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Rattan Lal - One of the best experts on this subject based on the ideXlab platform.
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effect of cropping systems in no till Farming on the quality of a brazilian oxisol
Revista Brasileira De Ciencia Do Solo, 2014Co-Authors: Getulio De Freitas Seben, Jose Eduardo Cora, Rattan LalAbstract:The No-Till system with complex cropping sequences may improve the structural quality and carbon (C) sequestration in soils of the tropics. Thus, the objective of this study was to evaluate the effects of cropping sequences after eight years under the No-Till system on the physical properties and C sequestration in an Oxisol in the municipality of Jaboticabal, Sao Paulo, Brazil. A randomized split-block design with three replications was used. The treatments were combinations of three summer cropping sequences - corn/corn (Zea mays L.) (CC), soybean/soybean (Glycine max L. Merryll) (SS), and soybean-corn (SC); and seven winter crops - corn, sunflower (Helianthus annuus L.), oilseed radish (Raphanus sativus L.), pearl millet (Pennisetum americanum (L.) Leeke), pigeon pea (Cajanus cajan (L.) Millsp), grain sorghum (Sorghum bicolor (L.) Moench), and sunn hemp (Crotalaria juncea L.). Soil samples were taken at the 0-10 cm depth after eight years of experimentation. Soil under SC and CC had higher mean weight diameter (3.63 and 3.55 mm, respectively) and geometric mean diameter (3.55 and 2.92 mm) of the aggregates compared to soil under SS (3.18 and 2.46 mm). The CC resulted in the highest soil organic C content (17.07 g kg-1), soil C stock (15.70 Mg ha-1), and rate of C sequestration (0.70 Mg ha-1 yr-1) among the summer crops. Among the winter crops, soil under pigeon pea had the highest total porosity (0.50 m3 m-3), and that under sunn hemp had the highest water stable aggregates (93.74 %). In addition, sunn hemp did not differ from grain sorghum and contained the highest soil organic C content (16.82 g kg-1) and also had the highest rate of C sequestration (0.67 Mg ha-1 yr-1). The soil resistance to penetration was the lower limit of the least limiting water range, while the upper limit was air-filled porosity for soil bulk densities higher than 1.39 kg dm-3 for all cropping sequences. Within the SC sequence, soil under corn and pigeon pea increased least limiting water range by formation of biopores because soil resistance to penetration decreased with the increase in soil bulk density.
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enhancing eco efficiency in agro ecosystems through soil carbon sequestration
Crop Science, 2010Co-Authors: Rattan LalAbstract:Global cereal production must be increased by ∼50% by 2050. Crop yields in sub-Saharan Africa and South Asia have either stagnated or declined since the 1990s because of the widespread use of extractive Farming practices and problems of soil and environmental degradation. Yield potential of improved varieties and elite germplasm is not realized because of soil degradation. The concept of eco-efficiency implies efficient and sustainable use of resources in agronomic production and soil management. However, it is not enough to merely minimize the environmental impact. It is also important to maximize agronomic production while enhancing ecosystem services. Most degraded and depleted soils of agro-ecosystems contain a lower soil organic carbon (SOC) pool than in those under natural ecosystems. Thus, restoring the SOC pool is essential to improving soil quality, increasing eco-efficiency, and enhancing numerous ecosystem services. Increasing the SOC pool in the root zone can enhance agronomic production (kg grains ha⁻¹ Mg C⁻¹) at the rate of 200 to 300 for maize (Zea mays L.), 30 to 60 for bean (Phaseolis vulgaris L.), 20 to 40 for wheat (Triticum aestivum L.), 20 to 50 for soybean [Glycine max (L.) Merr.], and 20 to 50 for rice (Oryza sativa L.). Not all improved management practices are applicable to all soil and ecological conditions. However, No-Till Farming along with application of crop residue mulch, manuring, legume-based complex rotations, and integrated nutrient management should be applicable under most conditions. Global food insecurity, affecting 1.02 billion people in 2009, can only be alleviated by improving soil quality and eco-efficiency through restoration of degraded/depleted soils.
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challenges and opportunities in soil organic matter research
European Journal of Soil Science, 2009Co-Authors: Rattan LalAbstract:Summary Soil organic matter (SOM) can be a source or sink for atmospheric CO2 depending on land use, and management of soil, vegetation and water resources. SOM is a source of atmospheric CO2 ,w ith the use of extractive Farming practices that lead to a negative nutrient balance and exacerbate soil degradation. The historic loss of C from the SOM pool between the 1850s and 2000 is estimated at 78 � 12 Gt compared with the emission of 270 � 30 Gt from fossil fuel combustion. Despite its numerous direct and ancillary benefits, enhancing the SOM pool is a major challenge, especially in impoverished and depleted soils in harsh tropical climates. In addition to biophysical factors, there are also numerous social, economic and political constraints that limit increase in SOM pools. Conversion of plough-tillage to No-Till Farming, an important practice to enhance the SOM pool, is constrained by the limited access to herbicides and seed drill, and the competing uses of crop residues. Yet, enhancing the SOM pool is essential to restoring degraded soils, advancing food security and improving the environment. Important subjects among researchable topics include: assessing the rate of SOM accretion for a wide range of land use and management practices with reference to a baseline; evaluating the importance of biochar; measuring and predicting SOM at landscape and extrapolation to regional scale; establishing relationships between SOM and soil quality and agronomic productivity; determining on- and off-site effects of crop residues removal for ethanol/biofuel production; determining the fate of C in SOM translocated by erosional processes; evaluating nutrient requirements for increasing SOM in croplands; validating predictive models in tropical environments; and developing methodology for trading C credits.
