Discover insights from thousands of peer-reviewed papers on microbial electrochemical systems
T. Imai, H. Vo, M. Fukushima et al.
Water · 2022
Localized biogenic corrosion and extrication of annoying odors caused by hydrogen sulfide (H2S) have long been a big problem in the management of urban sewer systems. H2S emission control in sewers via chemically or biologically normal oxidation processes has also been investigated extensively and is costly. The objective of this work was to develop a new technology to mitigate the concentration of H2S in sewer pipes using conductive concrete. Experimental results after 66 days show that the concentration of hydrogen sulfide significantly decreased when conductive concrete was used as a microbial fuel cell. Both ordinary Portland cement and conductive concrete were utilized for the target experiment. Elemental sulfur was observed in the coating sludge of conductive concrete, whereas this trend was not observed for ordinary Portland cement. These observations demonstrate that conductive concrete provides an electron pathway from deposited sludge in the bottom of sewer pipes to oxygen dissolved in surface water electrons generated from hydrogen sulfide oxidation in an anaerobic environment via conductive concrete. Finally, regarding the mechanism responsible for hydrogen sulfide oxidation, chemical oxidation was the dominant process, and biological processes did not play a significant role.
S. Hirose, Yugo Nishio, Trang Nakamoto et al.
Resourceedings · 2023
Various issues, such as population growth, agriculture, and urban expansion, have led to the continuous degradation of water resources. To solve this problem, sustainable water treatment technologies are required. In water treatment, microbial fuel cells (MFCs) have attracted attention because of their low cost and low risk of cross-contamination. However, the performance of the MFC degrades because of microbial adhesion to the cathode. In this research, we proposed using a blend of polytetrafluoroethylene (PTFE) and Japanese Sumi ink to prevent the adhesion of microbial cells to the cathode. The hydrophobic properties of PTFE prevented the adhesion of microbes on the cathode surface. In addition, the Sumi ink improved the electrical conductivity and physical stability of the cathode. It was confirmed that the hydrophobic properties of PTFE and the conductive and physical stability of Sumi ink could be fully exploited by adjusting the composition ratio of PTFE and Sumi ink.
Zeynal Topalcengiz, L. Strawn, M. Danyluk
PLOS ONE · 2017
The microbial quality of water that comes into the edible portion of produce is believed to directly relate to the safety of produce, and metrics describing indicator organisms are commonly used to ensure safety. The US FDA Produce Safety Rule (PSR) sets very specific microbiological water quality metrics for agricultural water that contacts the harvestable portion of produce. Validation of these metrics for agricultural water is essential for produce safety. Water samples (500 mL) from six agricultural ponds were collected during the 2012/2013 and 2013/2014 growing seasons (46 and 44 samples respectively, 540 from all ponds). Microbial indicator populations (total coliforms, generic Escherichia coli, and enterococci) were enumerated, environmental variables (temperature, pH, conductivity, redox potential, and turbidity) measured, and pathogen presence evaluated by PCR. Salmonella isolates were serotyped and analyzed by pulsed-field gel electrophoresis. Following rain events, coliforms increased up to 4.2 log MPN/100 mL. Populations of coliforms and enterococci ranged from 2 to 8 and 1 to 5 log MPN/100 mL, respectively. Microbial indicators did not correlate with environmental variables, except pH (P<0.0001). The invA gene (Salmonella) was detected in 26/540 (4.8%) samples, in all ponds and growing seasons, and 14 serotypes detected. Six STEC genes were detected in samples: hly (83.3%), fliC (51.8%), eaeA (17.4%), rfbE (17.4%), stx-I (32.6%), stx-II (9.4%). While all ponds met the PSR requirements, at least one virulence gene from Salmonella (invA-4.8%) or STEC (stx-I-32.6%, stx-II-9.4%) was detected in each pond. Water quality for tested agricultural ponds, below recommended standards, did not guarantee the absence of pathogens. Investigating the relationships among physicochemical attributes, environmental factors, indicator microorganisms, and pathogen presence allows researchers to have a greater understanding of contamination risks from agricultural surface waters in the field.
T. Ahmed, M. Noman, Yetong Qi et al.
Plants · 2023
Microbial compost plays a crucial role in improving soil health, soil fertility, and plant biomass. These biofertilizers, based on microorganisms, offer numerous benefits such as enhanced nutrient acquisition (N, P, and K), production of hydrogen cyanide (HCN), and control of pathogens through induced systematic resistance. Additionally, they promote the production of phytohormones, siderophore, vitamins, protective enzymes, and antibiotics, further contributing to soil sustainability and optimal agricultural productivity. The escalating generation of organic waste from farm operations poses significant threats to the environment and soil fertility. Simultaneously, the excessive utilization of chemical fertilizers to achieve high crop yields results in detrimental impacts on soil structure and fertility. To address these challenges, a sustainable agriculture system that ensures enhanced soil fertility and minimal ecological impact is imperative. Microbial composts, developed by incorporating characterized plant-growth-promoting bacteria or fungal strains into compost derived from agricultural waste, offer a promising solution. These biofertilizers, with selected microbial strains capable of thriving in compost, offer an eco-friendly, cost-effective, and sustainable alternative for agricultural practices. In this review article, we explore the potential of microbial composts as a viable strategy for improving plant growth and environmental safety. By harnessing the benefits of microorganisms in compost, we can pave the way for sustainable agriculture and foster a healthier relationship between soil, plants, and the environment.
Meitong Jiang, M. Delgado‐Baquerizo, M. Yuan et al.
New Phytologist · 2023
Soil microbial inoculants are expected to boost crop productivity under climate change and soil degradation. However, the efficiency of native vs commercialized microbial inoculants in soils with different fertility and impacts on resident microbial communities remain unclear. We investigated the differential plant growth responses to native synthetic microbial community (SynCom) and commercial plant growth-promoting rhizobacteria (PGPR). We quantified the microbial colonization and dynamic of niche structure to emphasize the home-field advantages for native microbial inoculants. A native SynCom of 21 bacterial strains, originating from three typical agricultural soils, conferred a special advantage in promoting maize growth under low-fertility conditions. The root : shoot ratio of fresh weight increased by 78-121% with SynCom but only 23-86% with PGPRs. This phenotype correlated with the potential robust colonization of SynCom and positive interactions with the resident community. Niche breadth analysis revealed that SynCom inoculation induced a neutral disturbance to the niche structure. However, even PGPRs failed to colonize the natural soil, they decreased niche breadth and increased niche overlap by 59.2-62.4%, exacerbating competition. These results suggest that the home-field advantage of native microbes may serve as a basis for engineering crop microbiomes to support food production in widely distributed poor soils.
