茶多酚对盐胁迫下小麦幼苗根渗透调节作用的影响

Effect of tea polyphenols on salinity-induced osmotic adjustment in wheat roots

以春小麦新品种"陇春30号"为材料,研究了不同浓度(25和100mg·L^(-1))的茶多酚(Tea polyphenols,TP)对NaCl(150mmol·L^(-1))胁迫下小麦幼苗渗透调节物及脯氨酸代谢相关酶活性的影响.结果表明,150mmol·L^(-1) NaCl处理诱导小麦根中可溶性糖、可溶性蛋白和脯氨酸含量较对照显著升高,而25和100mg·L^(-1) TP单独处理对这些指标无显著影响;与单独150mmol·L^(-1) NaCl处理相比,添加100mg·L^(-1) TP诱导盐处理的根可溶性糖、可溶性蛋白和脯氨酸含量显著降低.盐胁迫、单独TP处理和盐+TP处理都导致小麦根脯氨酸脱氢酶(PDH)活性明显下降;鸟氨酸转氨酶(OAT)活性在盐处理下较对照无明显变化,其他各个处理下活性减弱.谷氨酸激酶(GK)活性在各个处理中无明显变化.盐胁迫和单独TP处理均诱导小麦根Na,K元素含量显著增加,不同浓度TP的加入不显著影响盐诱导的Na,K含量的变化,小麦根在150mmol·L^(-1) NaCl处理后K/Na显著减小,TP的添加不显著影响这种变化.盐胁迫下小麦根Ca元素减少,然而盐胁迫下加入不同浓度(25和100mg·L^(-1))TP后,根中Ca含量显著增加.总之,盐胁迫诱导的小麦根可溶性蛋白、可溶性糖和脯氨酸含量的增加,提高了渗透性调节能力,以缓解盐对植物的伤害;TP的加入逆转了盐诱导的小麦根可溶性糖、可溶性蛋白和脯氨酸等渗透性调节物的积累及Ca元素含量的减少.

Spring wheat cv longchun 30 seedlings are used to investigate effect of tea polyphenols（TP） on osmotic regulators and proline metabolic enzyme activities in salinity-treated roots.The results show that proline,soluble sugar and soluble protein contents significantly elevate in wheat roots exposed to 150 mmol·L^-1 NaCl,but 25 and 100 mg·L^-1 TP alone treatments have no significant effect on these indexes as compared with control.Compared with 150 mmol·L^-1 NaCl alone treatment,soluble sugar,soluble protein and proline contents decrease significantly by adding 100 mg·L^-1 TP in salt treatment.Proline dehydrogenase（PDH） activity decrease in response to salt stress,TP treatments and salt＋TP treatments in wheat roots,ornithine aminotransferase activity（OAT） don＆#39;t change significantly in salt treatment,but OAT activity in other treatments is weakened comparision with control.Glutamate kinase（GK） activity has no obvious change in each treatment.Na and K contents reduce significantly in wheat roots stressed by salt and TP treatment alone,the addition of different TP concentrations do not significantly affect on salinity-induced changes in Na and K contents.After treatment with 150 mmol·L^-1 NaCl,K/Na value decrease significantly in wheat roots,and there has no significant influence on this value by adding TP.Ca content decline in wheat roots treated with salt,however the addition of different TP concentrations lead to the decrease of Ca contents.In summary,salt stress results in significant increases of soluble protein,soluble sugar and proline contents in wheat roots,which is conducive to the improvement of permeability regulation and the relief of salt damage to plants;And also,TP application blocks the accumulation of permeability regulators and the reduction of Ca level in salinity-stressed wheat roots.