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principles of soil conservation and management
2008Co-Authors: Humberto Blanco, Rattan LalAbstract:Preface Foreword 1 SOIL AND WATER CONSERVATION 1.1. Why Conserve Soil? 1.2. Agents that Degrade Soil 1.3. Soil Erosion 1.4. History of Soil Erosion 1.5. Consequences of Soil Erosion 1.6. Drivers of Soil Erosion 1.7. Erosion in the USA 1.8. Global Distribution of Soil Erosion 1.9. Current Trends in Soil and Water Conservation Summary Study Questions References 2 WATER EROSION 2.2. Types 2.3. Processes 2.4. Factors 2.5. Agents 2.6. Rainfall Erosivity 2.7. Runoff Erosivity 2.8. Soil Properties Affecting Erodibility 2.9. Measuring Erosion Summary Study Questions References 3 WIND EROSION 3.1. Processes 3.2. Factors 3.3. Wind Erosivity 3.4. Soil Erodibility 3.5. Measuring Wind Erosion 3.6. Management of Wind Erosion 3.7. Windbreaks 3.8. Crop Residues 3.9. Perennial Grasses 3.10. Conservation Tillage Summary Study Questions References 4 MODELING WATER AND WIND EROSION 4.1. Modeling Erosion 4.2. Empirical Models 4.3. Universal Soil Loss Equation (USLE) 4.4. Modified USLE (MUSLE) 4.5. Revised USLE (RUSLE): 4.6. Process-Based Models 4.7. Water Erosion Prediction Project (WEPP) 4.8. Ephemeral Gully Erosion Model (EGEM) 4.9. Other Water Erosion Models 4.10. Modeling Wind Erosion 4.11. Wind Erosion Equation (WEQ) 4.12. Revised WEQ (RWEQ) 4.13. Process-Based Models 4.14. Wind Erosion Prediction System (WEPS) 4.15. Other Wind Erosion Models 4.16. Limitations of Water and Wind Models Summary Study Questions References 5 TILLAGE EROSION 5.1. Definition and Magnitude of the Problem 5.2. Tillage Erosion Research: Past and Present 5.3. Tillage Erosion versus Water and Wind Erosion 5.4. Factors Affecting Tillage Erosion 5.5. Landform Erodibility 5.6. Soil Erodibility 5.7. Tillage Erosivity 5.8. Tillage Erosion and Soil Properties 5.9. Indicators of Tillage Erosion 5.10. Measurement of Soil Displacement 5.11. Tillage Erosion and Crop Production 5.12. Management of Tillage Erosion 5.13. Tillage Erosion Modeling 5.14. Predictive Equations 5.15. Computer Models 5.16. Soil Erosion and Crop Harvesting Summary Study Questions References 6 BIOLOGICAL MEASURES OF EROSION CONTROL 6.1. Functions of Canopy Cover 6.2. Soil Amendments 6.3. Cover Crops 6.4. Crop Residues 6.5. Residue Harvesting for Biofuel Production 6.6. Bioenergy Plantations as an Alternative to Crop Residue Removal 6.7. Manuring 6.8. Soil Conditioners: Polymers 6.9. Polyacrylamides Summary Study Questions References 7 CROPPING SYSTEMS 7.1. Fallow Systems 7.2. Summer Fallows 7.3. Monoculture 7.4. Crop Rotations 7.5. Cover Crops 7.6. Cropping Intensity 7.7. Row Crops 7.8. Multiple Cropping 7.9. Double Cropping 7.10. Relay Cropping 7.11. Intercropping 7.12. Contour Farming 7.13. Strip Cropping 7. 14. Contour Strip Cropping 7.15. Land Equivalent Ratio 7.16. Organic Farming Summary Study Questions References 8 No-Till Farming 8.1. Seedbed and Soil Tilth 8.2. Factors Affecting Soil Tilth 8.3. Tilth Index 8.4. Tillage 8.5. Tillage Tools 8.6. Types of Tillage Systems 8.7. Conventional Tillage: Moldboard Plowing 8.8. Conservation Tillage Systems 8.9. No-Till Farming 8.10. Benefits of No-Till Farming 8.11. Challenges in No-Till Management 8.12. No-Till and Subsoiling 8.13. Reduced Tillage 8.14. Mulch Tillage 8.15. Strip Tillage 8.16. Ridge Tillage Summary Study Questions References 9 BUFFER STRIPS 9.1. Importance 9.2. Mechanisms of Pollutant Removal 9.3. Factors Influencing the Performance of Buffer Strips 9.4. Types and Management 9.5. Riparian Buffer Strips 9.6. Filters Strips 9.7. Grass Barriers 9.8. Grass Waterways 9.9. Field Borders 9.10. Modeling of Sediment Transport through Buffer Strips Summary Study Questions References 10 AGROFORESTRY 10.1. Importance 10.2. Classification 10.3. History 10.4. Current Trends 10.5. Functions of Agroforestry 10.6. Agroforestry and Factors of Soil Erosion 10.7. Agroforestry and Land Rec
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managing soil carbon
Science, 2004Co-Authors: Rattan Lal, Michael Griffin, Jay Apt, Lester B Lave, Granger M MorganAbstract:Current Farming practices deplete soil carbon, which degrades soil quality, reduces productivity, and results in the need for more fertilization, irrigation, and pesticides. No-Till Farming with residue mulching would reverse these effects by slowing soil erosion and pollution runoff, benefiting aquatic ecosystems, improving agronomic productivity, and achieving food security. The authors of this Policy Forum urge support for its wider use. Although there may be short-term yield reductions in some soils and climates, this is a win-win opportunity for the vast majority of the 95% of the cropland that does not use these more sustainable practices.
Andreas Gattinger - One of the best experts on this subject based on the ideXlab platform.
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Agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
The ISME Journal, 2019Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G. A. HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, No-Till, and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harbored a much more complex fungal network with significantly higher connectivity than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. We also found a strong negative association ( R ^2 = 0.366; P
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agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
The ISME Journal, 2019Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G A Van Der HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, No-Till, and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harbored a much more complex fungal network with significantly higher connectivity than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. We also found a strong negative association (R2 = 0.366; P < 0.0001) between agricultural intensification and root fungal network connectivity. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH, and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic Farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiome.
