FTIR法分析铵盐胁迫对蓝莓组培苗的影响

Effect of Ammonium Stress on Cultured Blueberry Plantlets in vitro Based on FTIR Spectroscopy

以蓝莓组培苗为试材,采用傅里叶变换红外光谱法,研究了正常生长、铵盐胁迫、钙盐缓解3种条件的蓝莓组培苗代谢产物,以期为进一步探讨铵盐胁迫机理提供参考依据。结果表明:3种处理条件下蓝莓组培苗的红外图谱峰形、峰位大体相似,化学物质大体相同,均以蛋白质、脂类和碳水化合物以及少量无机元素为主。铵盐胁迫的植株与正常生长的植株相比,缺少了1 318cm^(-1)附近的吸收峰,此峰可能与细胞膜脂或细胞壁的甲基化程度以及阳离子交换能力相关。与铵盐胁迫植株相比,加入氯化钙缓解的植株增加一条668cm^(-1)的吸收峰,此峰可能与钙离子吸收相关。硫酸铵胁迫导致蓝莓组培苗碳水化合物、脂类、蛋白质含量多呈下降趋势,蛋白质含量的下降趋势要大于多糖。钙离子的补充明显缓解铵盐胁迫,并提高了多糖和蛋白质的积累。

In the current study,in vitro cultured blueberry plantlets were used as materials.The metabolites of in vitro cultured blueberry plantlets under normal growth,ammonium stress and calcium alleviation treatments were analyzed by Fourier transform infrared spectroscopy（FTIR）,which provided further information for the mechanism of ammonium salt stress.The results demonstrated that FTIR peak shape and peak position were similar,and that chemical substances were substantially the same,including protein,lipid and carbohydrates and inorganic elements.Compared with the normal growth plants,lines under ammonium stress lacked the absorption peaks near1 318 cm^-1,which might correlate to the level of cell membrane lipids or the methylation of cell walls and cation exchange capacity.After CaCl2 application,lines showed an absorption peak near 668 cm-（-1） compared with lines under ammonium stress,which might correlate to calcium absorption.Ammonium sulfate stress resulted in a decrease in carbohydrate,lipid and protein contents.The degradation of protein was much more than that of polysaccharides after stress.Supplemental Ca-（2＋）could prevent ammonium damage and the accumulation of substances in blueberry plantlets,especially polysaccharides and proteins.