二氧化硫暴露诱发谷子幼苗硫同化作用增强  

The Enhancement of Sulfur Assimilation in Response to Sulfur Dioxide Stress in Foxtail Millet Seedlings

作　　者：杨蕾 韩彦莎[1] 仪慧兰[1] YANG Lei;HAN Yansha;YI Huilan(School of Life Science,Shanxi University,Taiyuan 030006,China)

机构地区：[1]山西大学生命科学学院,山西太原030006

出　　处：《山西大学学报（自然科学版）》2023年第1期229-235,共7页Journal of Shanxi University(Natural Science Edition)

基　　金：国家自然科学基金(31972132);山西省重点研发计划项目(201903D421062)。

摘　　要：二氧化硫(SO_(2))是一种常见的大气污染物,对我国北方地区种植的谷子有一定影响。文章以谷子(Setaria italica L.)“长农44”号的幼苗为材料,采用静态熏气法研究SO_(2)对谷子硫同化作用的影响。结果表明,10 mg·m^(-3)SO_(2)暴露72 h植株地上部分生物量无明显改变;30 mg·m^(-3)SO_(2)暴露72 h时植株地上部分生物量低于对照,硫同化途径中的亚硫酸盐还原酶(SiR)和O-乙酰丝氨酸裂解酶(OASTL)基因表达水平和酶活性均显著提高,硫同化产物半胱氨酸显著增加,但硫酸根(SO42-)还原基因SiAPS转录下调;30 mg·m^(-3)SO_(2)暴露组谷子叶片谷胱甘肽含量提高,谷胱甘肽还原酶(GR)和谷胱甘肽硫转移酶(GST)活性显著增强,还原型/氧化型谷胱甘肽比值明显提高。结果表明,一定浓度的SO_(2)可使谷子幼苗硫同化作用增强,促进含硫抗氧化物质的合成,提升组织的抗氧化能力;与此同时,硫同化途径中SO42-还原为亚硫酸根(SO32-)的过程被抑制,从而调节植株对SO_(2)胁迫的适应。Sulfur dioxide (SO_(2)) is a common air pollutant,which could affect foxtail millet plants grown in North of China.In this study,we investigated the effect of SO_(2)exposure on foxtail millet (Setaria italica L. Changnong 44) seedlings.Our results revealed that exposure to 10 mg·m^(-3)SO_(2)for 72 h did not affect the plant biomass,while the plant biomass were remarkably decreased after 72 h of 30 mg·m^(-3)SO_(2)exposure.Furthermore,72 h of 30 mg·m^(-3)SO_(2)fumigation upregulated the sulfite reductase (SiR) activity and SiSiR gene expression,promoted the O-acetylserinelyase (OASTL) activity and Si OASTL gene expression,and resulted in a significantly higher systeine content.However,the Si APS gene expression was downregulated,suggesting the inhibition of the process of in SO42--SO32-reduction SO_(2)-fumigated plants.Moreover,72 h of SO_(2)fumigation increased the glutathione content,enhanced the activities of glutathione reductase (GR) and glutathione S-transferase (GST),and maintained the high ratio of reduced to oxidized glutathione.Taken together,these results suggested that SO_(2)could enhance sulfur assimilation and increase the levels of GSH to improve the antioxidant capacity of plants.The inhibition of SO42--SO32-reduction could help keeping the relative lower level of SO32-in leave cells to cope with the stress.

关 键 词：谷子 SO_(2) 硫同化 谷胱甘肽 

分 类 号：S515[农业科学—作物学] S423