有机与无机肥配施对拔节期小麦根际反硝化微生物群落结构的影响  

Effect of Combined Application of Organic and Inorganic Fertilizer on Denitrifiers Community Structure in Wheat Rhizosphere at Jointing Stage

作　　者：车钊 罗华影 丁凤磊 张浩苏 姜方莹 张宗祥 董召荣[1] 宋贺[1] CHE Zhao;LUO Huaying;DING Fenglei;ZHANG Haosu;JIANG Fangying;ZHANG Zongxiang;DONG Zhaorong;SONGHe(College of Agronomy,Anhui Agricultural University/Key Laboratory of Wheat Biology and Genetic Improvement on SouthernYellow&Huai River Valley,Ministry of Agriculture and Rural Affairs,Hefei,Anhui 230036,China)

机构地区：[1]安徽农业大学农学院/农业农村部黄淮南部小麦生物学与遗传育种重点实验室,安徽合肥230036

出　　处：《麦类作物学报》2022年第12期1499-1508,共10页Journal of Triticeae Crops

基　　金：安徽省自然科学基金项目(2108085QC112);安徽省高等学校自然科学研究重点项目(KJ2019A0177);安徽省现代农业产业技术体系建设专项。

摘　　要：为探究有机、无机肥配施对拔节期小麦根际反硝化微生物群落结构和功能的影响,依托有机、无机肥配施长期定位试验,设单施化肥(T1)、15%羊粪配施化肥(T2)、30%羊粪配施化肥(T3)和45%羊粪配施化肥(T4)4个施肥处理,以及拔节前期和拔节后期2个追肥时间,利用real-timePCR和高通量测序技术,分析了有机、无机肥配施对拔节期小麦根际nirS和nirK型反硝化微生物丰度及群落结构、反硝化能力(DC)、土壤呼吸(SR)等指标的影响。结果表明,较拔节前期,拔节后期小麦根际土壤中DC和SR显著降低,DOC、NO_(3)^(-)-N含量显著下降,pH和nirS丰度显著提高;相关性分析表明,DC与DOC和NO_(3)^(-)-N分别呈极显著(P<0.01)和显著(P<0.05)正相关,与pH和nirS丰度分别呈极显著(P<0.01)和(P<0.05)显著负相关,与nirK丰度无显著相关性。在拔节后期,较单施化肥处理有机、无机肥配施处理的DC和SR均显著降低;DC和SR及nirK丰度随着有机肥比例提高呈下降趋势,nirS丰度呈上升趋势;nirK型菌群α多样性指数提高,但不同处理间差异不显著;nirS型菌群丰度随着有机肥比例提高呈不断下降趋势。RDA分析表明,pH和NO_(3)^(-)-N是影响nirK型反硝化细菌群落结构的主要因素,NO_(3)^(-)-N和NH_(4)^(+)-N含量是影响nirS型反硝化细菌群落结构的主要因素。相关分析表明,施用有机肥处理的DC与nirK丰度和nirS型菌群落Chao1指数均呈极显著正相关,与nirS丰度均呈极显著负相关。在拔节后期,小麦可通过减少根际DOC含量、提高pH而削弱根际反硝化能力,降低氮素损失;提高有机肥施入比例可改变小麦根际NO_(3)^(-)-N含量,降低nirK型反硝化微生物丰度,改变反硝化微生物群落结构,进而降低根际反硝化能力,缓解拔节后期低氮胁迫对小麦生长造成的不良影响。In order to investigate the effects of organic-inorganic fertilizer ratio on the structure and function of denitrifiers community in wheat rhizosphere at the jointing stage,a long-term positioning experiment with combined application of organic and inorganic fertilizers was conducted.Four treat-ments were set up:single application of chemical fertilizer(T1),15%sheep manure combined with chemical fertilizer(T2),30%sheep manure combined with chemical fertilizer(T3),and 45%sheep manure combined with chemical fertilizer(T4).The soil samples were collected at early and late jointing stage.The abundance and community structure of nirS-type and nirK-type denitrifiers were explored using real-time PCR and high-throughput sequencing technology,and laboratory culture experiment was conducted to investigate denitrification capacity and soil respiration in wheat rhizosphere at jointing stage.The results showed that,compared with early jointing stage,the soil DC,SR,dissolved organic carbon(DOC)and NO_(3)^(-)-N were significantly decreased at late jointing stage in wheat rhizosphere.Soil pH and nirS-type denitrifier abundance were significantly increased at late jointing stage.Correlation analysis showed that DC was significantly positively correlated with DOC(P<0.01)and NO_(3)^(-)-N(P<0.05)contents,but negatively correlated with pH(P<0.01)and nirS-type denitrifier abundance(P<0.05),and no significant correlation with nirK-type denitrifier abundance.Compared with inorganic fertilizer alone,the soil DC and SR of organic-inorganic combined application were significantly reduced at late jointing stage.Under the treatment of applying organic fertilizer,the abundance of soil DC,SR and nirK-type decreased with the increase of the proportion of organic fertilizer,and the abundance of nirS-type increased.Compared with the application of inorganic fertilizer only,combined application of organic-inorganic fertilizer improved theα-diversity index of nirK-type denitrifier community.However,there was no significant difference among differ

关 键 词：有机、无机肥配施 拔节期 根际土 反硝化能力 反硝化微生物群落结构 

分 类 号：S512.1[农业科学—作物学] S330