1
|
Gao C, Bezemer TM, de Vries FT, van Bodegom PM. Trade-offs in soil microbial functions and soil health in agroecosystems. Trends Ecol Evol 2024:S0169-5347(24)00138-1. [PMID: 38910081 DOI: 10.1016/j.tree.2024.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 04/24/2024] [Accepted: 05/31/2024] [Indexed: 06/25/2024]
Abstract
Soil microbial communities play pivotal roles in maintaining soil health in agroecosystems. However, how the delivery of multiple microbial functions in agroecosystems is maintained remains poorly understood. This may put us at risk of incurring unexpected trade-offs between soil functions. We elucidate how interactions between soil microbes can lead to trade-offs in the functioning of agricultural soils. Interactions within soil microbial communities can result in not only positive but also neutral and negative relationships among soil functions. Altering soil conditions through soil health-improving agricultural management can alleviate these functional trade-offs by promoting the diversity and interrelationships of soil microbes, which can help to achieve more productive and sustainable agroecosystems.
Collapse
Affiliation(s)
- Chenguang Gao
- Environmental Biology, Institute of Environmental Sciences, Leiden University, Einsteinweg 2, 2333 CC Leiden, The Netherlands.
| | - Thiemo Martijn Bezemer
- Institute of Biology, Above-Belowground Interactions Group, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Franciska T de Vries
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1090 GE Amsterdam, The Netherlands
| | - Peter M van Bodegom
- Environmental Biology, Institute of Environmental Sciences, Leiden University, Einsteinweg 2, 2333 CC Leiden, The Netherlands
| |
Collapse
|
2
|
Jia X, Shang H, Chen Y, Lin M, Wei Y, Li Y, Li R, Dong P, Chen Y, Zhang Y, Wang Q. Improved bacterial composition and co-occurrence patterns of rhizosphere increased nutrient uptake and grain yield through cultivars mixtures in maize. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:172102. [PMID: 38556018 DOI: 10.1016/j.scitotenv.2024.172102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 03/26/2024] [Accepted: 03/28/2024] [Indexed: 04/02/2024]
Abstract
Crop diversification contributes to agricultural productivity and resources efficient utilization. However, whether cultivar mixtures in maize affects soil bacterial community, nutrient uptake, plant growth and yield remains unknown. A two-year lysimetric experiment was conducted using two maize cultivars (LY16 and JS501) with different root system architectures planted in monoculture or in mixture under normal fertilization (NF), reduced fertilization (RF) or no addition of fertilizer (CK) and was assessed at the silking stages. Cultivar mixtures and monoculture of LY16 had higher shoot biomass, nutrient uptake and total root length at silking stage, and grain yield than monoculture of JS501 under NF and RF conditions. Under NF and RF conditions, cultivar mixtures and monoculture of LY16 led to an increase in bacterial diversity, significant changes in community structure, and a high abundance of Bacteroidia and biomarkers of Chitinophagaceae and Saprospiraceae (Bacteroidia). Cultivar mixtures showed specific responses from modules of the rhizosphere bacterial community co-occurrence network, and the relative abundance of keystone taxa of cultivar mixtures was higher than that of monoculture of JS501. The keystone taxa had a broad and significant positive correlation with plant nutrient accumulation and grain yield. Cultivar mixtures showed similar assembly processes of Bacteroidia with monoculture of LY16, and the increased abundance of Chitinophagaceae may lead to a healthy rhizosphere bacterial community. Overall, our findings indicate that cultivar mixtures significantly affects the assembly and composition of the rhizosphere bacterial community, and thus benefits plant nutrient acquisition and plant growth. These findings could deepen our understanding of the facilitating effect of rhizosphere functional microbial community (e.g. plant nutrition uptake or immunity)of cultivar mixtures.
Collapse
Affiliation(s)
- Xucun Jia
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China; The State Key Laboratory of Wheat and Maize Crop Science and Center for Crop Genome Engineering, Henan Agricultural University, Zhengzhou 450046, China; Henan Province Agro-ecosystem Field Observation and Research Station, Xiping 463900, China
| | - Haipeng Shang
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China
| | - Yibo Chen
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China
| | - Mengjie Lin
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China
| | - Yuepeng Wei
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China
| | - Yuxia Li
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China; The State Key Laboratory of Wheat and Maize Crop Science and Center for Crop Genome Engineering, Henan Agricultural University, Zhengzhou 450046, China; Henan Province Agro-ecosystem Field Observation and Research Station, Xiping 463900, China
| | - Rongfa Li
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China; The State Key Laboratory of Wheat and Maize Crop Science and Center for Crop Genome Engineering, Henan Agricultural University, Zhengzhou 450046, China; Henan Province Agro-ecosystem Field Observation and Research Station, Xiping 463900, China
| | - Pengfei Dong
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China; The State Key Laboratory of Wheat and Maize Crop Science and Center for Crop Genome Engineering, Henan Agricultural University, Zhengzhou 450046, China; Henan Province Agro-ecosystem Field Observation and Research Station, Xiping 463900, China
| | - Yinglong Chen
- UWA Institute of Agriculture, School of Agriculture and Environment, The University of Western Australia, Perth, WA 6155, Australia
| | - Yongen Zhang
- Agricultural Information Institute of Chinese Academy of Agricultural Science, Beijing 100000, China.
