工业污染物的不当排放导致了水体污染，其中镉污染尤为突出，对水生植物造成了严重危害。研究报道抗盐基因Na+/H+ 逆向转运蛋白（NHX1）的表达在镉胁迫下先降低后升高，出现了显著变化。浮萍在水环境检测、生物产能和水体净化中被广泛应用，我们将大豆的NHX1基因在浮萍中过表达后，初步发现NHX1转基因浮萍具有镉胁迫抗性，然而NHX1抗镉胁迫的机制尚不明确。NHX1在镉离子转运中的作用，以及在pH、有机酸、信号通路等方面对镉胁迫抗性的影响需要解析。本研究拟以NHX1转基因浮萍为材料，研究镉胁迫下NHX1转基因浮萍镉吸收的部位和浓度；pH、有机酸的变化及其对镉吸收的影响；乙烯和一氧化氮释放量的变化及相关基因表达量的变化，以期揭示NHX1提高浮萍镉耐受性的机制，并将利于镉污染水境的生态学修复。

The industrial discharge leads to the pollution of water system, with cadmium being the most serious one, and causes a severe impact on the aquatic plants. It has been reported that the expression of Na+/H+ Antiporter 1 (NHX1), a salt tolerant gene, decreases first with the cadium stress and then increases. Duckweed（Lemnaceae）, a type of aquatic plants, is wildly explored in water environmental detection, biofuel research and water purification. Glycine max Na+/H+ Antiporter (GmNHX1) was overexpressed in Lemna minor in our study, and the transgenic duckweed show ed cadmium resistance. We need to further study the function of NHX1 on cadmium transportation, the influence of pH value change, organic acids, and the plant signal regulation on the resistance of cadmium stress. The transgenic Duckweed will be researched as a main material for the following aspects: the location of absorb of cadmium in duckweed with cadmium stress and the concentration; the change of pH value change and the organic acids compounds and the influence of these changes of on the absorb of cadmium; the change of ethylene and NO releasing and the expression of related genes. This study tends to reveal the mechanism of NHX1 improving cadmium resistance, and contribute to the understanding of cadmium resistance study and the ecological restoration of cadmium pollution water system.