摘要
通过实验室静态模拟,研究了在富营养条件下(4.0 mg.L-1TN,0.2 mg.L-1TP)不同比例铵态氮和硝态氮(6∶0、5∶1、3∶3、1∶5和0∶6)对苦草〔Vallisneria natans(Lour.)Hara〕的生长与生理指标的影响。结果表明,随着铵态氮和硝态氮比例的下降,苦草相对生长率和蛋白质含量先升高后下降,超氧化物歧化酶(SOD)和谷氨酰胺合成酶(GS)活性逐渐下降,硝酸还原酶(NR)活性逐渐升高。在4.0 mg.L-1TN和0.2 mg.L-1TP条件下,若不考虑磷的作用,高浓度铵态氮对苦草的生理功能有影响,对其生长有明显的抑制作用;而当铵态氮浓度小于0.67 mg.L-1时却可以促进苦草的生长。
The effects of different ratios of NH4 ^＋ -N to NO3^- -N （6： 0, 5 ： 1, 3 ： 3, 1 ： 5 and 0： 6 ） on growth and physiological indexes of VaUisrteria natans （Lour.） Hara and the mechanism were investigated under eutrophic nutrient condition （4.0 mg · L^-1 TN and 0.2 mg · L^-1 TP） by the static laboratory experiment. The results showed that relative growth rate and protein content first increased significantly then decreased, the activities of superoxide dismutase （SOD） and glutamine synthetase （GS） decreased gradually, the activity of nitrate reductase （NR） increased gradually with decrease of ratio of NH4^＋ -N to NO3^- -N in culture medium. The results indicated that when concentrations of TN and rip were set, the increase of NH4^＋ -N concentration in water could exert a stress influence on normal growth of 11. natans. When the concentration of NH4^＋ -N was lower than 0.67 mg · L^-1, the growth of V. natans was promoted.
出处
《植物资源与环境学报》
CAS
CSCD
2006年第4期48-51,共4页
Journal of Plant Resources and Environment
基金
国家重点基础研究发展规划项目(2002CB412307)
江苏省自然科学基金资助项目(BK2005082)
关键词
苦草
富营养化
铵态氮
硝态氮
生理作用
VaUisneria natans （Lour.） Hara
eutrophic
NH4^＋ -N
NO3^- -N
physiological effect