| | - Qun Wang
- College of Agronomy, Henan Agricultural University, Zhengzhou 450046, China; The State Key Laboratory of Wheat and Maize Crop Science and Center for Crop Genome Engineering, Henan Agricultural University, Zhengzhou 450046, China; Henan Province Agro-ecosystem Field Observation and Research Station, Xiping 463900, China.
| |
Collapse
|
3
|
Li R, Jiao H, Sun B, Song M, Yan G, Bai Z, Wang J, Zhuang X, Hu Q. Understanding Salinity-Driven Modulation of Microbial Interactions: Rhizosphere versus Edaphic Microbiome Dynamics. Microorganisms 2024; 12:683. [PMID: 38674627 PMCID: PMC11052110 DOI: 10.3390/microorganisms12040683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 03/16/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
Soil salinization poses a global threat to terrestrial ecosystems. Soil microorganisms, crucial for maintaining ecosystem services, are sensitive to changes in soil structure and properties, particularly salinity. In this study, contrasting dynamics within the rhizosphere and bulk soil were focused on exploring the effects of heightened salinity on soil microbial communities, evaluating the influences shaping their composition in saline environments. This study observed a general decrease in bacterial alpha diversity with increasing salinity, along with shifts in community structure in terms of taxa relative abundance. The size and stability of bacterial co-occurrence networks declined under salt stress, indicating functional and resilience losses. An increased proportion of heterogeneous selection in bacterial community assembly suggested salinity's critical role in shaping bacterial communities. Stochasticity dominated fungal community assembly, suggesting their relatively lower sensitivity to soil salinity. However, bipartite network analysis revealed that fungi played a more significant role than bacteria in intensified microbial interactions in the rhizosphere under salinity stress compared to the bulk soil. Therefore, microbial cross-domain interactions might play a key role in bacterial resilience under salt stress in the rhizosphere.
Collapse
Affiliation(s)
- Rui Li
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (R.L.); (H.J.); (B.S.); (M.S.); (G.Y.); (Z.B.); (X.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
- Binzhou Institute of Technology, Weiqiao-UCAS Science and Technology Park, Binzhou 256606, China;
| | - Haihua Jiao
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (R.L.); (H.J.); (B.S.); (M.S.); (G.Y.); (Z.B.); (X.Z.)
- Department of Biological Sciences and Technology, Changzhi University, Changzhi 046011, China
| | - Bo Sun
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (R.L.); (H.J.); (B.S.); (M.S.); (G.Y.); (Z.B.); (X.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Manjiao Song
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (R.L.); (H.J.); (B.S.); (M.S.); (G.Y.); (Z.B.); (X.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Gaojun Yan
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (R.L.); (H.J.); (B.S.); (M.S.); (G.Y.); (Z.B.); (X.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhihui Bai
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (R.L.); (H.J.); (B.S.); (M.S.); (G.Y.); (Z.B.); (X.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiancheng Wang
- Binzhou Institute of Technology, Weiqiao-UCAS Science and Technology Park, Binzhou 256606, China;
| | - Xuliang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (R.L.); (H.J.); (B.S.); (M.S.); (G.Y.); (Z.B.); (X.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
- Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Qing Hu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (R.L.); (H.J.); (B.S.); (M.S.); (G.Y.); (Z.B.); (X.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
- Xiongan Innovation Institute, Xiongan New Area, Baoding 071000, China
| |
Collapse
|
4
|
Korav S, Yadav DB, Yadav A, Rajanna GA, Parshad J, Tallapragada S, Elansary HO, Mahmoud EA. Rice residue management alternatives in rice-wheat cropping system: impact on wheat productivity, soil organic carbon, water and microbial dynamics. Sci Rep 2024; 14:1822. [PMID: 38245582 PMCID: PMC10799959 DOI: 10.1038/s41598-024-52319-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 01/17/2024] [Indexed: 01/22/2024] Open
Abstract
