摘要
以水培大豆为试材,研究了模拟增强紫外辐射UV-B(280～320nm)对大豆幼苗叶片GS、GOGAT、GDH酶活性以及谷氨酸、谷氨酰胺和总游离氨基酸含量的影响,并研究了La(Ⅲ)对UV-B辐射伤害大豆幼苗的缓解效应。结果显示,高(0.45J·m-·2s-1)低(0.15J·m-2·s-1)两个紫外强度剂量下,叶片GS、GOGAT酶活性较对照组显著下降25.9%和11.3%,GOGAT降幅达34.7%和12.6%;经La(Ⅲ)预处理后各组下降幅度都有所减缓,GS降幅为23.1%和7.9%,GOGAT为31%和7.8%,表明La(Ⅲ)对UV-B辐射伤害下,GS、GOGAT酶活性的下降有一定的缓解作用。GDH酶活表现为低强度促进(+30.4%)高强度抑制(-12.8%),且La(Ⅲ)预处理组酶活相应升高,分别为+47%和-9%,三指标连续11d的动态测定结果显示,La(Ⅲ)预处理组酶活性比相应单一UV-B处理组酶活性始终要高,表明适宜浓度的La(Ⅲ)能够提高植物GS、GOGAT和GDH的活性,增强植物氨同化能力,减轻UV-B胁迫对植物造成的伤害。
Effect of La（Ⅲ） on the activities of GOGAT,GS and GDH in leaf were studied as well as content of free amino acid and Glu and Gln in soybean seedlings under the increase of uhravioletB （280-320 nm）radiation. The results showed that under high（0.45 J·m^-2·s^-1） and low（0.15J·m^-2·s^-1） UV-B radiation, the activities of GS and GOGAT in leaf were decreased compared with those of control, with the activities of GS decreasing up to 25.9 % and 11.3%, and GOGAT up to 34.7% and 12.6%, respectively. But pretreated by La（Ⅲ）, the decreased extent of GOGAT and GS were a little lessened, with the decreasing activities of GS 23.1%, 7.9% and GOGAT 31%, 7.8%, suggesting that La（Ⅲ） had some effects on alleviating the harm by UV-B radiation. The change of activity of GDH differed from GS and GOGAT. The activity of GDH increased as much as 130.4% under low intensity of UV-B radiation but decreased as much as 12.8% under high intensity of UV-B radiation, and when pretreated by La（Ⅲ）, the activity of GDH increased to 147.0% and 91% respectively under the two treatments. Through 11 days＂ continual mensuration, the activities of GOGAT,GS and GDH pretreated by La（Ⅲ） were higher than those treated only by UV-B radiation, indicating that La（Ⅲ） had effects on increasing the activities of GOGAT, GS and GDH, and alleviating the harm by UV-B radiation.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2007年第1期146-149,共4页
Journal of Agro-Environment Science
基金
国家发改委稀土专项基金(IFZ20051210)
关键词
镧
紫外辐射
谷氨酰胺合成酶
谷氨酸合成酶
谷氨酸脱氢酶
lanthanum
ultraviolet-B radiation
glutamine synthase
glutamate synthase
glutamate dehydrogenase
