CO_2倍增和UV-B辐射增强对大豆根际氨氧化细菌数量及土壤酶活的影响

Effects of Doubled CO_2 and Enhanced UV-B Radiation on Rhizosphere Ammonia-oxidizing Bacteria and Soil Enzymes in Soybean(Glycine max Merr.)

以根瘤超着生大豆突变体0498和完全不结瘤的大豆突变体0701为材料,在人工气候室内模拟大气CO2浓度倍增以及UV-B辐射增强的复合逆境胁迫条件,研究其对大豆根际氨氧化细菌数量和根际土壤酶活的影响。结果表明:与对照相比,CO2浓度倍增能显著提高大豆根际氨氧化细菌的数量,增加土壤中脲酶、转化酶、酸性磷酸酶和碱性磷酸酶的活性,对完全不结瘤的0701影响更加显著;UV-B辐射增强对氨氧化细菌数量无显著影响,对土壤酶活存在一定的抑制作用。超量根瘤的存在,使CO2倍增和UV-B辐射增强对上述指标的影响得到一定的缓解。

The increase of atmospheric CO2 concentration and ultraviolet-B radiation（UV-B）significantly affect crops growth,development and physiological processes.In this study,the soil enzyme activities and amount of soybean rhizosphere ammonia-oxidizing bacteria were analyzed under the condition of doubled CO2 concentration and enhanced UV-B irradiation.Related experiments were imitated in artificial climate room using super-nodulating mutant 0498 and not nodulated soybean mutant 0701 as materials.The results showed that,the amounts of soybean rhizosphere ammonia-oxidizing bacteria activities of soil urease,invertase,acid phosphatase and alkaline phosphatase of doubled CO2were enhanced compared with CK;the influence on 0701 was more significant.UV-B had no effect on amounts of soybean rhizosphere ammonia-oxidizing bacteria and reduced soil enzymes activities.The existence of super nodule could lessen the influence of CO2 concentration and UV-B irradiation on soybean rhizosphere ammonia-oxidizing bacteria and soil enzyme activities.