In the Indo-Gangetic Plains (IGP), rice-wheat cropping system (RWCS) predominates, producing large quantity of crop residue and its management is major concern. Farmers usually burn the residue to clear the field for succeding crop, and burning damages soil microbes, resulted in loss of soil organic matter. Hence, current study was conducted to assess the impact of different Happy seeder based residue management options on changes in microbial dynamics, enzyme activities and soil organic matter content and also to know that alternative method for attaining sustainable wheat productivity in sandy loam soils of Haryana, India. Results revealed that Zero tillage wheat (ZTW) with partial and full residue retention treatments sown with Happy seeder (after using chopper and spreader), and ZTW with anchored stubbles significantly enhanced soil microbial count by 47.9-60.4%, diazotropic count by 59.0-73.1% and actinomycetes count by 47.3-55.2%, grain yield by 9.8-11.3% and biomass yield by 7.4-9.6% over conventional tilled (CT) residue burning and residue removal plots. ZTW sown with surface retention of rice crop residue increased the organic carbon by 0.36-0.42% and the soil moisture content by 13.4-23.6% over CTW without residue load. Similarly, ZTW sown with Happy seeder with full residue enhanced alkaline phosphatase activity from 95.3 µg TPF g-1 soil 24 h-1 in 2018-2019 to 98.6 µg TPF g-1 soil 24 h-1 in 2019-2020 over control plots. Likely, microbial population and enzymatic activity showed strong positive correlation under variable residue retention practices. However, increased microbial population reduced the soil pH from 7.49 to 7.27 under ZTW with residue retention plots. The wheat yield enhanced by 9.8-11.3% during 2018-2019 and 2019-2020 under ZTW with Happy seeder with full residue load over residue burning and residue removal plots. ZTW sown with Happy seeder under full residue retention, achieved maximum net return 43.16-57.08 × 103 ₹ ha-1) and B-C ratio (1.52 to 1.70) over CTW without residue. Therefore, rice residue needs to be managed by planting wheat using appropriate machinery under ZT for sustaining higher productivity in RWCS and improve soil health and environment under IGP regions.
Collapse
Affiliation(s)
- Santosh Korav
- Choudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, 125004, India.
- Department of Agronomy, School of Agriculture, Lovely Professional University (Phagwara) Jalandhar, Punjab, 144411, India.
| | - Dharam Bir Yadav
- Choudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, 125004, India
| | - Ashok Yadav
- Choudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, 125004, India
| | - G A Rajanna
- ICAR-Directorate of Groundnut Research, Junagadh, Gujrat, 362001, India
| | - Jagdish Parshad
- Choudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, 125004, India
| | - Sridevi Tallapragada
- Choudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, 125004, India
| | - Hosam O Elansary
- Plant Production Department, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, 11451, Riyadh, Saudi Arabia
| | - Eman A Mahmoud
- Department of Food Science, Faculty of Agriculture, Damietta University, Damietta, 34511, Egypt
| |
Collapse
|
5
|
Khan MH, Liu H, Zhu A, Khan MH, Hussain S, Cao H. Conservation tillage practices affect soil microbial diversity and composition in experimental fields. Front Microbiol 2023; 14:1227297. [PMID: 37601340 PMCID: PMC10433396 DOI: 10.3389/fmicb.2023.1227297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 07/06/2023] [Indexed: 08/22/2023] Open
Abstract
Introduction Conservation tillage is a widely used technique worldwide, but the effects of conservation tillage on bacterial community structure are poorly understood. We explored proportional alterations in the bacterial community under different tillage treatments. Methodology Hence, this study utilized high-throughput sequencing technique to investigate the structure and assembly processes of microbial communities in different tillage treatments. Results and discussion Tillage treatments included tillage no-straw retention (CntWt), no-tillage with straw retention (CntWntS), tillage with straw retention (CntWtS), no-tillage and no-straw retention (CntWnt). The influence of tillage practices on soil bacterial communities was investigated using Illumina MiSeq sequencing. Different tillage methods and straw retention systems significantly influenced soil parameters such as total potassium and pH were not affected by tillage practices, while straw retention significantly affected soil parameters including nitrogen content, available phosphorus and available potassium. Straw retention decreased bacterial diversity while increased bacterial richness. The effect of straw retention and tillage on bacterial communities was greater than with no tillage. Phylogenetic β-diversity analysis showed that deterministic homogeneous selection processes were dominated, while stochastic processes were more pronounced in tillage without straw retention. Ecological network analysis showed that microbial community correlation was increased in CntWntS and CntWnt. Straw retention treatment significantly increased the relative abundance of bacterial taxa Proteobacteria, Bacteroidetes, and OD1, while Nitrospirae, Actinobacteria, and Verrucomicrobia significantly decreased. Conclusion The conservation tillage practices significantly affect soil properties, bacterial composition, and assembly processes; however, further studies are required to investigate the impact of different crops, tillage practices and physiological characteristics on bacterial community structure and functions.
