Pb、Cd胁迫对紫茎泽兰N、P、K吸收的影响

Effects of lead,cadmium on N,P,K uptake of Ageratina adenophorum

采用模拟Pb、Cd污染土壤培养法研究了紫茎泽兰在重金属Pb、Cd胁迫下植株不同部位对3种营养元素(N、P、K)吸收的影响。结果表明,紫茎泽兰各组织在Pb胁迫下对N、P的吸收总体上均保持一定的促进作用,对K则表现出一定的抑制效应;Cd胁迫下对N、P有良好的吸收,低浓度Cd促进K的吸收,高浓度则表现出抑制作用。Pb-Cd复合污染胁迫下根茎叶均对N的吸收有一定的促进作用,而对K的吸收有较强的抑制效应。这表明,紫茎泽兰在重金属Pb、Cd胁迫下可通过大量吸收N、P等元素来有效缓解重金属的毒害作用,这可能也是紫茎泽兰能适应高Pb、Cd胁迫的一种耐性机制。

The effects of Pb,Cd on nutrient elements （N,P,K）uptake in different parts of Ageratina adenopho-rum were investigated in a soil pot experiment.The results showed that it had a positive effect on the absorption of N,P in different tissues under Pb stress,but negative effect on K uptake.Under the conditions of Cd stress,it was favorable for the absorption of N,P in different tissues,and the absorption of K was promoted at low Cd concentration,but inhibited at high concentration.It also had a positive effect on the absorption of N in different tissues under combined Pb-Cd pollution stress,but negatively affected K uptake.A large quantity of N and P was absorbed to alleviate the toxic effects on A.adenophorum by heavy metals.It is a possible tolerance mechanism of E .adenophorum under Pb and Cd stresses.