拟南芥莲座叶芥子油苷对聚乙二醇模拟干旱的响应

Effects of Drought Stress Simulated by PEG on Glucosinolates Content in Arabidopsis Thaliana

[目的]研究拟南芥莲座叶芥子油苷对聚乙二醇模拟干旱的响应。[方法]以PEG-6000模拟干旱胁迫,设置对照组和干旱处理组分别培养拟南芥Columbia生态型种子,并在处理后的第0、4、5、6、7d分别取2组拟南芥莲座叶进行生理指标和芥子油苷含量的测定。[结果]干旱胁迫处理后营养生长时期的拟南芥幼苗莲座叶叶片的相对含水量下降,相对电导率(表征膜透性)及丙二醛浓度增加,受损害程度随处理时间的增加而增强。拟南芥莲座叶芥子油苷总量、脂肪族芥子油苷含量及吲哚族芥子油苷含量均在处理后第5天达到最大值,在处理后第6天迅速下降并低于对照组。各种芥子油苷含量变化存在差异,其中含量最高的4MSOB与芥子油苷总量变化趋势一致且差异显著,脂肪族芥子油苷响应干旱胁迫较吲哚族芥子油苷强烈。4MSOB等部分芥子油苷占芥子油苷总量的比例在干旱处理后发生变化并且与其本身含量变化相关。[结论]干旱胁迫确实对拟南芥莲座叶中芥子油苷总量、脂肪族芥子油苷及吲哚族芥子油苷的含量产生影响,使芥子油苷参与到植物对外界干旱胁迫的防御反应中,但长期的干旱胁迫不利于叶片中芥子油苷的积累。

[Objective] The paper aimed to study effects of drought stress simulated by PEG on glucosinolates content in Arabidopsis Thaliana. [Method] Drought stress was simulated by PEG-6000,ecological seeds of Arabidopsis thaliana were cultivated by the control group and drought treatment group respectively. Physical signs of Arabidopsis thaliana and contents of glucosinolates were determined after 0,4,5,6,7 d treatment. [Result] The results showed that leaf water content of rosette leaves was obviously decreased,leaf relative conductivity （characterized by membrane permeability） and the concentration of MDA increased,the extent of damage increased with the increased time. Content of total glucosinolate,aliphatic glucosinolate and indole glucosinolate increased got their maximum after 5 days treatment,and rapidly decreased after 6 and 7 days of treatment,even much lower than the control group. Each kind of glucosinolate changed with difference from each other. 4MSOB which made the most proportion of the total glucosinolate changed consistently with the total glucosinolate and difference significant. As a whole,aliphatic glucosinolates were more sensitive to drought than indole glucosinolate. The proportion of some kind glucosinolate,like 4MSOB varied had correlation with the content change. [Conclusion] Drought stress had an effects on the contents of total glucosinolate,aliphatic glucosinolate and indole glucosinolate,which made the glucosinolate participated in defense response of plant to the outside of drought stress,but long-term drought stress in leaves was not conducive to the accumulation of glucosinolates.