不同氮、磷浓度对穗花狐尾藻生长及酚类物质含量的影响

为揭示解营养物质对穗花狐尾藻生长及其体内酚类物质的影响,研究了不同氮、磷浓度下穗花狐尾藻体内可溶性糖、可溶性蛋白和总酚含量的变化及与酚类代谢相关酶——苯丙氨酸裂解酶(Pheny lalanine ammonia-lyase,PAL)的活性.结果表明,不同氮、磷条件下,穗花狐尾藻顶端组织中可溶性蛋白含量没有明显变化,低氮、低磷水平下顶端组织中可溶性糖含量分别为50.91、38.25mg.g-1(以干重计),均高于对照组,表明穗花狐尾藻体内可溶性糖对氮、磷胁迫的响应较可溶性蛋白敏感.不同氮浓度(0.875、7.0、56.0mg.L-1)和磷浓度(0.194、1.55、12.4mg.L-1)下,穗花狐尾藻顶端组织中总酚含量分别为44.74、24.42、29.73mg.g-1和37.77、30.60、36.05mg.g-1(以干重计),对应PAL酶活性的变化趋势与酚类物质变化趋势一致,而生物量增长率与酚类物质变化趋势相反,即过高和过低的氮、磷胁迫均会导致穗花狐尾藻生物量增长率的降低及体内酚类物质含量的升高.

Effects of different nitrogen and phosphorus levels on the growth and total phenolic contents of Myriophyllum spicatum

To explore the effect of nutrition on the growth of Myriophyllum spicatum L.and its phenolic content,the levels of soluble sugar,soluble protein and the total phenolic contents and the activity of phenylalanine ammonia-lyase(PAL),an enzyme related with the metabolism of the phenolics,in M.spicatum under different nitrogen(N) and phosphorus(P) levels were investigated.It was discovered that soluble protein in M.spicatum apical meristems showed no difference under different N and P levels,while the concentrations of soluble sugar under low concentration of N and P were 50.91 and 38.25 mg · g-1(dry weight) respectively,both higher than those in the control,which showed that soluble sugar were more sensitive to N and P stress compared with soluble protein in M.spicatum.With the increasing order of the concentration of N(0.875、7.0、56.0 mg · L-1) and P(0.194、1.55、12.4 mg · L-1),the total phenolic contents in test plant were 44.74、24.42、29.73 mg · g-1and 37.77、30.60、36.05 mg · g-1(dry weight),for N and P respectively.The change of the PAL activity was similar to that of the total phenolic contents,while the change of the growth rate of biomass was opposite to that of the total phenolic contents.Both low and high concentration of N and P caused the reduction of biomass growth rate and the increase of total phenolic contents of M.spicatum.