摘要
以两种耐铝性不同蓼科荞麦属植物荞麦和金荞麦为材料,通过土培盆栽试验,比较研究其根际土壤微生态对铝胁迫反应的差异。结果表明,一定质量分数的Al对荞麦和金荞麦根际土壤细菌具有显著刺激效应,对金荞麦的影响更大,但Al质量分数过高,对细菌的刺激效应明显减弱,甚至产生抑制作用,荞麦和金荞麦根际土壤真菌数量均随着Al质量分数的升高而明显增加,荞麦根际土壤真菌增加幅度更为显著,Al胁迫下二者根际放线菌数量的变化亦表现出一定的差异;Al胁迫下,荞麦和金荞麦根际土壤氨化细菌、硝化细菌、反硝化细菌等氮素生理群微生物的变化趋势亦显示出明显差异,整体上荞麦根际土壤细菌生理群对Al胁迫比金荞麦更敏感;Al胁迫对荞麦和金荞麦根际土壤过氧化氢酶活性均表现出较弱的抑制效应,但荞麦根际土壤始终维持较金荞麦更高的过氧化氢酶活性,这与荞麦具有更强的耐铝性有一定的关系,荞麦和金荞麦根际土壤转化酶对Al非常敏感,随着铝的加入,其活性显著下降,荞麦和金荞麦根际土壤脲酶活性的变化趋势基本一致,但整体上荞麦根际土壤脲酶活性均明显低于金荞麦,这是否与其耐铝毒特性的差异有关有待于进一步探讨。
The influence of Al on the microflora and enzyme activities in the rhizosphere soil of buckwheat and gold buckwheat were studied though pot culture. The results showed that the bacteria and actinomyces in the rhizpsphere soil of both buckwheat and gold buckwheat increased dramatically in some range, but decreased at higher Al^3＋concentrations. With the increase of Al^3＋ concentration, the bacteria in the rhizosphere soil of the two plants increased 327.27% and 688.52% respectively, the actinomyces 600.00% and 303.88% respectively. Al showed a more obvious stimulative effect on soil fungi of buckwheat than on that of gold buckwheat. The ammoifier, nitrifler, and denitrifler of buckwheat were more sensitive to the stress of aluminum than those of gold buckwheat. The catalase activity in the rhizosphere soil of both plants decreased slightly under the stress of Al3＋, whereas catalase activity in the rhizosphere soil of buckwheat was, comparatively, higher than that of gold buckwheat all the time, which seemed related to the difference of tolerance to Al^3＋. With the increasing of Al^3＋ concentration, the invertase activity in the rhizosphere soil of both plants decreased sharply. Al^3＋ stress showed similar effect on the urease activity, but urease in the rhizosphere soil of the buckwheat was less active than that of gold buckwheat all along. In conclusion, obviously different responses of microflora and enzyme activities to Al^3＋ stress occurred in the rhizosphere soil, and whether the difference had relation with the difference of tolerance to Al^3＋ stress remains to probe into further.
出处
《生态环境》
CSCD
北大核心
2008年第6期2381-2386,共6页
Ecology and Environmnet
基金
国家自然科学基金项目(30540056)
浙江省自然科学基金项目(305151
304135)
关键词
铝
荞麦
金荞麦
土壤微生物
土壤酶
aluminum
buckwheat
gold buckwheat
microflora
soil enzyme activities
