砷胁迫对不同物候期香蒲根系分泌物的影响

Effects of arsenic stress on root exudates of Typha angustifolia L.at different phenological phases

为探究典型湿地挺水植物香蒲(Typha angustifolia L.)在砷(As)污染生境中不同物候期的根系分泌物变化特征,测定并分析了As胁迫下的香蒲根系分泌物构成。结果表明:(1)香蒲根系分泌物主要包括烃类、酚类、生物碱类,枯黄期仅有这3类分泌物,幼苗期还有少量唑类,花果期根系分泌物种类最丰富,出现了特有的有机酸类和酯类;(2)香蒲对As具有耐受性,在As胁迫下香蒲通过根系分泌物的改变来适应,如酚类、有机酸类和酯类等,特别是酚类在3个物候期均表现出随As浓度升高而增加的趋势。

In order to explore the variation characteristics of root exudates of the typical emergent aquatic plant Typha angustifolia L.at different phases under As stress,the composition of root exudates was analyzed.Results showed that:(1)the main root exudates of Typha angustifolia L.were hydrocarbons,phenols and alkaloids,which were only contained exudates in withered phase,but there appeared imidazoles in the seedling phase,and moreover,special organic acids and esters appeared in flower and fruit phase,making the most abundant of root exudate.(2)Typha angustifolia L.had tolerance to As by secreting root exudates to adapt the As stress,like phenols,organic acids and esters.In particular,phenols always showed an increasing trend with As concentration increased in all phases.