氮形态和磷肥对红壤玉米根际解磷微生物群落和磷酸酶活性的影响  

Effects of Nitrogen Form and Phosphorus Fertilizer on Phosphorus-solubilizing Bacteria and Phosphatase of Maize Rhizosphere in Acidic Red Soil

作　　者：郭龙 冯童禹 薛壮壮 王超[1] 沈仁芳[1,2] GUO Long;FENG Tongyu;XUE Zhuangzhuang;WANG Chao;SHEN Renfang(State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所),南京210008 [2]中国科学院大学,北京100049

出　　处：《土壤学报》2023年第5期1493-1506,共14页Acta Pedologica Sinica

基　　金：国家自然科学基金项目(42020104004,52022028)资助。

摘　　要：较低的土壤磷素有效性限制了酸性红壤生产潜力提升。作为磷素活化的主要执行者,解磷微生物对施肥和根际作用的综合响应尚不清楚。以玉米为试验材料,设置磷肥水平(施磷和不施磷)与不同氮形态(铵态氮肥和硝态氮肥)的交互试验,使用编码酸性磷酸酶和碱性磷酸酶的微生物phoC和phoD基因作为分子标记物,研究了施肥和根际作用对酸性红壤磷酸酶活性和相关功能微生物群落的影响。结果显示,根际作用显著提高了土壤磷酸酶活性,且作用强度大于氮形态和磷肥水平。氮形态、磷肥水平和根际作用均显著影响phoD细菌操作分类单元(OTU)数目和香农指数,然而仅有氮形态和根际作用影响phoC细菌OTU数目。根际作用对phoC和phoD细菌群落组成结构的影响程度显著高于氮形态和磷肥水平,而且对phoD细菌群落的作用更明显。根际磷酸酶活性提高与土壤有机质增加密切相关。phoC细菌群落组成和结构的变化主要与根际养分变化有关,而phoD细菌群落结构的变化可能是根系分泌物和养分变化共同作用的结果。总体而言,玉米根际作用对酸性红壤磷酸酶活性和相关功能细菌群落的影响大于氮形态和磷肥水平,但是其作用强度一定程度上依赖于上述施肥措施。【Objective】Low phosphorus(P)availability limits the increase in the productive capacity of acidic soils.The bacteria phoC and phoD genes encode acid and alkaline phosphatase(ACP and ALP),respectively,which mineralize organic phosphorus(P)to inorganic P,are affected differently under different fertilization regimes.However,the combined responses of phosphorus-solubilizing microorganisms(PSM)to fertilization strategies and the rhizosphere effect are still unclear.【Method】In this study,it was evaluated the response of maize to the interaction of different nitrogen forms(ammonium nitrogen and nitrate nitrogen)and phosphate fertilizer levels.The phoC and phoD genes,separately coding for acid and alkaline phosphatase productions,were used as molecular markers to investigate the effects of fertilization strategies and rhizosphere effect on soil phosphatase activities and associated functional microbial communities in acidic soil.【Result】The rhizosphere effect significantly increased soil phosphatase activities in the rhizosphere.ALP activities in the rhizosphere under nitrate-nitrogen treatment were lower than in the corresponding ammonium nitrogen treatment.Also,the strength of the rhizosphere effect was greater than that of nitrogen forms and phosphate fertilizer levels.Nitrogen forms,phosphate fertilizer levels and rhizosphere effect all significantly affected the operational taxonomic units(OTU)number and Shannon index of phoD-harboring bacteria,but only nitrogen forms and rhizosphere effect affected the OTU number of phoC-harboring bacteria.Principal coordinate analysis(PCoA)and PERMANOVA analysis showed that the rhizosphere effect exhibited more influence on the phoC-and phoD-harboring bacterial community composition than nitrogen forms and phosphate fertilizer levels,with more effects on the phoD-harboring bacterial community.The stimulation of soil phosphatase activities in the rhizosphere was closely related to the increase in soil organic matter.Additionally,changes in the composition and structure

关 键 词：酸性红壤 施肥措施 根际作用 解磷微生物 磷酸酶活性 

分 类 号：S154.36[农业科学—土壤学]