不同pH值下MgO NPs悬浮液中Mg^(2+)质量浓度的动态变化及其对小麦生长的影响

The Changes of Mg^(2+)Mass Concentration in MgO NPs Suspension and Its Effects on the Growth of Wheat(Triticum aestivum L.)under Different pH

MgO NPs在广泛应用的同时会进入到植物的生长环境中,环境的pH值也会影响纳米粒子中金属离子的释放及其与植物间的相互作用。本文选择我国种植面积较大的农作物—小麦(Triticum aestivum L.)为受试对象,使用镁离子选择性微电极研究不同pH值时MgO NPs悬浮液中Mg^(2+)质量浓度的动态变化及其对小麦生长的影响。结果表明,MgO NPs悬浮液中Mg^(2+)质量浓度随时间逐渐增大,48 h后趋于稳定。调节pH值至悬浮液呈酸性促进了Mg^(2+)的释放,对于80 mg/L的MgO NPs悬浮液,pH=6.5时Mg^(2+)质量浓度由未调节pH值时的24.31 mg/L增加到31.47 mg/L。与此同时,小麦对Mg^(2+)的吸收增加,从而在一定程度上减轻了MgO NPs对小麦生长的抑制作用。

When MgO NPs are widely used,they will be leaked into the growth environment of plants.The pH value of the environment will also affect the release of metal ions from nanoparticles and their interaction with plants.In this study,wheat(Triticum aestivum L.),which was largely planged in China,was chosen as the test subject for the investigation of the mass concentration changes of Mg^(2+)ions in MgO NPs suspension at different pH values and its effects on wheat growth via ion-selective microelectrod.The results showed that the mass concentration of Mg^(2+)gradually increased with time and stabilized after 48 h.Adjusting the pH value of the suspenstion to acidic values promoted the release of Mg^(2+).For the 80 mg/L MgO NPs suspension,the mass concentration of Mg^(2+)at pH=6.5 was 24.31 mg/L,increased significantly as compared with that in the unadjusted suspension,31.47 mg/L.At the same time,this adjustment also increased the absorption of Mg^(2+)by wheat,thereby,to a certain extent,reduced the inhibitory effect of MgO NPs on wheat growth.