Shen Ju-pei, Zhang Li-mei, Zhu Yong-guan, Zhang Jia-bao, He Ji-zheng
State Key Laboratory of Urban and Regional Ecology, Research Centre for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Environ Microbiol. 2008 Jun;10(6):1601-11. doi: 10.1111/j.1462-2920.2008.01578.x. Epub 2008 Mar 10.
The abundance and composition of soil ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) communities under different long-term (17 years) fertilization practices were investigated using real-time polymerase chain reaction and denaturing gradient gel electrophoresis (DGGE). A sandy loam with pH (H(2)O) ranging from 8.3 to 8.7 was sampled in years 2006 and 2007, including seven fertilization treatments of control without fertilizers (CK), those with combinations of fertilizer nitrogen (N), phosphorus (P) and potassium (K): NP, NK, PK and NPK, half chemical fertilizers NPK plus half organic manure (1/2OMN) and organic manure (OM). The highest bacterial amoA gene copy numbers were found in those treatments receiving N fertilizer. The archaeal amoA gene copy numbers ranging from 1.54 x 10(7) to 4.25 x 10(7) per gram of dry soil were significantly higher than those of bacterial amoA genes, ranging from 1.24 x 10(5) to 2.79 x 10(6) per gram of dry soil, which indicated a potential role of AOA in nitrification. Ammonia-oxidizing bacteria abundance had significant correlations with soil pH and potential nitrification rates. Denaturing gradient gel electrophoresis patterns revealed that the fertilization resulted in an obvious change of the AOB community, while no significant change of the AOA community was observed among different treatments. Phylogenetic analysis showed a dominance of Nitrosospira-like sequences, while three bands were affiliated with the Nitrosomonas genus. All AOA sequences fell within cluster S (soil origin) and cluster M (marine and sediment origin). These results suggest that long-term fertilization had a significant impact on AOB abundance and composition, while minimal on AOA in the alkaline soil.
采用实时聚合酶链反应和变性梯度凝胶电泳（DGGE）技术，研究了不同长期（17年）施肥方式下土壤氨氧化细菌（AOB）和氨氧化古菌（AOA）群落的丰度和组成。于2006年和2007年采集了pH（H₂O）为8.3至8.7的砂壤土样本，包括七种施肥处理：不施肥对照（CK）、氮肥（N）、磷肥（P）和钾肥（K）组合施肥处理（NP、NK、PK和NPK）、半量化学肥料NPK加半量有机肥（1/2OMN）以及有机肥（OM）。发现施氮肥处理中的细菌amoA基因拷贝数最高。每克干土中，古菌amoA基因拷贝数在1.54×10⁷至4.25×10⁷之间，显著高于细菌amoA基因拷贝数，后者每克干土为1.24×10⁵至2.79×10⁶，这表明AOA在硝化作用中具有潜在作用。氨氧化细菌丰度与土壤pH和潜在硝化速率显著相关。变性梯度凝胶电泳图谱显示，施肥导致AOB群落发生明显变化，而不同处理间未观察到AOA群落有显著变化。系统发育分析表明，类硝化螺菌序列占主导地位，同时有三条带与亚硝化单胞菌属相关。所有AOA序列均属于S簇（土壤来源）和M簇（海洋和沉积物来源）。这些结果表明，长期施肥对碱性土壤中的AOB丰度和组成有显著影响，而对AOA的影响最小。
