中国农业科学 ›› 2022, Vol. 55 ›› Issue (10): 2000-2012.doi: 10.3864/j.issn.0578-1752.2022.10.010

• 土壤肥料·节水灌溉·农业生态环境 • 上一篇    下一篇

丛枝菌根真菌对玉米生育期土壤N2O排放的影响

张学林(),何堂庆,张晨曦,田明慧,李晓立,吴梅,周亚男,郝晓峰   

  1. 河南农业大学农学院/省部共建小麦玉米作物学国家重点实验室/2011河南粮食作物协同创新中心,郑州 450002
  • 收稿日期:2021-03-19 接受日期:2021-06-10 出版日期:2022-05-16 发布日期:2022-06-02
  • 作者简介:张学林,Tel:13643867669;E-mail: xuelinzhang1998@163.com; zxl1998@henau.edu.cn
  • 基金资助:
    河南省自然科学基金(182300410013);国家重点研发计划课题(2018YFD0200605)

Effects of Arbuscular Mycorrhizal Fungi on Soil N2O Emissions During Maize Growth Periods

ZHANG XueLin(),HE TangQing,ZHANG ChenXi,TIAN MingHui,LI XiaoLi,WU Mei,ZHOU YaNan,HAO XiaoFeng   

  1. Agronomy College, Henan Agricultural University/State Key Laboratory of Wheat and Maize Crop Science /Collaborative Innovation Center of Henan Grain Crops for 2011, Zhengzhou 450002
  • Received:2021-03-19 Accepted:2021-06-10 Online:2022-05-16 Published:2022-06-02

摘要:

【目的】明确丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)影响玉米生育期土壤氧化亚氮(N2O)排放的机制,为增加玉米产量、提高氮素利用效率、减少温室气体排放提供理论依据。【方法】采用分室(生长室和菌丝室)箱体装置,盆栽设置氮肥用量(N1:180 kg N·hm-2;N2:360 kg N·hm-2)和丛枝菌根真菌(M0:作物根和AMF均不能从生长室进入菌丝室;M1:只有丛枝菌根真菌能从生长室进入菌丝室;M2:作物根和丛枝菌根真菌均能从生长室进入菌丝室)双因素试验,测定玉米生长期间植株生物量、植株氮素积累量、N2O排放量;采用Illumina平台Hiseq 2500 PE250高通量测序技术分析土壤细菌群落结构和多样性对丛枝菌根真菌的响应。【结果】氮肥用量和丛枝菌根真菌均显著影响玉米产量、植株生物量、植株氮素积累量和N2O排放量。不同氮肥用量条件下接种丛枝菌根真菌均显著增加玉米籽粒产量、植株生物量和氮素积累量。与M0相比,N1条件下M1和M2处理产量均值分别增加38%和82%,地上部氮素积累量增加30%和52%,无机氮含量减少26%和65%;N2条件下M1和M2处理籽粒产量分别增加16%和48%;地上部氮素积累量增加9%和33%,无机氮含量减少34%和55%。与M0相比, N1条件下M1和M2处理N2O累积排放量分别降低17%和40%,N2O排放强度分别降低41%和67%;而N2条件下N2O累积排放量降低26%和45%,排放强度分别降低28%和57%。NMDS 分析表明,施肥和丛枝菌根真菌均对细菌群落结构有较大影响。与N1均值相比,N2处理门水平变形菌门(Proteobacteria)和芽单胞菌门(Gemmatimonadetes)相对丰度分别降低6%和15%,而放线菌门(Actinobacteria)增加32%;属水平链霉菌(Streptomyces)增加27%,芽单胞菌属(Gemmatimonas)降低8%。与M0相比,N1条件下M1和M2处理的Streptomyces分别增加64%和205%,Gemmatimonas细菌丰度分别增加31%和53%;N2条件下M1和M2处理的Streptomyces分别增加10%和93%,M1处理的Gemmatimonas细菌丰度降低2%,M2处理Gemmatimonas细菌丰度增加56%。土壤中StreptomycesGemmatimonas与N2O排放量呈显著负相关,而与玉米产量呈显著正相关。【结论】不同氮肥水平玉米接种丛枝菌根真菌均能显著降低土壤N2O排放量,这种影响主要通过提高玉米氮素的吸收利用和改善土壤细菌群落组成实现的,其中主要增加了土壤链霉菌属和芽单胞菌属的相对丰度。