Cheng Gao, Ling Xu, Liliam Montoya et al.
Nature Communications · 2022
Plant response to drought stress involves fungi and bacteria that live on and in plants and in the rhizosphere, yet the stability of these myco- and micro-biomes remains poorly understood. We investigate the resistance and resilience of fungi and bacteria to drought in an agricultural system using both community composition and microbial associations. Here we show that tests of the fundamental hypotheses that fungi, as compared to bacteria, are (i) more resistant to drought stress but (ii) less resilient when rewetting relieves the stress, found robust support at the level of community composition. Results were more complex using all-correlations and co-occurrence networks. In general, drought disrupts microbial networks based on significant positive correlations among bacteria, among fungi, and between bacteria and fungi. Surprisingly, co-occurrence networks among functional guilds of rhizosphere fungi and leaf bacteria were strengthened by drought, and the same was seen for networks involving arbuscular mycorrhizal fungi in the rhizosphere. We also found support for the stress gradient hypothesis because drought increased the relative frequency of positive correlations. Fungi are expected to be more resistant and less resilient than bacteria to environmental disturbances. Here, the authors report complex responses by microbial co-occurrence networks to drought in an agricultural system, challenging simple predictions of fungal and bacterial drought responses.
Jennifer E. Schmidt, R. Vannette, Alexandria N. Igwe et al.
Applied and Environmental Microbiology · 2019
Agriculture relies, in part, on close linkages between plants and the microorganisms that live in association with plant roots. These rhizosphere bacteria and fungi are distinct from microbial communities found in the rest of the soil and are even more important to plant nutrient uptake and health. Evidence from field studies shows that agricultural management practices such as fertilization and tillage shape microbial communities in bulk soil, but little is known about how these practices affect the rhizosphere. We investigated how agricultural management affects plant-soil-microbe interactions by comparing soil physical and chemical properties, plant nutrients, and rhizosphere microbial communities from paired fields under organic and conventional management. Our results show that human management effects extend even to microorganisms living in close association with plant roots and highlight the importance of these bacteria and fungi to crop nutrition and productivity. ABSTRACT Agricultural management practices affect bulk soil microbial communities and the functions they carry out, but it remains unclear how these effects extend to the rhizosphere in different agroecosystem contexts. Given close linkages between rhizosphere processes and plant nutrition and productivity, understanding how management practices impact this critical zone is of great importance to optimize plant-soil interactions for agricultural sustainability. A comparison of six paired conventional-organic processing tomato farms was conducted to investigate relationships between management, soil physicochemical parameters, and rhizosphere microbial community composition and functions. Organically managed fields were higher in soil total N and NO3-N, total and labile C, plant Ca, S, and Cu, and other essential nutrients, while soil pH was higher in conventionally managed fields. Differential abundance, indicator species, and random forest analyses of rhizosphere communities revealed compositional differences between organic and conventional systems and identified management-specific microbial taxa. Phylogeny-based trait prediction showed that these differences translated into more abundant pathogenesis-related gene functions in conventional systems. Structural equation modeling revealed a greater effect of soil biological communities than physicochemical parameters on plant outcomes. These results highlight the importance of rhizosphere-specific studies, as plant selection likely interacts with management in regulating microbial communities and functions that impact agricultural productivity. IMPORTANCE Agriculture relies, in part, on close linkages between plants and the microorganisms that live in association with plant roots. These rhizosphere bacteria and fungi are distinct from microbial communities found in the rest of the soil and are even more important to plant nutrient uptake and health. Evidence from field studies shows that agricultural management practices such as fertilization and tillage shape microbial communities in bulk soil, but little is known about how these practices affect the rhizosphere. We investigated how agricultural management affects plant-soil-microbe interactions by comparing soil physical and chemical properties, plant nutrients, and rhizosphere microbial communities from paired fields under organic and conventional management. Our results show that human management effects extend even to microorganisms living in close association with plant roots and highlight the importance of these bacteria and fungi to crop nutrition and productivity.
Vanessa L. Brisson, Jennifer E. Schmidt, T. Northen et al.
Scientific Reports · 2019
Maize domestication and breeding have resulted in drastic and well documented changes in aboveground traits, but belowground effects on root system functioning and rhizosphere microbial communities remain poorly understood, despite their critical importance for nutrient and water acquisition. We investigated the rhizosphere microbial community composition and structure of ten Zea mays accessions along an evolutionary transect (two teosinte, three inbred maize lines, and five modern maize hybrids) grown in nutrient depleted soil from a low input agricultural system. Microbial community analysis revealed significant differences in community composition between soil compartments (proximal vs. distal rhizosphere) and between plant genetic groups (teosinte, inbred, and modern hybrid). Only a small portion of the microbial community was differentially selected across plant genetic groups: 3.7% of prokaryotic community members and 4.9% of fungal community members were significantly associated with a specific plant genetic group. Indicator species analysis showed the greatest differentiation between modern hybrids and the other two plant genetic groups. Co-occurrence network analysis revealed that microbial co-occurrence patterns of the inbred maize lines’ rhizosphere were significantly more similar to those of the teosintes than to the modern hybrids. Our results suggest that advances in hybrid development significantly impacted rhizosphere microbial communities and network assembly.
R. Schmidt, Kelly Gravuer, A. V. Bossange et al.
PLOS ONE · 2018
Reducing tillage and growing cover crops, widely recommended practices for boosting soil health, have major impacts on soil communities. Surprisingly little is known about their impacts on soil microbial functional diversity, and especially so in irrigated Mediterranean ecosystems. In long-term experimental plots at the West Side Research and Extension Center in California’s Central Valley, we characterized soil microbial communities in the presence or absence of physical disturbance due to tillage, in the presence or absence of cover crops, and at three depths: 0–5, 5–15 and 15–30 cm. This characterization included qPCR for bacterial and archaeal abundances, DNA sequencing of the 16S rRNA gene, and phylogenetic estimation of two ecologically important microbial traits (rRNA gene copy number and genome size). Total (bacterial + archaeal) diversity was higher in no-till than standard till; diversity increased with depth in no-till but decreased with depth in standard till. Total bacterial numbers were higher in cover cropped plots at all depths, while no-till treatments showed higher numbers in 0–5 cm but lower numbers at lower depths compared to standard tillage. Trait estimates suggested that different farming practices and depths favored distinctly different microbial life strategies. Tillage in the absence of cover crops shifted microbial communities towards fast growing competitors, while no-till shifted them toward slow growing stress tolerators. Across all treatment combinations, increasing depth resulted in a shift towards stress tolerators. Cover crops shifted the communities towards ruderals–organisms with wider metabolic capacities and moderate rates of growth. Overall, our results are consistent with decreasing nutrient availability with soil depth and under no-till treatments, bursts of nutrient availability and niche homogenization under standard tillage, and increases in C supply and variety provided by cover crops. Understanding how agricultural practices shift microbial abundance, diversity and life strategies, such as presented here, can assist with designing farming systems that can support high yields, while enhancing C sequestration and increasing resilience to climate change.
Chao Zhang, Daoji Wu, Huixue Ren
Scientific Reports · 2020
Agricultural wastes, such as wheat bran and swine wastewater, were used for bioremediation of oil-contaminated soil. Two optimised strains that could degrade oil efficiently were selected. The result showed that the best ratio of strain A to strain B was 7:3. Swine wastewater could be a replacement for nitrogen source and process water for bioremediation. Next, the Box-Behnken design was used to optimise the culture medium, and the optimal medium was as follows: microbial dosage of 97 mL/kg, wheat bran of 158 g/kg and swine wastewater of 232 mL/kg. Under the optimal medium, the oil degradation rate reached 68.27 ± 0.71% after 40 d. The urease, catalase, and dehydrogenase activities in oil-contaminated soil all increased, and the microbe quantity increased significantly with manual composting. These investigations might lay a foundation for reducing the pollution of agricultural wastes, exploring a late model for bioremediation of oil-contaminated soil.
Jennifer E. Schmidt, A. Kent, Vanessa L. Brisson et al.
Microbiome · 2019
Rhizosphere microbial communities are key regulators of plant performance, yet few studies have assessed the impact of different management approaches on the rhizosphere microbiomes of major crops. Rhizosphere microbial communities are shaped by interactions between agricultural management and host selection processes, but studies often consider these factors individually rather than in combination. We tested the impacts of management (M) and rhizosphere effects (R) on microbial community structure and co-occurrence networks of maize roots collected from long-term conventionally and organically managed maize-tomato agroecosystems. We also explored the interaction between these factors (M × R) and how it impacts rhizosphere microbial diversity and composition, differential abundance, indicator taxa, co-occurrence network structure, and microbial nitrogen-cycling processes. Host selection processes moderate the influence of agricultural management on rhizosphere microbial communities, although bacteria and fungi respond differently to plant selection and agricultural management. We found that plants recruit management-system-specific taxa and shift N-cycling pathways in the rhizosphere, distinguishing this soil compartment from bulk soil. Rhizosphere microbiomes from conventional and organic systems were more similar in diversity and network structure than communities from their respective bulk soils, and community composition was affected by both M and R effects. In contrast, fungal community composition was affected only by management, and network structure only by plant selection. Quantification of six nitrogen-cycling genes (nifH, amoA [bacterial and archaeal], nirK, nrfA, and nosZ) revealed that only nosZ abundance was affected by management and was higher in the organic system. Plant selection interacts with conventional and organic management practices to shape rhizosphere microbial community composition, co-occurrence patterns, and at least one nitrogen-cycling process. Reframing research priorities to better understand adaptive plant-microbe feedbacks and include roots as a significant moderating influence of management outcomes could help guide plant-oriented strategies to improve productivity and agroecosystem sustainability.
Ziheng Peng, Xun Qian, Yu Liu et al.
Nature Communications · 2024
Agriculture contributes to a decline in local species diversity and to above- and below-ground biotic homogenization. Here, we conduct a continental survey using 1185 soil samples and compare microbial communities from natural ecosystems (forest, grassland, and wetland) with converted agricultural land. We combine our continental survey results with a global meta-analysis of available sequencing data that cover more than 2400 samples across six continents. Our combined results demonstrate that land conversion to agricultural land results in taxonomic and functional homogenization of soil bacteria, mainly driven by the increase in the geographic ranges of taxa in croplands. We find that 20% of phylotypes are decreased and 23% are increased by land conversion, with croplands enriched in Chloroflexi, Gemmatimonadota, Planctomycetota, Myxcoccota and Latescibacterota. Although there is no significant difference in functional composition between natural ecosystems and agricultural land, functional genes involved in nitrogen fixation, phosphorus mineralization and transportation are depleted in cropland. Our results provide a global insight into the consequences of land-use change on soil microbial taxonomic and functional diversity.
Samir K. Banerjee, Florian Walder, L. Büchi et al.
The ISME Journal · 2018
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.
O. Fasusi, C. Cruz, O. Babalola
Agriculture · 2021
The world’s human population continues to increase, posing a significant challenge in ensuring food security, as soil nutrients and fertility are limited and decreasing with time. Thus, there is a need to increase agricultural productivity to meet the food demands of the growing population. A high level of dependence on chemical fertilizers as a means of increasing food production has damaged the ecological balance and human health and is becoming too expensive for many farmers to afford. The exploitation of beneficial soil microorganisms as a substitute for chemical fertilizers in the production of food is one potential solution to this conundrum. Microorganisms, such as plant growth-promoting rhizobacteria and mycorrhizal fungi, have demonstrated their ability in the formulation of biofertilizers in the agricultural sector, providing plants with nutrients required to enhance their growth, increase yield, manage abiotic and biotic stress, and prevent phytopathogens attack. Recently, beneficial soil microbes have been reported to produce some volatile organic compounds, which are beneficial to plants, and the amendment of these microbes with locally available organic materials and nanoparticles is currently used to formulate biofertilizers to increase plant productivity. This review focuses on the important role performed by beneficial soil microorganisms as a cost-effective, nontoxic, and eco-friendly approach in the management of the rhizosphere to promote plant growth and yield.
Qianying Zhang, Tianfei Zheng, Zhenggang Yang et al.
Frontiers in Microbiology · 2023
The agricultural fermentation processing of cigar tobacco leaves (CTLs), including air-curing and agricultural fermentation, carried out by tobacco farmers has rarely been studied. In this study, we have investigated the microbial community in the CTLs during air-curing and agricultural fermentation by 16S rRNA and ITS gene high-throughput sequencing. The results showed that the richness of microbial communities gradually increased with the development of agricultural fermentation, which means that not all microorganisms in CTLs come from the fields where tobacco grows, but gradually accumulate into CTLs during the fermentation process. Enterobacteriaceae, Chloroplast, and Alternaria were the dominant genera in the air-cured CTLs. Aquabacterium, unclassified Burkholderiaceae, Caulobacter, Brevundimonas, and Aspergillus were the dominant genera in the agriculturally fermented CTLs. Acinetobacter, Methylobacterium, Sampaiozyma, and Plectosphaerella first significantly increased, and then significantly decreased during agricultural processing. The changes in microbial communities are mainly related to their different functions during fermentation. This means that when the fermentation effect of the original microbial community in cigar tobacco leaves is not ideal, we can optimize or design the microbial community based on the fermentation function that the microbial community needs to achieve. These results may help adjust and optimize the agricultural fermentation process of CTLs, and help develop the quality of CTLs and increase the income of tobacco farmers.
Yang Zhou, Ming-Rong Deng, Juan Du et al.
Chinese Journal of Engineering Science · 2022
: Agricultural microbial industry belongs to a biotechnology industry with high value addition. It utilizes agricultural microbial resources and biotechnologies, involves fields such as planting, breeding, and agricultural environment, and is crucial in ensuring food security, improving cultivated land quality, and promoting agricultural emission reduction. In this study, we reviewed the development status of agricultural microbial industry in China from the aspects of microbial fertilizer, microbial feeds, microbial pesticide, and microbial enzyme preparation. Then we summarized the development trends of the agricultural microbial technology and industry. Considering the challenges faced by the industry in terms of germplasm resources, technical research, product development, and industry standards, we proposed several key measures including establishing special projects for scientific research platforms, building data information systems, strengthening innovation in the microbial seed industry, and building systems of laws and regulations. To contribute to the high-quality development of China’s agricultural microbial industry, we suggest that an industrial policy system and related supporting measures should be established, the innovation system for the industry should be improved, and high-tech enterprises participating in international competition should be built.
Mihret Frew, Kiros Abebe
Agricultural Reviews · 2020
Milk and milk products play a vital role in human nutrition all over the world. In addition to being a nutritious food for humans, milk and milk products provide a favorable environment for the growth of spoilage and pathogenic microorganisms. Thus, this paper aims to review the microbial properties of milk and fermented milk products produced in different parts of Ethiopia. Microbial contamination may generally occur from within the udder, exterior to the udder, from the surface of milk handling and storage equipment and the traditional practice. The status of the cleanliness of the milkers could be the primary sources of the initial milk contamination. The reviewed dairy products are Milk, Ergo (naturally fermented milk), Kibe (traditional butter), Arera (defatted sour milk) and Ayib (Ethiopian cottage cheese). The existing microbial quality of dairy products produced in the rural part of Ethiopia was poor and did not meet the acceptable quality requirements. The problem was compounded from limited knowledge of the hygienic production, processing and handling of dairy products coupled with inadequate dairy processing infrastructures. Strict hygienic control measures along the value chain to improve the hygienic conditions of milk starting from production to consumption are necessary to provide safe products to the consumer.
PRANITA JAISWAL, YUDH VIR SINGH, NEHA SHARMA et al.
The Indian Journal of Agricultural Sciences · 2020
A field experiment was conducted to study the comparative influence of microbial preparations ,viz. phosphate solubilizing fungi (Jumpstart 2.0), phosphate solubilizing bacteria (PSB), Arbuscular mycorrhiza fungi and humic acid formulation (Bolt GR), in different combinations on soil microbial population and properties (Alkaline phosphatase, dehydrogenase, FDA hydrolytic activity, soil microbial biomass). Bacteria dominated the microbial population, with initial cfu level of 1.73 × 107 to a maximum of 6.2 × 107 gm-1 soil on 90 days after sowing (DAS) in plot, where PSB was applied @ 500 g/ ha, while plots with Jumpstart 2.0 application (@1.65 ml/ kg seed) recorded higher fungal population (7.4 × 106 cfu/g). Treatments and crop age had significant impact on microbial population and their interaction was also found to be significant. Soil microbial properties also increased significantly with crop aging and reached to a higher level on 90 DAS for all the treatments. Microbial activity was invariably found to be highest in T7 treatment (application of PSF @ 0.83 ml/kg seed with humic acid @ 10 kg/ha), and lowest in control plots irrespective of sampling intervals. Results concluded that application of PSF, PSB, AM Fungi and organic formulations in different combination had favourably influenced the microbial properties of soil.
Tim Dumonceaux
Microorganisms · 2023
Peter Kropotkin (1842–1921) is well known as an anarchist intellectual, an amiable mass of contradictions who loved humanity and was highly regarded in academic and intellectual circles, yet also penned “fiery peans to violence” in Le Révolté, the anarchist journal he established with Elisée Reclus in the 1870s [...]
Sivakumar K, Babu R, Venkataraman N.S et al.
Madras Agricultural Journal · 2021
Field investigations were conducted to assess the effect of conservation agricultural practices on soil biological properties and yield of cotton during the kharif season of 2018 and 2019. The experiments were laid out in a split plot design with four main factors viz., conventional tillage with irrigation schedule of 0.8 IW/CPE ratio (M1), conventional tillage with irrigation schedule of 0.6 IW/CPE ratio (M2), minimum tillage with irrigation schedule of 0.8 IW/CPE ratio (M3) and minimum tillage with irrigation schedule of 0.6 IW/CPE ratio (M4). Sub plot had six treatments of weed and nutrient management viz., crop residue mulch with 100% RDF (S1), crop residue mulch with 75% RDF (S2), pre-emergence application of pendimethalin fb one hand weeding with 100% RDF (S3), pre-emergence application of pendimethalin fb one hand weeding with 75% RDF (S4), mechanical weeding twice with 100% RDF (S5) and mechanical weeding twice with 75% RDF (S6). Total microbial populations viz., bacteria, fungal, and actinobacteria were higher in cotton rhizosphere soil with the minimum tillage of irrigation at 0.8 IW/CPE ratio (M3) in the main plot treatments. Cotton rhizosphere soil with crop residue mulch with 100% RDF (S1) recorded a higher microbial population and it was statistically similar with pre-emergence application of pendimethalin fb one hand weeding with 100% RDF (S3) in the sub plot treatments. Among the treatment combination, minimum tillage with irrigation at 0.8 IW/CPE ratio (M3) and crop residue mulch with 100% RDF (S1) recorded a higher microbial population. Similarly, a higher seed yield of cotton was also recorded with minimum tillage and irrigating the crop at 0.8 IW/CPE ratio and pre-emergence application of pendimethalin fb one hand weeding along with application of 100% RDF (M3S3)
Ali YETGİN
Journal of Agricultural Production · 2023
The world is facing a hidden hunger crisis, where millions of people are suffering from nutritional deficiencies despite having access to food. While much research has focused on the quality and quantity of food, recent studies have shown that soil microbial diversity may also play a crucial role in human nutrition. Soil microbes interact with plants in complex ways, influencing the absorption of nutrients and producing compounds that are essential for human health. However, factors such as intensive agriculture, climate change, and soil pollution can lead to a decline in soil microbial diversity, which may contribute to the rise of hidden hunger. In this paper, we explore the link between soil microbial diversity and nutritional deficiencies, examining the latest research on the topic and discussing potential solutions to this pressing global issue. Our findings suggest that promoting soil health and biodiversity could be a key strategy for addressing hidden hunger and improving global nutrition.
A. S. Wieczorek, S. A. Hetz, S. Kolb
· 2014
Abstract. Chitin is the second most abundant biopolymer in terrestrial ecosystems and is subject to microbial degradation. Chitin can be deacetylated to chitosan or can be hydrolyzed to N,N′-diacetylchitobiose and oligomers of N-acetylglucosamine by aerobic and anaerobic microorganisms. Which pathway of chitin hydrolysis is preferred by soil microbial communities has previously been unknown. Supplementation of chitin stimulated microbial activity under oxic and anoxic conditions in agricultural soil slurries, whereas chitosan had no effect. Thus, the soil microbial community likely was more adapted to chitin as a substrate. In addition, this finding suggested that direct hydrolysis of chitin was preferred to the pathway that starts with deacetylation. Chitin was apparently degraded by aerobic respiration, ammonification, and nitrification to carbon dioxide and nitrate under oxic conditions. When oxygen was absent, fermentation products (acetate, butyrate, propionate, hydrogen, carbon dioxide) and ammonia were detected, suggesting that butyric and propionic acid fermentation were along with ammonification likely responsible for apparent anaerobic chitin degradation. In total, 42 different chiA genotypes were detected of which twenty were novel at an amino acid sequence dissimilarity of >50%. Various chiA genotypes responded to chitin supplementation and affiliated with a novel deep-branching bacterial chiA genotype (anoxic conditions), genotypes of Beta- and Gammaproteobacteria (oxic and anoxic conditions), and Planctomycetes (oxic conditions). Thus, this study provides evidence that detected chitinolytic bacteria were catabolically diverse and occupied different ecological niches with regard to oxygen availability enabling chitin degradation under various redox conditions at the level of the community.
Jon Cotton, Veronica Acosta‐Martínez
Agricultural & Environmental Letters · 2018
Core Ideas Decreased CRP funding is resulting in US grassland being tilled. Intensive tillage of grassland rapidly decreases soil health indicators. One month after tilling grassland surface microbial biomass (0–10 cm) decreased 52%. Soil organic C decreased by 20% in the top 30 cm after one growing season. Alternative grassland conversion methods are needed to sustain soil health. Intensive tillage of grassland has negative long‐term effects on soil health, but little data exist to understand how quickly this decline occurs. We sampled a commercial field in the semiarid Southern Plains of the United States before and after tilling grassland and compared the results to adjacent row crop and perennial grass fields. Within the first month of tillage, we detected losses of 52% of microbial biomass C (505 to 241 mg kg −1 soil), 33% of organic C (11.6 to 7.78 g kg −1 soil), 30% of total N (1.09 to 0.760 g kg −1 soil) and 64 to 70% of β‐glucosidase and phosphodiesterase activities. The rapid decreases in these soil health indicators demonstrate that tillage management decisions are crucial for maintaining soil health if perennial grasses are converted to row cropping.
Olivia McKay, Grace Pold, Philip Martin et al.
Frontiers in Environmental Science · 2022
Agricultural plastics support crop production and quality by reducing weeds, improving irrigation efficiency, and regulating soil conditions, but can also become a soil pollutant. While microplastic effects on soil function are increasingly well-understood, the impacts of agricultural macroplastic (&gt;5 mm) contamination on soils are poorly documented. Prolonged exposure to plastic macrofragments may alter microbial decomposer community structure and function, since plastic can directly affect edaphic factors while leaching novel compounds. To better characterize how plastic contamination influences the soil habitat, we sampled three farms characterized by agricultural plastic pollution in Monterey County, CA, United States. Using a randomized block design, we collected surface soil samples from the fields (“bulk PC soil”) to compare with soil directly in contact with the remaining polyethylene (PE) mulch and polyvinyl chloride (PVC) dripline fragments (“plastic-associated soil”). Soil directly associated with plastic fragments was hypothesized to have reduced microbial biomass and decomposer activities relative to the bulk soil, due to a greater likelihood of toxicity. In contrast to our expectations, we found that both PE and PVC macrofragments support a distinct microbial habitat that hosts a larger, more efficient microbial biomass with greater labile nutrient pools than the surrounding bulk soil. Because of the scope of macroplastic pollution likely occurring in agricultural soils, our findings suggest that this novel plastisphere habitat may significantly alter ecological functions critical to agricultural soils over time by encouraging microbial colonization within plastic debris.
Jeya Bharathi M, Balachandar D, Narayanan R et al.
Madras Agricultural Journal · 2011
Precision farming is an integrated plant nutrient management system attempt to deliver the inputs actual crop needs without disturbing the entire farming area. The fertilizers in liquid state will be delivered through laterals directly to the root zone at high concentrations. Soil microorganisms are potential resources for soil productivity and sustainability, intended to be influenced by various anthropogenic-and farming activities. Hence in present study, we have investigated that the effect of different dose of liquid fertilizers on changes in soil microbial populations and enzyme activities of maize in comparison with conventional practice of fertilization. The results clearly revealed that all the fertilization reduced the microbial population and enzyme activities of maize rhizosphere and among the fertigations, 75 per cent of recommended NPK in the form of liquid fertilizer had a less reduction in the population of Azospirillum, P solubilising bacteria and total diazotrophs, soil respiration and enzyme activities. Hence it is evident from the study that the use of more organic manures and microbial inoculants along with inorganic chemicals fertilizers, as integrated approach is needed for precision farming.
Thiruveni T, Shanthi M, Murali Baskaran R K et al.
Madras Agricultural Journal · 2012
A field experiment was conducted during Kharif 2009 to evaluate the microbial consortia mediated resistance against okra shoot and fruit borer, Earias vittella (Fab.) in okra variety, Arka Anamika and hybrid, CoBhH1. The microbial consortium Pseudomonas fluorescens Pf1 + Beauveria bassiana B2 isolate (Pf1 + B2) was effective in reducing the shoot and fruit borer infestation through seed treatment, soil application and foliar spray. Pf1 + B2 recorded minimum shoot damage during vegetative and reproductive phases (3.99 and 14.33 %) as against untreated check (13.58 and 24.16 %). Fruit infestation was less in Pf1 +B2 consortia treatments on weight and number basis (4.22 and 2.83%), whereas it was 13.59 and 17.96 per cent in untreated check. Phenol content was high in Pf1+B2 consortia treated plants in Arka Anamika (0.94 mg/g) and CoBhH1 (1.39 mg/g), as against untreated check (0.20 and 0.41 mg/g, respectively). There was significant negative correlation between the shoot and fruit borer infestation and phenols (r=-0.937**), defensive enzymes viz., peroxidase (r=-0.909*), poly phenol oxidase (r=-0.993**), and phenyl alanine ammonia lyase (r=-0.960**).
Youming Shen, Jiyun Nie, Lixue Kuang et al.
Microbial Biotechnology · 2021
Summary The development of DNA sequencing technology has provided an effective method for studying foodborne and phytopathogenic microorganisms on fruits and vegetables (F & V). DNA sequencing has successfully proceeded through three generations, including the tens of operating platforms. These advances have significantly promoted microbial whole‐genome sequencing (WGS) and DNA polymorphism research. Based on genomic and regional polymorphisms, genetic markers have been widely obtained. These molecular markers are used as targets for PCR or chip analyses to detect microbes at the genetic level. Furthermore, metagenomic analyses conducted by sequencing the hypervariable regions of ribosomal DNA (rDNA) have revealed comprehensive microbial communities in various studies on F & V. This review highlights the basic principles of three generations of DNA sequencing, and summarizes the WGS studies of and available DNA markers for major bacterial foodborne pathogens and phytopathogenic fungi found on F & V. In addition, rDNA sequencing‐based bacterial and fungal metagenomics are summarized under three topics. These findings deepen the understanding of DNA sequencing and its application in studies of foodborne and phytopathogenic microbes and shed light on strategies for the monitoring of F & V microbes and quality control.
Selvi D, Chitdeshwari T, Balachandar D
Madras Agricultural Journal · 2022
The studyaimed to evaluate the efficiencyof different sources of Zinc and organic manures with and without microbial inoculants on the bioavailability of Zinc in soil. Four different zinc sources namely ZnSO4, ZnPO4, ZnO, and Zn-EDTA, and two organic manures viz., farm yard manure (FYM) and Vermicompost (VC) were evaluated in the presence and absence of Zinc Solubilizing Bacteria (ZSB). Among the different combinations of the above factors, ZnSO4+FYM+ZSB combination recorded a maximum reduction in pH (6.82) whereas, ZnSO4+Vermicompost+ZSB recorded the highest Electrical Conductivity (EC) (0.4 dSm-1). Regarding DTPA-Zn availability Zn-EDTA recorded the highest concentration in soil both as a sole and combined application with organic and microbes. The dehydrogenase activity was upsurged in organic applied treatments and was less in fertilizer applied treatments. Zinc oxide recorded maximum dissolution efficiency compared to other sources of Zinc.
Rosa Boone, Bjorn Robroek, Wim van der Putten et al.
· 2025
Our current agricultural system is non-sustainable due to its negative impact on soil and water quality, and its eroding effect on biodiversity. To promote sustainability while maintaining productivity, we need to explore alternative practices. One such strategy is the extensification of agricultural management, which reduces external inputs while aiming to enhance soil functioning. Nutrient cycling, a key soil function, may improve under extensification due to shifts in abiotic conditions and microbial community interactions. However, the mechanisms by which extensification affects soil microbial communities and their functional interactions in field conditions remain poorly understood. In this study, we investigated how management extensification affects soil nutrient cycling. We assessed nutrient cycling using enzymatic assays, Microresp analysis, and Teabag decomposition, and evaluated the role of abiotic factors (e.g., pH, SOC) and microbial community composition along an agricultural extensification gradient, ranging from conventional productive grasslands to semi-natural grasslands. Microbial interactions were explored using co-occurrence network analysis to assess how management influences the community as a whole. Preliminary results show that fungal communities change with extensification, accompanied by an increase in overall soil nutrient functioning, particularly for decomposition rate. Our results highlight that management choices have implications for soil functioning, and that the validity to use soil parameters to underpin soil nutrient functioning are highly context dependent.
Armi Kaila
Agricultural and Food Science · 1951
An attempt has been made in the present investigation to elucidate the influence of growing legumes upon the microbial population and upon its activities in the soil. Annual legumes, pea and vetch were compared with oats, and red clover with timothy. At the beginning and at the end of the summer the number of bacteria, calculated through various culture media, appeared to be greater in the rhizosphere of the pea plants than under the vetch or oat plants. The rhizosphere flora of the young pea plants showed a capacity for more active nitrogen fixation than that of the young vetch or oat plants, but later the superiority of the pea plants disappeared. A higher rate of nitrification under and for some time after the legume crops compared with the corresponding non-legume crops was noted. Nitrification of added ammonium sulfate did not occur more actively under the legumes, due either to the lack of a stimulation of the nitrifying flora, or to the higher acidity in the legume soils. Compared with the non-legumes, the legumes could not be found to stimulate carbon dioxide production from the soil in any other way than through their more easily decomposable residues. Within the bounds of this investigation no special effect of legumes upon the soil flora could be established that cannot be explained on the basis of their nitrogen economy, either their utilizing soil nitrogen to a smaller degree than non-legumes, or due to composition of their roots and stubble. Under the field conditions, however, several other factors not demonstrable from this material may exist.
Yadollah. Ghafuri, Ahmad Reza. Yari, Saeed. Shams et al.
Research Square · 2022
Abstract Background This study was designed to investigate microbial exposure risk assessment and consequences of adverse health effects due to the use of irrigation of fields with wastewater in Qom province Methods Environmental monitoring program for 3 pathogens including Escherichia coli, Vibrio cholerae and Ecoli O157 in raw sewage and treated wastewater and irrigated products with wastewater, was performed. Results Results was shown that in the raw wastewater, concentrations of E.coli, Vibrio Cholerae and E.coli O157:H7, 3.4×103±500, 2.1×103±100 and 312 respectively were determined. Concentrations of E.coli, Vibrio Cholerae and E.coli O157:H7 in wastewater effluent 2.1×103±100, 0.8×103±100 and 176 respectively were determined. Based on these findings, it is determined that the conventional wastewater treatment system has been effective in removing E.coli, Vibrio Cholerae and E.coli O157: H7 by 50%, 59% and 43%, respectively. Irrigated crops with wastewater effluent containing 400±250, 0.1×103±0.019 and 52 for E.coli, Vibrio Cholerae and E.coli O157:H7 respectively were measured. In this study according to the exposure scenarios including accidental drinking, food crop consumption, dermal contact by wastewater effluent and dermal contact by raw wastewater, total annual Probability of infection in studied population for E.coli, Vibrio Cholerae and E.coli O157:H7, 8×10-2, 8×10-4 and 0.17 respectively was determined. Conclusions Implementing of wastewater safety plans (WWSP) to safeguard wastewater quality, raising awareness in the population in contact with urban wastewater and upgrading wastewater treatment plants is inevitable.
Hui Li, Shuwen Gu, Libao Wang et al.
Fishes · 2024
The aim of this study was to investigate the dynamic changes in the microbial communities of both the environment and gut of Litopenaeus vannamei, as well as to elucidate the mechanisms underlying microbial community assembly in greenhouse farming. 16S rDNA high-throughput sequencing and bioinformatics methods were used to carry out the research on the community structure of the microorganisms under greenhouse culture conditions in water, sediment, and gut microorganisms; correlations pertaining to environmental factors; the feasibility of using Source Tracker; and the mechanisms of community construction. The results show that the dominant microorganisms in water, sediment, and gut farming in a greenhouse environment varied and were subject to dynamic change. A variety of beneficial microbiota such as Bacillus were found in the gut, whereas a variety of microorganisms such as Marivita and Pseudomonas, which function as nitrogen and phosphorus removers, were present in water. Source Tracker and environmental correlation analyses showed that changes in the gut were associated with eutrophication indicators (total nitrogen, total phosphorus, ammonia nitrogen) and changes in environmental microorganisms (in water and sediment). The results of the community-building mechanism analysis show that stochastic processes determine the community-building directions of environmental and gut microorganisms. These findings will help us to understand the microbiota characteristics of shrimp ponds under greenhouse farming conditions, and the complex interactions between the shrimp gut and the environmental microbiota and environmental variables, as well as revealing the changing rules of the gut microbiota.
Vito Abbruzzese
· 2021
The data presented here are related to the research article entitled ‘Effects ofsubstrate quality on carbon partitioning and microbial community composition in soil from an agricultural grassland’ [1]. Data illustrate cumulative CO2 efflux, microbial biomass C (Cmic), priming effect expressed as priming index (PI) and total phospholipid fatty acid (PLFA) profiles. The data were measured during four soil laboratory incubations using a silty clay loam soil under permanent grassland from May until August 2015. The soil was treated with carbohydrates of different complexity (glucose, glucose-6-phosphate (G6P) or cellulose) alone or in conjunction with livestock slurry amended or non-amended with a biological additive. Our data may be of great significance for further studies on microbial respiration and biosynthesis, and microbial community structure following slurry application to soil, alongside the potential beneficial effects of the addition of slurry amended with biological additives.
Sudhamayee Behura
African Journal of Biological Sciences · 2024
Environmental pollution from agricultural activities poses significant challenges globally. Bioremediation, using microbial diversity to degrade contaminants, offers a sustainable solution. This study explores microbial diversity's potential in agricultural waste bioremediation. Agricultural wastes, including crop residues and agro-industrial by-products, contribute to soil degradation and water pollution
Zahra F. Islam, Chris Greening, Hang‐Wei Hu
Microbial Biotechnology · 2023
Abstract Hydrogen‐oxidising bacteria play a key role in maintaining the composition of gases within the atmosphere and are ubiquitous in agricultural soils. While studies have shown that hydrogen accumulates in soil surrounding legume nodules and the soil surface, soils as a whole act as a net sink for hydrogen, raising questions about how hydrogen is internally recycled by soils. Can the energy derived from hydrogen oxidation be directly funnelled into plants to promote their growth or does it only act as a booster for other plant‐growth promoting bacteria? Moreover, while the fertilisation effect of hydrogen on plants has previously been shown to be beneficial, questions remain about the upper limit of hydrogen uptake by plants before it becomes detrimental. Agricultural practices such as fertilisation may impact the balance of hydrogen‐oxidisers and hydrogen‐producers in these ecosystems, potentially having detrimental effects on not only agricultural land but also global biogeochemical cycles. In this perspectives piece, we highlight the importance of understanding the contribution of hydrogen to agricultural soils and the effects of agricultural practices on the ability for bacteria to cycle hydrogen in agricultural soils. We propose a framework to gain better insights into microbial hydrogen cycling within agroecosystems, which could contribute to the development of new agricultural biotechnologies.
Elena I. Gavrikova, Roman V. Shkrabak, Vladimir S. Shkrabak et al.
Bulletin Samara State Agricultural Academy · 2025
Food production carried out by workers in a number of sub-sectors of the agro-industrial complex is inextricably linked with their identification with the sources of microbial contamination. Largely, this applies to the types of activity carried out in stationary facilities of the industry year-round or seasonally in some types of work. This is evidenced by the information provided in the article on the annual commissioning of new stationary facilities in the country for year-round keeping of animals, poultry, storage and processing of products in order to resolve issues of food supply of the population and raw materials for industry. As a rule, these are objects with permanent sources of microbial contamination. Workers engaged in industries with increased microbial contamination are susceptible to pathological processes caused by the chronicity of the infectious process and a decrease in the body's immune resistance. Microorganisms and their waste products found in the working area of a number of livestock, poultry, plant growing, fruit and vegetable (including greenhouse) industries lead to an increased susceptibility to infections, diseases, and, consequently, to an increase in the periods of temporary disability. Designing technical means and compiling disinfectant compositions to correct the level of microbial contamination leads to a decrease in the overall incidence rate and periods of temporary disability of workers, which will increase labor productivity and reduce the labor intensity of obtaining products. In this regard, an original model system was proposed in which the antioxidant properties of essential oils were studied by reaction with thiobarbituric acid under different experimental conditions (with and without heating). As a result of the experiments, it was found that heated anise essential oil and Morrison mustard plaster essential oil have the greatest anti-free radical activity. Devices for introducing essential oils into the respiratory tract have been developed. A method of phytodisinfection is proposed for air treatment, as a result of which the total microbial contamination in the premises is reduced on average by 3 times, the content of mold fungi - by 4 times.
Katya Dimitrova
Agricultural Sciences · 2024
The establishment of eco-friendly principles in agriculture requires, from one side, a reduced dependence on chemical fertilizers, pesticides and herbicides, and on the other, a maintenance of consistent yield and high plant productivity. Such substantial shift in the contemporary agricultural practices can be achieved only if a wide variety of alternative options is available. Furthermore, in order to become part of agricultural practices these options have to be affordable in a broad scale and effective against the loss of biodiversity and reduced soil fertility. The current study presents data about the metabolic activity and microbial community` structure in two soil samples – one treated with chemical fertilizer and another treated with chemical fertilizer reduced by 25% dose and supplemented with commercially available biofertilizer. Metabolic activity and properties of microbial soil communities were assessed by the BIOLOG® EcoPlate technique. The estimated parameters included average well-color development (AWCD) and utilisation of six guilds of substrates. Several functional indexes that are used for evaluation of community diversity and evenness were also estimated. The AWCD, expressed either as total activity or as guilds utilisation during the EcoPlate incubation period of seven days did not reveal significant difference between variants. However, most of the estimated functional indexes consistently indicated higher microbial diversity and more balanced structure of microbial community in the biofertilizer-supplemented variant. The results clearly implied that the biofertilizer based on nitrogen-fixing bacteria can positively influence the structure of soil communities and its application could be beneficial for soil fertility and plant productivity. Keywords: diazotroph, biofertilizer, BIOLOG® EcoPlate, functional indexes, metabolic activity, microbial communities
Kalisa Bogati, Piotr Sewerniak, Maciej Walczak
bioRxiv (Cold Spring Harbor Laboratory) · 2024
Abstract In this study, the impact of a two-month of drought stress on the microbial abundance, their enzymes and functional diversity in four agricultural soil (Gniewkowo (G), Lulkowo (L), Nieszawa (N), and Suchatówka (S) sites from Poland) was investigated during summer season. The physicochemical parameters (pH, organic carbon (C), calcium carbonate (CaCO 3 ), total nitrogen (N), nitrate (NO 3 - ), ammonium (NH 4 + ), total phosphorus (P), available phosphate (P 2 O 5 )), and specific biological parameters (microbial abundance, CLPP, and soil enzymes (phosphatases (acid; ACP and alkaline; AKP), dehydrogenase (DH), and urease (UR)) were conducted on the soil samples in this study. The physicochemical and biological data were compared between zero-week (T0) and 8 th week (T8) time intervals. The microbial enumeration showed higher bacterial populations (496.63 x 10 4 CFU g -1 dry soil) compared to actinomycetes (13.43 x 10 4 CFU g −1 dry soil), and lowest were the fungal population (67.68 x 10 2 CFU g -1 dry soil) at T8. The functional diversity showed strong positive significance in the G, N and S sites at T8. On the contrary, most of the L sites showed negative significance with the utilization of amines only, by the end of the experiment. Overall, the microbial population, their enzymes and functional diversity showed positive correlation with soil moisture content in all four investigated sites. The findings of our study indicate that soil biological activities in agricultural regions can be modified by a mere two months of drought.
Giovana P. F. Macan, Manuel Anguita-Maeso, Blanca B. Landa
· 2023
Currently, plastic mulch debris represent one of the main sources of microplastic pollution in agricultural soils. However, there is still limited research on plastic and microorganisms' interaction in terrestrial agroecosystems as compared to marine ecosystems. In this study, we have characterized the microbial communities associated with agricultural plastic mulch debris by using culture-dependent, and culture-independent (i.e., high-throughput DNA sequencing) approaches. Weathered plastic mulch debris samples were collected from the topsoil of five agricultural fields in Baza, Granada province in southern Spain, characterized by intensive horticultural production over the last ten years. The bacterial communities from the plastisphere soil (soil tightly adhered to the plastic) as well as the community tightly attached to the plastic surface were assessed by estimating the culturable populations by dilution plating on general media and the total (culturable and non-culturable) populations by NGS analysis of 16S rRNA amplicons. Additionally, all the plastic samples were characterized by FTIR spectroscopy and identified as polyethylene. The results from the culturable approach showed a significantly higher number of colony-forming units in the plastisphere soil than on the plastic surface, revealing some differences among field plots. Furthermore, 16S rRNA amplicon sequencing showed that the bacterial alpha-diversity, as measured by Richness index was higher in the plastisphere soil. Beta diversity Weighted-UniFrac index indicated that the main significant differences in the bacterial communities occurred among field plots, which might be related to the soil type, and/or crop history, and a lower effect of the plastic niche sampled. Some genera such as Arthrobacter, Bacillus, Blastococcus, Kocuria, Nocardioides, Sphingomonas, and Streptomyces were present in high abundance on both plastisphere soil and plastic surface from all the assessed fields. Furthermore, in one of the fields, the genera Polycyclovorans and Bdellovibrio showed significantly higher abundance in the plastic surface than in the plastisphere soil, indicating in this case a selective effect of the plastic for specific bacterial genera. Further research is still needed to better understand the potential impacts of plastic pollution on terrestrial agroecosystems as well as the complex interaction between plastic and microorganisms.&#8220;This project has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under the Marie Sk&#322;odowska-Curie grant agreement No. 955334 - SOPLAS.&#8221;
Wagner Bettiol, Flávio Henrique Vasconcelos de Medeiros, Josiane Barros Chiaramonte et al.
Burleigh Dodds Series in Agricultural Science · 2021
The success of a biological control programme depends on the isolation and selection of antagonists. There is an enormous diversity of culturable microbial species in the soil, rhizosphere, phylloplane, spermosphere and carposphere, which can be used in the isolation and selection of antagonists. The structures of fungal plant pathogens concerned with survival and infection may also be sources of antagonists. Although non-culturable microorganisms and microbiome-based strategies have great potential for development as commercial products in disease control, more knowledge is needed to understand the mechanisms involved in interactions between plants and complex microbial communities. Methods of isolation and selection of the most commercially exploited groups of antagonists and their advantages and disadvantages are discussed in this chapter as well as those of non-traditional antagonists. Finally, possible strategies for engineering the soil and host microbiome to actively promote plant protection against pathogens are discussed.