Collapse
Affiliation(s)
- Muzammil Hassan Khan
- College of Life Sciences/Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Hao Liu
- College of Life Sciences/Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Anning Zhu
- Fengqiu Agro-Ecological Experimental Station, State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| | - Mudassir Hassan Khan
- Department of Biological Sciences, Karakoram International University, Gilgit, Pakistan
| | - Sarfraz Hussain
- College of Life Sciences/Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, China
| | - Hui Cao
- College of Life Sciences/Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| |
Collapse
|
6
|
Liu H, Liu S, Liu H, Liu M, Yin X, Lu P, Hong Q, Liu A, Wan R, Fang S. Revealing the driving synergistic degradation mechanism of Rhodococcus sp. B2 on the bioremediation of pretilachlor-contaminated soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159086. [PMID: 36179826 DOI: 10.1016/j.scitotenv.2022.159086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 09/15/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
The pretilachlor has been widely used worldwide and has contaminated the environment for many years. The environmental fate of pretilachlor and its residues removal from the contaminated environment have attracted great concern. Reportedly, pretilachlor could partly be transformed to HECDEPA by Rhodococcus sp. B2. However, the effects of pretilachlor on soil bacterial communities and its complete metabolic pathway remain unknown. Herein, we investigated the mechanism of driving synergistic degradation of pretilachlor by strain B2 in the soil. The results revealed that pretilachlor showed a negative effect on bacterial communities and caused significant variations in the community structure. Strain B2 showed the ability to remediate the pretilachlor-contaminated soils and network analysis revealed that it may drive the enrichment of potential pretilachlor-degrading bacteria from the soil. The soil pretilachlor degradation may be facilitated by the members of the keystone families Comamonadaceae, Caulobacteraceae, Rhodospirillaceae, Chitinophagaceae, and Sphingomonadaceae. Meanwhile, Sphingomonas sp. M6, a member of the Sphingomonadaceae family, has been isolated from the strain B2 inoculation sample soil. The co-culture, comprising strain M6 and B2, could synergistic degrade pretilachlor within 30 h, which is the highest degradation rate. Strain M6 could completely degrade the HECDEPA via CDEPA and DEA. In the soil, a comparable pretilachlor degradation pathway may exist. This study suggested that strain B2 had the potential to drive the remediation of pretilachlor-contaminated soils.
Collapse
Affiliation(s)
- Hongming Liu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China.
| | - Shiyan Liu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Huijun Liu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Mengna Liu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Xiaye Yin
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Peng Lu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Qing Hong
- Department of Microbiology, Key Lab of Environmental Microbiology for Agriculture, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Aimin Liu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Rui Wan
- School of Ecology and Environment, Anhui Normal University, South of Jiuhua Road, Wuhu, Anhui 241002, China.
| | - Shangping Fang
- School of Anesthesiology, Wannan Medical College, Wuhu, Anhui, China
| |
Collapse
|
7
|
Shi L, Xia P, Lin T, Li G, Wang T, Du X. Temporal Succession of Bacterial Community Structure, Co-occurrence Patterns, and Community Assembly Process in Epiphytic Biofilms of Submerged Plants in a Plateau Lake. MICROBIAL ECOLOGY 2023; 85:87-99. [PMID: 34997308 DOI: 10.1007/s00248-021-01956-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 12/29/2021] [Indexed: 06/14/2023]
Abstract
In shallow macrophytic lakes, epiphytic biofilms are formed on the surface of submerged plant stems and leaves because of algae and bacterial accumulation. Epiphytic biofilms significantly impact the health of the host vegetation and the biogeochemical cycling of lake elements. However, community diversity, species interactions, and community assembly mechanisms in epiphytic bacterial communities (EBCs) of plants during different growth periods are not well understood. We investigated the successional dynamics, co-occurrence patterns, and community assembly processes of epiphytic biofilm bacterial communities of submerged plants, Najas marina and Potamogeton lucens, from July to November 2020. The results showed a significant seasonal variation in EBC diversity and richness. Community diversity and richness increased from July to November, and the temperature was the most important driving factor for predicting seasonal changes in EBC community structure. Co-occurrence network analysis revealed that the average degree and graph density of the network increased from July to November, indicating that the complexity of the EBC network increased. The bacterial community co-occurrence network was limited by temperature, pH, and transparency. The phylogeny-based null model analysis showed that deterministic processes dominated the microbial community assembly in different periods, increasing their contribution. In addition, we found that as the dominance of deterministic processes increased, the microbial co-occurrence links increased, and the potential interrelationships between species became stronger. Thus, the findings provide insights into the seasonal variability of EBC assemblage and co-occurrence patterns in lacustrine ecosystems.