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Agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
2018Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G A Van Der HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences network complexity of microbial communities. We investigated the impact of conventional, No-Till and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harboured a much more complex fungal network than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic Farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiota.
Samiran Banerjee - One of the best experts on this subject based on the ideXlab platform.
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Agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
The ISME Journal, 2019Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G. A. HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, No-Till, and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harbored a much more complex fungal network with significantly higher connectivity than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. We also found a strong negative association ( R ^2 = 0.366; P
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agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
The ISME Journal, 2019Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G A Van Der HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, No-Till, and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harbored a much more complex fungal network with significantly higher connectivity than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. We also found a strong negative association (R2 = 0.366; P < 0.0001) between agricultural intensification and root fungal network connectivity. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH, and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic Farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiome.
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Agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
2018Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G A Van Der HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences network complexity of microbial communities. We investigated the impact of conventional, No-Till and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harboured a much more complex fungal network than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic Farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiota.
Marcel G A Van Der Heijden - One of the best experts on this subject based on the ideXlab platform.
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agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
The ISME Journal, 2019Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G A Van Der HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, No-Till, and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harbored a much more complex fungal network with significantly higher connectivity than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. We also found a strong negative association (R2 = 0.366; P < 0.0001) between agricultural intensification and root fungal network connectivity. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH, and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic Farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiome.
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Agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
2018Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G A Van Der HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences network complexity of microbial communities. We investigated the impact of conventional, No-Till and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harboured a much more complex fungal network than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic Farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiota.
Florian Walder - One of the best experts on this subject based on the ideXlab platform.
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Agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
The ISME Journal, 2019Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G. A. HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, No-Till, and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harbored a much more complex fungal network with significantly higher connectivity than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. We also found a strong negative association ( R ^2 = 0.366; P
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agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
The ISME Journal, 2019Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G A Van Der HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, No-Till, and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harbored a much more complex fungal network with significantly higher connectivity than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. We also found a strong negative association (R2 = 0.366; P < 0.0001) between agricultural intensification and root fungal network connectivity. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH, and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic Farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiome.
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Agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots
2018Co-Authors: Samiran Banerjee, Florian Walder, Lucie Buchi, Marcel Meyer, Alain Y Held, Andreas Gattinger, Thomas Keller, Raphael Charles, Marcel G A Van Der HeijdenAbstract:Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different Farming systems on the root microbiota and it is still unclear whether agricultural intensification influences network complexity of microbial communities. We investigated the impact of conventional, No-Till and organic Farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic Farming harboured a much more complex fungal network than conventional and No-Till Farming systems. The abundance of keystone taxa was the highest under organic Farming where agricultural intensification was the lowest. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic Farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiota.