁺胁迫下，小麦叶片膜脂过氧化产物丙二醛（MDA）含量显著提高，植株生长受到抑制；（2）外源ABA能够明显提高Cd²⁺胁迫小麦幼苗的根系活力，增加其叶片SOD、CAT和POD活性，促进其脯氨酸积累，降低MDA的含量，并以5.0 μmol/L ABA的效果最明显；（3）1.0～5.0 μmol/L外源ABA不同程度地缓解Cd²⁺胁迫对小麦幼苗生长的抑制作用，且5.0 μmol/L时效果最明显，其株高、根长、总干重分别比单一Cd²⁺胁迫处理显著提高6.73%、149%和10.52%，而10.0 μmol/L ABA反而加重了Cd²⁺对小麦幼苗生长的伤害。因此，适宜浓度的外源 ABA能够通过增加体内保护酶活性和脯氨酸含量来缓解Cd²⁺胁迫对小麦幼苗生长的抑制作用，增强小麦幼苗的抗Cd²⁺胁迫能力，并以5.0 μmol/L ABA处理效果最好。

Abstract:Effects of exogenous abscisic acid (ABA) on the growth and some physio-biochemical signs in wheat (Triticum aestivum L.) seedlings under cadmium stress (100 mg/L) were studied with hydroponics.The results showed that:(1)The malondialdehyde (MDA) content in wheat seedlings was significantly increased (P<0.05),and the growth of wheat seedlings was also obviously inhibited by Cd²⁺ stress.(2)Exogenous ABA with the concentration of 5.0 μmol/L playing a noticeable role increased root activity and proline content,enhanced activities of SOD,POD and CAT,and decreased MDA content.(3)Exogenous 1.0~5.0 μmol/L ABA eased the negative effects of Cd²⁺ on the growth of wheat seedlings,and 5.0 μmol/L ABA worked best with shoot height,root length and total biomass of seedlings in 5.0 μmol/L ABA and Cd²⁺ stress had increased 6.73%,149% and 10.52%,respectively,compared with those under single Cd²⁺ stress.However,10.0 μmol/L ABA exacerbated the growth of wheat seedlings.On the whole,preference concentration of exogenous ABA could ease the inhibitory effects of Cd²⁺ stress on the growth of wheat seedlings and boost the tolerance of wheat seedlings to Cd²⁺ stress by increasing SOD,POD and CAT activities and proline content.Furthermore,the most suitable concentration of ABA was defined to be 5.0 μmol/L.

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