Collapse
Affiliation(s)
- Lei Shi
- Guizhou Province Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, No. 116 Baoshan Road (N), Guiyang, 550001, Guizhou, China
| | - Pinhua Xia
- Guizhou Province Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, No. 116 Baoshan Road (N), Guiyang, 550001, Guizhou, China.
| | - Tao Lin
- Guizhou Province Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, No. 116 Baoshan Road (N), Guiyang, 550001, Guizhou, China
| | - Guoqing Li
- Guizhou Province Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, No. 116 Baoshan Road (N), Guiyang, 550001, Guizhou, China
| | - Tianyou Wang
- Guizhou Province Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, No. 116 Baoshan Road (N), Guiyang, 550001, Guizhou, China
| | - Xin Du
- Guizhou Province Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, No. 116 Baoshan Road (N), Guiyang, 550001, Guizhou, China
| |
Collapse
|
8
|
Chen D, Hou H, Zhou S, Zhang S, Liu D, Pang Z, Hu J, Xue K, Du J, Cui X, Wang Y, Che R. Soil diazotrophic abundance, diversity, and community assembly mechanisms significantly differ between glacier riparian wetlands and their adjacent alpine meadows. Front Microbiol 2022; 13:1063027. [PMID: 36569049 PMCID: PMC9772447 DOI: 10.3389/fmicb.2022.1063027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 11/25/2022] [Indexed: 12/13/2022] Open
Abstract
Global warming can trigger dramatic glacier area shrinkage and change the flux of glacial runoff, leading to the expansion and subsequent retreat of riparian wetlands. This elicits the interconversion of riparian wetlands and their adjacent ecosystems (e.g., alpine meadows), probably significantly impacting ecosystem nitrogen input by changing soil diazotrophic communities. However, the soil diazotrophic community differences between glacial riparian wetlands and their adjacent ecosystems remain largely unexplored. Here, soils were collected from riparian wetlands and their adjacent alpine meadows at six locations from glacier foreland to lake mouth along a typical Tibetan glacial river in the Namtso watershed. The abundance and diversity of soil diazotrophs were determined by real-time PCR and amplicon sequencing based on nifH gene. The soil diazotrophic community assembly mechanisms were analyzed via iCAMP, a recently developed null model-based method. The results showed that compared with the riparian wetlands, the abundance and diversity of the diazotrophs in the alpine meadow soils significantly decreased. The soil diazotrophic community profiles also significantly differed between the riparian wetlands and alpine meadows. For example, compared with the alpine meadows, the relative abundance of chemoheterotrophic and sulfate-respiration diazotrophs was significantly higher in the riparian wetland soils. In contrast, the diazotrophs related to ureolysis, photoautotrophy, and denitrification were significantly enriched in the alpine meadow soils. The iCAMP analysis showed that the assembly of soil diazotrophic community was mainly controlled by drift and dispersal limitation. Compared with the riparian wetlands, the assembly of the alpine meadow soil diazotrophic community was more affected by dispersal limitation and homogeneous selection. These findings suggest that the conversion of riparian wetlands and alpine meadows can significantly alter soil diazotrophic community and probably the ecosystem nitrogen input mechanisms, highlighting the enormous effects of climate change on alpine ecosystems.
Collapse
Affiliation(s)
- Danhong Chen
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming, China
| | - Haiyan Hou
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Shutong Zhou
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Song Zhang
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming, China
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, China
| | - Dong Liu
- Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, School of Life Sciences, Yunnan University, Kunming, China
| | - Zhe Pang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jinming Hu
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming, China
| | - Kai Xue
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jianqing Du
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoyong Cui
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yanfen Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Rongxiao Che
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming, China
| |
Collapse
|
9
|
Pan Q, Huang J, Zhang S, Qin H, Wang X, Mu Y, Tang H, Zhou R. Response of microbiota to exogenous inoculation improved the enzymatic activities of medium-temperature Daqu. Front Microbiol 2022; 13:1047041. [DOI: 10.3389/fmicb.2022.1047041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 10/26/2022] [Indexed: 11/16/2022] Open
Abstract
To explore the potential mechanism of improving enzymatic activities in medium-temperature Daqu (MTD) by inoculation functional isolates, we inoculated a single strain of Bacillus licheniformis, and the microbiota composed of Bacillus velezensis and Bacillus subtilis in MTD to investigate the association between the response of the functional microbiota and the enzymatic activity. The results showed that the bacterial community of MTD might be more sensitive to bioturbation than the fungal community, and the indigenous microbiota responded to the single strain more than to the microbiota. Moreover, the differential microorganisms mainly included Lactobacillales, Bacillales, and Saccharomycetales between the conventional and fortified samples. Notably, the composition of functional microbiota related to liquefying activity (LA) and saccharifying activity (SA) were significantly different, changing from Lactobacillus and Rhizomucor to Bacillus, Weissella, and Hyphopichia. That might be closely related to the effect of the bioturbation on LA (31.33%) and SA (43.54%) associated microorganisms was more tellingly. Furthermore, the relative abundance changes of bioturbation-sensitive modules in the co-occurrence network might also lead to the difference in enzymatic activities. Therefore, the LA and SA of MTD were improved by bioturbation significantly. These results provide diverse insights into the exogenous functional isolates to regulate the MTD microbiota and improve enzymatic activities.
