以新发现的锰耐性植物商陆为实验材料,研究在不同Mn2+浓度下(0.005,02,0.5,1 0,2.0,5 0和10.0 mmol/L)商陆不同组织器官的傅里叶红外光谱(FTIR)图谱变化.研究结果表明:茎组织在3 420和2 926 cm-1处峰高先上升后下降,反映糖类和氨基酸等有机物在低Mn2+条件下往往作为渗透性调节物质出现,其含量升高；但随着Mn2+浓度的升高,其合成和运输受限,有机物含量逐渐下降;根组织在2 926 cm-1处峰先减弱后增强,说明商陆分泌的有机酸不断螯合Mn2+,造成羧酸O-H减少；随着Mn2+浓度的升高,其羧酸螯合力变弱；叶组织在1640 cm-1处的显著吸收峰可能与商陆叶中氨基酸、多肽和蛋白质类物质含量升高有关,或与根部输送的羧酸盐过多有关,且与根部此处峰值的下降趋势相吻合;商陆根、茎、叶在1 060 cm-1处和最高浓度下峰值的变化主要表现在膜脂过氧化,这可能与商陆的锰耐性有关.%A technique based on Fourier transform infrared (FTIR) spectrometiy was used to explore the physiological changes in chemical composition of Phytolacca acinosa in a wide range of Mn2+ concentration (0.005, 0.2, 0.5, 1.0, 2.0, 5.0,10.0 mmol/L). The results show that the absorption bands at 3 420 and 2 926 cm-1 of stem tissues increase firstly and then decrease, indicating the exudation and transporting situation of organic substances which serves as organic osmotic contents to enhance manganese tolerance during low treatments. Meanwhile, the bands at 2 926 cm-1(roots) and 1 640 cm-1(leaves) have different tendencies in accordance with Mn2+ treatments, which shows that the capability to chelate Mn decreases under higher manganese concentration. In addition, the changes of the bands at 1 060 cm-1 differ from each other, suggesting that under the conditions of Mn2+ concentration, the ex-oxidation of membrane lipid increases. It is practical to apply FTIR to compare the chemical differences of the tolerate plants during metal treatments.
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