Cropping management in a livestock‐pasture‐crop integration modifies microbial communities, activity, and soil health score

Soil microorganisms play an important role as a link in the transfer of nutrients from the rhizosphere. The physical and chemical properties of soil, the metabolic profiles of microbial communities and different crop management practices can enhance our understanding of hizospheric interactions. This study aimed to establish differences in microbial communities associated with banana crops and the biochemical profile in farms under different agronomic conditions. Seven farms with different levels of intervention, management, and fusariosis severity were analyzed. The biochemical profile of the microbial community was determined using EcoPlates and the main substrates consumed by the microbial communities were identified through multivariate principal component analysis (PCA). Seven microorganisms were selected as indicators of nutrient cycles, pathogenicity and soil health. Also, soil chemical indicators were determined through a complete mineral analysis. For the physiological profile of soil microbial populations, it was observed that farms with the same management tend to be metabolically very similar. In the PCA, two principal components explained 90 % of the variance in the data. It was also determined that the genus Bacillus is predominant in all farms and that farm 4 (medium intervention) presented the most favorable values in all factors analyzed. The effective cation exchange capacity values are highlighted in the chemical analyses, which determined that all farms have a high fertility level. The metabolic profile, diversity and richness of each of the different farms were affected by the type of agronomic management used.

Download Full-text

Soil Microbial Activity and Diversity in Response to Soil Chemical Factors in Agricultural Soils

Journal of Tropical Soils ◽

10.5400/jts.2019.v24i1.43-51 ◽

2019 ◽

Vol 24 (1) ◽

pp. 43

Author(s):

Lily Ishak ◽

Philip Hugh Brown

Keyword(s):

Microbial Communities ◽

Agricultural Soils ◽

Soil Health ◽

Soil Microbial Communities ◽

Soil Microbial Activity ◽

Soil Microbial Diversity ◽

Soil Microbial ◽

Microbial Responses ◽

Chemical Factors ◽

Microbial Groups

The role of microbial communities in maintaining soil health is mostly influenced by chemical condition of soil. Microbial communities vary in response to soil chemical factors. The contradictive results from previous findings emphasise that it is difficult to define a pattern of the influence of soil chemical factors on soil microbial diversity and activity. The aim of the study was to assess soil microbial responses to soil chemical factors in agricultural soils. Composite soil (Dermosol order) samples taken from 16 commercial crop sites in Bundaberg, Queensland, Australia, were chemically and biologically analysed. It was found that bacterial and fungal activity and diversity were significantly affected by soil EC, SOM and NO3-N content, but were not influenced by soil pH, CEC, and Ca:Mg ratio. The diversity of bacterial and fungal communities displayed a positive linear relationship with soil EC, whereas the activity and diversity of these two microbial groups and SOM displayed a significant quadratic relationship. The finding suggested that microbial community was predominantly influenced by SOM content.

Download Full-text

Extreme drought triggers transition to an alternative soil microbial state

10.1101/2021.12.10.472086 ◽

2021 ◽

Author(s):

Irene Cordero ◽

Ainara Leizeaga ◽

Lettice C Hicks ◽

Johannes Rousk ◽

Richard D Bardgett

Keyword(s):

Microbial Communities ◽

Bacterial Communities ◽

Soil Health ◽

Soil Microbial Communities ◽

Climate Extremes ◽

Extreme Drought ◽

Alternative States ◽

Soil Microbial ◽

Fungal Community Structure ◽

Functional States

Soil microbial communities play a pivotal role in regulating ecosystem functioning but they are increasingly threatened by human-driven perturbations, including climate extremes, which are predicted to increase in frequency and intensity with climate change. It has been demonstrated that soil microbial communities are sensitive to climate extremes, such as drought, and that effects can be long-lasting. However, considerable uncertainties remain concerning the response of soil microbial communities to increases in the intensity and frequency of climate extremes, and their potential to trigger transitions to alternative, and potentially deleterious, taxonomic and functional states. Here we demonstrate that extreme, frequent drought induces a shift to an alternative soil microbial state characterised by strongly altered bacterial and fungal community structure of reduced complexity and functionality. Moreover, we found that this drought-induced alternative microbial state persisted after returning soil to its previous moisture status. However, bacterial communities were able to adapt by increasing their growth capacity, despite being of reduced diversity. Abrupt transitions to alternative states are well documented in aquatic and terrestrial plant communities in response to human-induced perturbations, including climate extremes. Our results provide experimental evidence that such transitions also occur in soil microbial communities in response to extreme drought with potentially deleterious consequences for soil health.