Collapse
|
10
|
Thiebaut F, Urquiaga MCDO, Rosman AC, da Silva ML, Hemerly AS. The Impact of Non-Nodulating Diazotrophic Bacteria in Agriculture: Understanding the Molecular Mechanisms That Benefit Crops. Int J Mol Sci 2022; 23:ijms231911301. [PMID: 36232602 PMCID: PMC9569789 DOI: 10.3390/ijms231911301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 11/16/2022] Open
Abstract
Agriculture is facing increasing challenges with regard to achieving sustainable growth in productivity without negatively impacting the environment. The use of bioinoculants is emerging as a sustainable solution for agriculture, especially bioinoculants based on diazotrophic bacteria. Brazil is at the forefront of studies intended to identify beneficial diazotrophic bacteria, as well as in the molecular characterization of this association on both the bacterial and plant sides. Here we highlight the main advances in molecular studies to understand the benefits brought to plants by diazotrophic bacteria. Different molecular pathways in plants are regulated both genetically and epigenetically, providing better plant performance. Among them, we discuss the involvement of genes related to nitrogen metabolism, cell wall formation, antioxidant metabolism, and regulation of phytohormones that can coordinate plant responses to environmental factors. Another important aspect in this regard is how the plant recognizes the microorganism as beneficial. A better understanding of plant–bacteria–environment interactions can assist in the future formulation of more efficient bioinoculants, which could in turn contribute to more sustainable agriculture practices.
Collapse
|
11
|
Wu Y, Li Y, Niu L, Zhang W, Wang L, Zhang H. Nutrient status of integrated rice-crayfish system impacts the microbial nitrogen-transformation processes in paddy fields and rice yields. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 836:155706. [PMID: 35526617 DOI: 10.1016/j.scitotenv.2022.155706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/30/2022] [Accepted: 05/01/2022] [Indexed: 06/14/2023]
Abstract
Increasing rice yield is essential for alleviating global food crisis. High soil nutrient level guarantees high rice yields in conventional rice monoculture (RM) systems, but excessive unconsumed nutrients act as pollutants and can even threaten rice growth. The integrated rice-crayfish (IRC) system aims to transfer the excess nutrients from crayfish to paddy fields to improve the comprehensive utilization rate of nutrients and create additional profits, while the responding characteristics of IRC microbial communities in paddy fields and rice yields to the nutrient status remain unclear. Considering the crucial roles of microbiomes in promoting nutrient cycling for crop absorption in rice production progresses, the composition and functional characteristics of soil microbial communities from six IRC farms with variant nutrient statuses in the Yangtze River Delta were surveyed in this study. Compared with RM systems, IRC systems with appropriately improved (p < 0.05) soil quality created favorable nutrient (FN) status accompanied by 15% rice yields increase, while IRC systems with extremely high nutrients (HN) status (p < 0.01) accompanied by 14% rice yields reduction. Soil microbial diversity and network complexity were maintained in FN-IRC systems, but declined in HN-IRC systems, with the Shannon index significantly decreased by 9.2% and network density decreased from 0.135 (in RM) to 0.062. In the FN-IRC systems, the keystone taxa identified by co-occurrence networks displayed inextricably positive correlations with soil nitrification potential (calculated by normalization of amoA gene abundance) and rice yields. While in HN-IRC systems, the large loss of keystone taxa might limit soil nitrogen fixation potential (calculated by normalization of nifH gene abundance), and further rice yields. Our study indicates that soil nutrient management in IRC systems claim attention, and the improvement of nitrogen metabolism is the key to realize agricultural cleaner production.
