摘要
用液体培养,通过测定培养液中的光密度、细菌数量和氨氮,测定了不同浓度Hg2+对蚕豆和银合欢两种根瘤菌的生长的影响,结果表明:两种根瘤菌对不同浓度的Hg2+表现出不同的耐受性,蚕豆根瘤菌可以耐受10ppm浓度的Hg2+,而银合欢根瘤菌只能耐受4ppm以下的Hg2+,但蚕豆根瘤菌的延滞期比银合欢根瘤菌相对要长.两种根瘤菌总的生长趋势是:Hg2+浓度越高,延滞期越长.蚕豆根瘤菌在10ppm以下的Hg2+浓度范围内,表现出较高的固氮活性,而银合欢根瘤菌在Hg2+浓度大于4ppm以后,固氮活性呈现较低的水平.
The optics density, the bacterium quantity and the ammonia nitrogen in the liquid culture medium of Broad bean nodule bacteria and Leucaena leucocephala nodule bacteria with different Hg^2＋ concentration were determined, which showed the influence on the growth of nodule bacteria from Broad bean and Leueaena leucocephala respectively. The results indicated： two kinds of nodules displayed the different tolerance to different Hg^2＋ concentration. The broad bean nodule bacteria may tolerate Hg^2＋ concentration above 10mg/kg but Leucaena leucocephala nodule bacteria may only tolerate 4mg/kg Hg^2＋. However, the lag time of broad bean nodule was relatively longer than that of the Leucaena leucocephala nodule bacteria. The whole growth tendency was： the lag time becomes longer with the higher Hg^2＋ concentration. The broad bean nodule bacteria in 10mg/kg Hg^2＋ displayed the high nitrogen fixation activeness, but the nitrogen fixation activeness of Leueaena leucocephala nodule bacteria presented a lower level above 4rng/kgHg^2＋ .
出处
《广西师范学院学报（自然科学版）》
2007年第3期47-50,共4页
Journal of Guangxi Teachers Education University(Natural Science Edition)
基金
广西自然科学基金项目(桂自0640071)
广西区教育厅自筹基金项目
广西师范学院基础科研基金项目
关键词
汞
蚕豆根瘤菌
银合欢根瘤菌
Nodule bacteria
Mercury
Broad bean
Leucaena leucocephala
