%0 Journal Article
%T Effects of lanthanum(III) on nitrogen metabolism of soybean seedlings under elevated UV-B radiation<br>Effects of lanthanum（Ⅲ） on nitrogen metabolism of soybean seedlings under elevated UV-B radiation
%A CAO Rui
%A HUANG Xiao-hu
%A ZHOU Qing
%A CHENG Xiao-ying
%A <br>CAO Rui
%A HUANG Xiao-hu
%A ZHOU Qing
%A CHENG Xiao-ying
%J 环境科学学报(英文版)
%D 2007
%I 
%X The hydroponic culture experiments of soybean bean seedlings were conducted to investigate the effect of lanthanum (La) on nitrogen metabolism under two different levels of elevated UV-B radiation (UV-B, 280-320 nm). The whole process of nitrogen metabolism involves uptake and transport of nitrate, nitrate assimilation, ammonium assimilation, amino acid biosynthesis, and protein synthesis. Compared with the control, UV-B radiation with the intensity of 0.15 W/m2 and 0.45 W/m2 significantly affected the whole nitrogen metabolism in soybean seedlings (p < 0.05). It restricted uptake and transport of NO3-, inhibited activity of some key nitrogen-metabolism-related enzymes such as nitrate reductase (NR) related to the nitrate reduction, as well as glutamine systhetase (GS) and glutamine synthase (GOGAT) related to the ammonia assimilation while it increased the content of free amino acids and decreased that of soluble protein as well. The damage effect of high level of UV-B radiation on nitrogen metabolism was greater than that of low one. And UV-B radiation promoted the activity of the anti-adversity enzyme glutamate dehydrogenase (GDH), which reduced the toxicity of excess ammonia in plant. After pretreatment with the optimum concentration of La (20 mg/L), La could increase the activity of NR, GS, GOGAT, and GDH, and ammonia assimilation, but decrease nitrate and ammonia accumulation. In conclusion, La could relieve the damage effect of UV-B radiation on plant by regulating nitrogen metabolism process, and its alleviating effect under low level was better than that under the high one.
%K lanthanum(III)
%K UV-B radiation
%K soybean seedlings
%K nitrogen metabolism
%K alleviating effect
%K lanthanum
%K Effects
%K radiation
%K soybean seedlings
%K better
%K decrease
%K accumulation
%K increased
%K pretreatment
%K the optimum
%K concentration
%K toxicity
%K plant
%K enzyme
%K glutamate dehydrogenase
%K damage effect
%K high
%K level
%K ammonia
%K content<br>lanthanum(Ⅲ)
%K UV-B
%K radiation
%K soybean
%K seedlings
%K nitrogen
%K metabolism
%K alleviating
%K effect
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=3FF3ABA7486768130C3FF830376F43B398E0C97F0FF2DD53&cid=A7CA601309F5FED03C078BCE383971DC&jid=6CB1530875F53489BF1E81BD87B7F5E6&aid=CCA380B04FEA45334A34DAD3166FE341&yid=A732AF04DDA03BB3&vid=2A8D03AD8076A2E3&iid=708DD6B15D2464E8&sid=700C99D38A660C7C&eid=29BFCA84676506CC&journal_id=1001-0742&journal_name=Journalofenvironmentalsciences(China)&referenced_num=0&reference_num=26