Download Full-text

Effect of Fungicide Application on Lowbush Blueberries Soil Microbiome

Microorganisms ◽

10.3390/microorganisms9071366 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1366

Author(s):

Austin W. Lloyd ◽

David Percival ◽

Svetlana N. Yurgel

Keyword(s):

Microbial Communities ◽

Combined Treatment ◽

Soil Health ◽

Cropping System ◽

Soil Nutrient ◽

Amplicon Sequencing ◽

Soil Microbiome ◽

Nutrient Cycles ◽

Eastern Canada ◽

The Impact

Lowbush blueberries (Vaccinium sp.) are perennial crops produced throughout eastern Canada and Maine through management of wild populations. Given the constraints of this cropping system, the application of fungicides is critical to reducing disease pressure and ensuring consistent yields. However, as plant health is intertwined with soil health, it is important to consider the impact of fungicides on microbial communities. To understand the effects of fungicides in this context, bacterial and fungal microbial communities from fungicide-treated plots, as well as untreated control plots (UTG) were analyzed using amplicon sequencing. The fungicides, considered collectively as a combined treatment group (CTG), lead to a loss in fungal richness. One family, Clavariaceae, had an increased abundance under prothioconazole relative to UTG. This finding may be significant as taxa in Clavariaceae have been thought to potentially form ericoid mycorrhizae with Vaccinium. Five functional pathways and 74 enzymes differed significantly in relative abundance between CTG and UTG including enzymes associated with soil nutrient cycles. Most notably, enzymes corresponding to the breakdown of halogen-organic compounds had an increased abundance in CTG, suggesting bacterial fungicide degradation. Some enzymes associated with soil nutrient cycles differed significantly, possibly implying changes to nutrient pathways due to fungicide treatment.

Download Full-text

Irreplaceable Role of Amendment-Based Strategies to Enhance Soil Health and Disease Suppression in Potato Production

Microorganisms ◽

10.3390/microorganisms9081660 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1660

Author(s):

Jianjun Hao ◽

Katherine Ashley

Keyword(s):

Microbial Communities ◽

Soil Microorganisms ◽

Soil Amendments ◽

Soil Health ◽

Soil Microbial Communities ◽

Potato Production ◽

Disease Suppression ◽

Plant Health ◽

Soilborne Pathogens ◽

Health And Disease

Soilborne diseases are a major constraining factor to soil health and plant health in potato production. In the toolbox of crop management, soil amendments have shown benefits to control these diseases and improve soil quality. Most amendments provide nutrients to plants and suppress multiple soilborne pathogens. Soil amendments are naturally derived materials and products and can be classified into fresh or living plants, organic or inorganic matters, and microbial supplements. Fresh plants have unique functions and continuously exude chemicals to interact with soil microbes. Organic and inorganic matter contain high levels of nutrients, including nitrogen and carbon that plants and soil microorganisms need. Soil microorganisms, whether being artificially added or indigenously existing, are a key factor in plant health. Microbial communities can be considered as a biological reactor in an ecosystem, which suppress soilborne pathogens in various mechanisms and turn soil organic matter into absorbable forms for plants, regardless of amendment types. Therefore, soil amendments serve as an energy input, nutrient source, and a driving force of microbial activities. Advanced technologies, such as microbiome analyses, make it possible to analyze soil microbial communities and soil health. As research advances on mechanisms and functions, amendment-based strategies will play an important role in enhancing soil health and disease suppression for better potato production.

Download Full-text

Rhizosphere Microbial Communities Are Significantly Affected by Optimized Phosphorus Management in a Slope Farming System

Frontiers in Microbiology ◽

10.3389/fmicb.2021.739844 ◽

2021 ◽

Vol 12 ◽

Author(s):

Qianxin Deng ◽

Tong Zhang ◽

Deti Xie ◽

Yuheng Yang

Keyword(s):

Microbial Communities ◽

Soil Health ◽

Soil Microbial Communities ◽

Growth Period ◽

Farming System ◽

Environmental Drivers ◽

Growth Stages ◽

P Fertilization ◽

Soil Microbial ◽

Use Efficiency

Soil rhizosphere microorganisms play crucial roles in promoting plant nutrient absorption and maintaining soil health. However, the effects of different phosphorus (P) managements on soil microbial communities in a slope farming system are poorly understood. Here, rhizosphere microbial communities under two P fertilization levels—conventional (125 kg P2O5 ha–1, P125) and optimal (90 kg P2O5 ha–1, P90)—were compared at four growth stages of maize in a typical sloped farming system. The richness and diversity of rhizosphere bacterial communities showed significant dynamic changes throughout the growth period of maize, while different results were observed in fungal communities. However, both the P fertilization levels and the growth stages influenced the structure and composition of the maize rhizosphere microbiota. Notably, compared to P125, Pseudomonas, Conexibacter, Mycobacterium, Acidothermus, Glomeromycota, and Talaromyces were significantly enriched in the different growth stages of maize under P90, while the relative abundance of Fusarium was significantly decreased during maize harvest. Soil total nitrogen (TN) and pH are the first environmental drivers of change in bacterial and fungal community structures, respectively. The abundance of Gemmatimonadota, Proteobacteria, and Cyanobacteria showed significant correlations with soil TN, while that of Basidiomycota and Mortierellomycota was significantly related to pH. Additionally, P90 strengthened the connection between bacteria, but reduced the links between fungi at the genus level. Our work helps in understanding the role of P fertilization levels in shaping the rhizosphere microbiota and may manipulate beneficial microorganisms for better P use efficiency.

Download Full-text

Response of Soil Properties and Microbial Communities to Agriculture: Implications for Primary Productivity and Soil Health Indicators

Frontiers in Plant Science ◽

10.3389/fpls.2016.00990 ◽

2016 ◽

Vol 7 ◽

Cited By ~ 76

Author(s):

Pankaj Trivedi ◽

Manuel Delgado-Baquerizo ◽

Ian C. Anderson ◽

Brajesh K. Singh

Keyword(s):

Soil Properties ◽

Microbial Communities ◽

Primary Productivity ◽

Soil Health ◽

Health Indicators

Download Full-text

Effects of Bacillus subtilis and Pseudomonas fluorescens Inoculation on Attributes of the Lettuce (Lactuca sativa L.) Soil Rhizosphere Microbial Community: The Role of the Management System

Agronomy ◽

10.3390/agronomy10091428 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1428

Author(s):

Eirini Angelina ◽

Efimia M. Papatheodorou ◽

Triantafyllia Demirtzoglou ◽

Nikolaos Monokrousos

Keyword(s):

Bacillus Subtilis ◽

Microbial Communities ◽

Pseudomonas Fluorescens ◽

Lactuca Sativa ◽

Management System ◽

Soil Health ◽

Soil Microbial Communities ◽

Root Weight ◽

Soil Microbial ◽

Microbial Inoculation

Inoculation with beneficial microbes has been proposed as an effective practice for the improvement of plant growth and soil health. Since soil acts as a physicochemical background for soil microbial communities, we hypothesized that its management will mediate the effects of microbial inoculants on the indigenous soil microbes. We examined the effects of bacterial inoculants [Bacillus subtilis (Ba), Pseudomonas fluorescens (Ps), and both (BaPs)] on the growth of Lactuca sativa cultivated in soils that originated from an organic maize (OS) and a conventional barley (CS) management system. Moreover, the biomass and the community structure of the rhizosphere microbial communities and the soil enzyme activities were recorded. The root weight was higher in CS than OS, while the foliage length was greater in OS than CS treatments. Only in OS pots, inoculants resulted in higher biomasses of bacteria, fungi, and actinomycetes compared to the control with the highest values being recorded in Ps and BaPs treated soils. Furthermore, different inoculants resulted in different communities in terms of structure mainly in OS soils. For soil enzymes, the effect of the management system was more important due to the high organic matter existing in OS soils. We suggest that for microbial inoculation to be effective it should be considered together with the management history of the soil.

Download Full-text