氨氧化微生物通过影响氮素在土壤中的转化而间接影响作物对不同氮素形态的吸收。因此，本实验采集了海南省种植香蕉的滨海土壤，通过施用硫酸铵和硝酸钙，研究了氨氧化细菌(AOB)和氨氧化古菌(AOA)的数量与群落的变化，并测定了香蕉的生长与氮营养状况。通过构建氨氧化细菌和古菌的功能基因amoA文库后发现：施用硫酸铵的土壤中AOB的amoA基因拷贝数显著高于施用硝酸钙的土壤和不施肥的土壤，而AOA的拷贝数低于硝酸钙与不施肥处理。但是氨氧化古菌AOA的绝对数量都高于AOB。施用硫酸铵的土壤中AOB的群落多样性和丰富度明显增加，而施用硝酸钙的土壤却没有发生显著变化。施用硫酸铵和硝酸钙的土壤中AOA群落结构相似，但丰富度和多样性均高于不施肥处理。从施肥效果看，相比硫酸铵，硝酸钙显著提高了香蕉植株的生物量和全氮含量。上述结果表明，在南方酸性土壤中AOA占优势，虽然施用铵态氮肥可以促进AOB的丰度与多样性，但是很可能会抑制AOA的数量。因此，在海南滨海土中施用铵态氮肥后，通过硝化作用以满足香蕉吸收硝态氮的需求达不到理想的效果，应直接补充硝态氮肥来促进香蕉生长。

Ammonia oxidizing microorganisms in the soil affects the conversion of nitrogen and indirectly affect crop nutrient absorption and nitrogen utilization. Therefore, this study investigated the banana plant growth and the community composition and abundance of ammonia oxidisers in soils after application of different nitrogen form fertilizers. The banana plants were cultivated in pots with soil collected from Ledong coast.(NH₄)₂SO₄ and Ca(NO₃)₂ were applied as N fertilizers. Plant growth and nutrient contents were determined. Soil ammonia oxidizing amoA gene clone library was constructed and analyzed. The results indicated that the copy number of the AOB amoA gene under (NH₄)₂SO₄ treatment was significantly higher than the control and Ca(NO₃)₂ treatment, the copy number of AOA amoA was the lower than the control andCa(NO₃)₂ treatment. But the absolute number of ammonia-oxidizing archaea AOA in general were much higher than the number on the AOB. Community diversity and richness of AOB amoA also increased significantly under (NH₄)₂SO₄ treatment. However, the administration of Ca(NO₃)₂ did not change significantly. The community structure of AOA was similar between the (NH₄)₂SO₄ and Ca(NO₃)₂ treatments, but the richness and diversity were higher than the control without fertilization. From fertilization effect, compared with ammonium sulfate, calcium nitrate significantly increased biomass and nitrogen content of banana plants. These results indicated that, in the south acidic soils with AOA predominate, the application of ammonium nitrogen fertilizer can promote AOB abundance and diversity, but is likely to inhibit the number of AOA. Therefore, in the littoral soil after application of ammonium nitrogen fertilizer, through nitrification can’t meet the needs of banana absorbing nitrate, and nitrate fertilizer should be applied directly to promote the growth of bananas.

S145.9

教育部新世纪优秀人才项目(NCET－11－0672)资助