Collapse
Affiliation(s)
- Yunyu Wu
- College of Hydrology and Water Resources, Hohai University, Nanjing 210098, PR China
| | - Yi Li
- College of Hydrology and Water Resources, Hohai University, Nanjing 210098, PR China
| | - Lihua Niu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
| | - Wenlong Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
| | - Longfei Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
| | - Huanjun Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
| |
Collapse
|
12
|
Ladha JK, Peoples MB, Reddy PM, Biswas JC, Bennett A, Jat ML, Krupnik TJ. Biological nitrogen fixation and prospects for ecological intensification in cereal-based cropping systems. FIELD CROPS RESEARCH 2022; 283:108541. [PMID: 35782167 PMCID: PMC9133800 DOI: 10.1016/j.fcr.2022.108541] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 03/29/2022] [Accepted: 04/03/2022] [Indexed: 05/02/2023]
Abstract
The demand for nitrogen (N) for crop production increased rapidly from the middle of the twentieth century and is predicted to at least double by 2050 to satisfy the on-going improvements in productivity of major food crops such as wheat, rice and maize that underpin the staple diet of most of the world's population. The increased demand will need to be fulfilled by the two main sources of N supply - biological nitrogen (gas) (N2) fixation (BNF) and fertilizer N supplied through the Haber-Bosch processes. BNF provides many functional benefits for agroecosystems. It is a vital mechanism for replenishing the reservoirs of soil organic N and improving the availability of soil N to support crop growth while also assisting in efforts to lower negative environmental externalities than fertilizer N. In cereal-based cropping systems, legumes in symbiosis with rhizobia contribute the largest BNF input; however, diazotrophs involved in non-symbiotic associations with plants or present as free-living N2-fixers are ubiquitous and also provide an additional source of fixed N. This review presents the current knowledge of BNF by free-living, non-symbiotic and symbiotic diazotrophs in the global N cycle, examines global and regional estimates of contributions of BNF, and discusses possible strategies to enhance BNF for the prospective benefit of cereal N nutrition. We conclude by considering the challenges of introducing in planta BNF into cereals and reflect on the potential for BNF in both conventional and alternative crop management systems to encourage the ecological intensification of cereal and legume production.
Collapse
Affiliation(s)
- Jagdish K. Ladha
- Department of Plant Sciences, University of California, Davis, CA, USA
| | - Mark B. Peoples
- Commonwealth Scientific and Industrial Research Organisation, Canberra, Australia
| | | | | | - Alan Bennett
- Department of Plant Sciences, University of California, Davis, CA, USA
| | - Mangi L. Jat
- International Maize and Wheat Improvement Center, New Delhi, India
| | | |
Collapse
|
13
|
Chen S, Wang L, Gao J, Zhao Y, Wang Y, Qi J, Peng Z, Chen B, Pan H, Wang Z, Gao H, Jiao S, Wei G. Agricultural Management Drive Bacterial Community Assembly in Different Compartments of Soybean Soil-Plant Continuum. Front Microbiol 2022; 13:868307. [PMID: 35602087 PMCID: PMC9114711 DOI: 10.3389/fmicb.2022.868307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 03/28/2022] [Indexed: 12/02/2022] Open
Abstract
Flowering stage of soybean is an important agronomic trait, which is important for soybean yield, quality and adaptability, and is the external expression of integrating external environmental factors and endogenous signals of the plant itself. Cropping system can change soil properties and fertility, which in turn determine plant growth and yield. The microbial community is the key regulator of plant health and production performance. Currently, there is limited understanding of the effects of cropping systems on microbial community composition, ecological processes controlling community assembly in different soil-plant continuum compartments of soybean. Here, we hope to clarify the structure and assembly process of different soybean compartments bacterial community at flowering stage through our work. The results showed that intercropping decreased the species diversity of rhizosphere and phyllosphere, and phylloaphere microbes mainly came from rhizosphere. FAPROTAX function prediction showed that indicator species sensitive to intercropping and crop rotation were involved in nitrogen/phosphorus cycle and degradation process, respectively. In addition, compared to the continuous cropping, intercropping increased the stochastic assembly processes of bacterial communities in plant-associated compartments, while crop rotation increased the complexity and stability of the rhizosphere network and the deterministic assembly process. Our study highlights the importance of intercropping and crop rotation, as well as rhizosphere and phyllosphere compartments for future crop management and sustainable agricultural regulation of crop microbial communities.