关键词: 氮肥, 丛枝菌根真菌, 玉米, 土壤氧化亚氮排放通量, 土壤细菌

Abstract:

【Objective】 The aim of this study was to understand the mechanism of arbuscular mycorrhizal fungi (AMF) on soil nitrous oxide (N2O) emissions, so as to provide the theoretical basis for increasing maize yield, improving nitrogen (N) use efficiency and reducing greenhouse gas emissions. 【Method】 A 2-factorial greenhouse experiment was established during maize growth periods in 2016 and 2017. The factors were as follows: (1) N fertilizer rates (180 kg N·hm-2 (N1) and 360 kg N·hm-2 (N2)), and (2) three mycorrhizae treatments, including a control (M0, neither roots nor AMF could enter the hyphal chamber from the growth chamber), an AMF treatment (M1, only AMF can enter the hyphal chamber from the growth chamber), and a root treatment (M2, both roots and AMF can enter the hyphal chamber from the growth chamber). Maize grain yield, plant biomass and their N accumulation, and soil N2O flux were measured. Soil bacterial community structure and diversity at maize maturity stage was determined by using the high throughput sequencing technique on Hiseq 2500 PE250. 【Result】 Both N fertilizer rates and mycorrhizae treatments significantly affected maize yield, plant N accumulation and soil N2O flux. Compared with M0, maize yield under M1 and M2 under the conditions of N1 input increased by 38% and 82%, by 30% and 52% for aboveground N accumulation, respectively, and reduced by 26% and 65% for soil inorganic N, respectively. However, under the conditions of N2 input, the maize yield under M1 and M2 increased by 16% and 48%, by 9% and 33% for aboveground N accumulation, and reduced by 34% and 55% for soil inorganic N, respectively. Compared with the M0, the total N2O emission of M1 and M2 treatments reduced by 17% and 40% under the conditions of N1 input, and by 41% and 67% for the N2O emission intensity, respectively; while under the conditions of N2 input, the total N2O emission reduced by 26% and 45%, and by 28% and 57% for the N2O emission intensity, respectively. Nonmetric multidimensional scaling analysis showed that both N fertilizer rates and mycorrhizae treatments had significant effects on bacterial communities’ composition. Compared with N1, the relative abundance of Proteobacteria and Gemmatimonadetes under N2 treatment on phyla level reduced by 6% and 15%, increased by 32% for Actinobacteria, while on genera level, the Streptomyces increased by 27%, and reduced by 8% for Gemmatimonas. Compared with M0 under the conditions of N1 input, the relative abundance of Streptomyces under M1 and M2 increased by 64% and 205%, by 31% and 53% for Gemmatimonas; however, under the conditions of N2 input, the relative abundance of Streptomyces under M1 and M2 increased by 10% and 93%, respectively, the Gemmatimonas for M1 reduced by 2%, and increased by 56% for M2. Moreover, the relative abundance of soil Streptomyces and Gemmatimonas was negatively related with soil N2O emission, but positively related with maize yield. 【Conclusion】 Arbuscular mycorrhizal fungi could reduce soil N2O emission under both higher and lower N fertilizer application rate by increasing the maize N uptake, and regulating the bacterial composition, especially increasing the relative abundance of Streptomyces and Gemmatimonas.

Key words: nitrogen fertilizer, arbuscular mycorrhizal fungi, maize, soil N2O flux, soil bacteria