外源钙对低温胁迫下甜瓜幼苗膜稳定性和渗透调节物质的影响

Effects of Ca on the Membrane Stability and Osmolytes in Melon Seedlings under Low Temperature Stress

采用5mmol/L的CaCl2喷施"二叶一心"期甜瓜幼苗后,置于8℃培养箱中培养,并测定24 h内膜稳定性和渗透调节物质变化.结果表明,低温胁迫下,对照组甜瓜幼苗的丙二醛(MDA)含量和膜透性持续上升,可溶性蛋白和可溶性糖含量均在6 h达到最高,游离脯氨酸和有机酸含量则是在3 h达到最大值.钙处理组的MDA含量、膜透性和渗透调节物质含量变化均与对照组相似,但相同时间段内,可显著降低低温胁迫下甜瓜幼苗MDA积累及细胞膜相对透性,提高蛋白质、可溶性糖和游离脯氨酸含量,而对有机酸含量影响不显著.

5 mmol/L CaCl2 was used to sprayed ＂2-leavies-1-heart＂ stage melon seedlings which cultured under 8 degree low temperature.The changes of membrane stability and Osmolytes contents were studied during 24 hours.The results showed that the contents of soluble protein and soluble sugar at 6 h,the contents of free proline and organic acids at 3 h achieved the maximum values in the controls.Although the change trends of malondialdehyde（MDA） content,membrane permeability and osmolytes content in Ca treatment were similar with controls during 24 hours,but it could evidently reduce MDA accumulation and cell membrane permeability,significantly increase protein,soluble sugar and free proline contents.