Collapse
Affiliation(s)
- Shi Chen
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Lulu Wang
- Suzhou Academy of Agricultural Sciences, Suzhou, China
| | - Jiamin Gao
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Yiwen Zhao
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Yang Wang
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Jiejun Qi
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Ziheng Peng
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Beibei Chen
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Haibo Pan
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Zhifeng Wang
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Hang Gao
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Shuo Jiao
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| | - Gehong Wei
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China
| |
Collapse
|
14
|
Zhang C, Liu H, Liu S, Hussain S, Zhang L, Yu X, Cao K, Xin X, Cao H, Zhu A. Response of Fungal Sub-Communities in a Maize-Wheat Rotation Field Subjected to Long-Term Conservation Tillage Management. Front Microbiol 2022; 13:829152. [PMID: 35422775 PMCID: PMC9002332 DOI: 10.3389/fmicb.2022.829152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 02/08/2022] [Indexed: 11/13/2022] Open
Abstract
Conservation tillage is an advanced agricultural technology that seeks to minimize soil disturbance by reducing, or even eliminating tillage. Straw or stubble mulching in conservation tillage systems help to increase crop yield, maintain biodiversity and increase levels of exogenous nutrients, all of which may influence the structure of fungal communities in the soil. Currently, however, the assembly processes and co-occurrence patterns of fungal sub-communities remain unknown. In this paper, we investigated the effects of no-tillage and straw mulching on the composition, assembly process, and co-occurrence patterns of soil fungal sub-communities in a long-term experimental plot (15 years). The results revealed that combine straw mulching with no-tillage significantly increased the richness of fungi but not their diversity. Differential abundance analysis and principal component analysis (PCA) indicated that tillage management had a greater effect on the fungal communities of abundant and intermediate taxa than on the rare taxa. Available phosphorus (AP) and total nitrogen (TN) were the major determinants of fungal sub-communities in NT treatment. The abundant fungal sub-communities were assembled by deterministic processes under medium strength selection, while strong conservation tillage strength shifts the abundant sub-community assembly process from deterministic to stochastic. Overall, the investigation of the ecological network indicated that no-tillage and straw mulching practices decreased the complexity of the abundant and intermediate fungal networks, while not significantly influencing rare fungal networks. These findings refine our knowledge of the response of fungal sub-communities to conservation tillage management techniques and provide new insights into understanding fungal sub-community assembly.
Collapse
Affiliation(s)
- Cunzhi Zhang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Hao Liu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Senlin Liu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Sarfraz Hussain
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China.,Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, China
| | - Liting Zhang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Xiaowei Yu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Kaixun Cao
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Xiuli Xin
- Fengqiu Agro-Ecological Experimental Station, State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| | - Hui Cao
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Anning Zhu
- Fengqiu Agro-Ecological Experimental Station, State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| |
Collapse
|
15
|
Bacterial Communities in the Rhizosphere at Different Growth Stages of Maize Cultivated in Soil Under Conventional and Conservation Agricultural Practices. Microbiol Spectr 2022; 10:e0183421. [PMID: 35254138 PMCID: PMC9049951 DOI: 10.1128/spectrum.01834-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Farmers in Mexico till soil intensively, remove crop residues for fodder and grow maize often in monoculture. Conservation agriculture (CA), including minimal tillage, crop residue retention and crop diversification, is proposed as a more sustainable alternative. In this study, we determined the effect of agricultural practices and the developing maize rhizosphere on soil bacterial communities. Bulk and maize (Zea mays L.) rhizosphere soil under conventional practices (CP) and CA were sampled during the vegetative, flowering and grain filling stage, and 16S rRNA metabarcoding was used to assess bacterial diversity and community structure. The functional diversity was inferred from the bacterial taxa using PICRUSt. Conservation agriculture positively affected taxonomic and functional diversity compared to CP. The agricultural practice was the most important factor in defining the structure of bacterial communities, even more so than rhizosphere and plant growth stage. The rhizosphere enriched fast growing copiotrophic bacteria, such as Rhizobiales, Sphingomonadales, Xanthomonadales, and Burkholderiales, while in the bulk soil of CP other copiotrophs were enriched, e.g., Halomonas and Bacillus. The bacterial community in the maize bulk soil resembled each other more than in the rhizosphere of CA and CP. The bacterial community structure, and taxonomic and functional diversity in the maize rhizosphere changed with maize development and the differences between the bulk soil and the rhizosphere were more accentuated when the plant aged. Although agricultural practices did not alter the effect of the rhizosphere on the soil bacterial communities in the flowering and grain filling stage, they did in the vegetative stage. IMPORTANCE We studied the effect of sustainable conservation agricultural practices versus intensive conventional ones on the soil microbial diversity, potential functionality, and community assembly in rhizosphere of maize cultivated in a semiarid environment. We found that conservation agriculture practices increased the diversity of soil microbial species and functions and strongly affected how they were structured compared to conventional practices. Microbes affected by the roots of maize, the rhizobiome, were different and more diverse than in the surrounding soil and their diversity increased when the plant grew. The agricultural practices affected the maize rhizobiome only in the early stages of growth, but this might have an important impact on the development of maize plant.
Collapse
|