[Effects of Organic Fertilization on Bacterial Community and Maize Productivity in Dryland Red Soil].

Since 2002, a long-term field experiment has been conducted to determine the effects of different organic fertilization treatments on the bacterial community characteristics and maize productivity in dryland red soil using high-throughput sequencing technology. The experiment consisted of four treatments:no manure, M0; low manure, M1; high manure, M2; and high manure with lime addition, M3. Our results showed that the different organic fertilization treatments(M1, M2, and M3) significantly promoted maize productivity with the highest values of pH, soil organic matter(SOM), total nitrogen(TN), and total phosphorus(TP) compared to that under the M0 treatment, and the high manure with lime addition(M3) treatment had the highest level of maize production.

Cadmium tolerance in Elodea canadensis Michx: Subcellular distribution and metabolomic analysis.

The aquatic plant Elodea canadensis is considered a good candidate for ecotoxicological investigations. Cadmium (Cd) is a widespread contaminant in aquatic systems. In this study, to better elucidate the underlying tolerance mechanism and molecular impact of environmentally relevant Cd concentration in aquatic plants, subcellular distribution, chemical forms, and gas chromatography-mass spectrometry-based non-targeted metabolomics profiles were comprehensively analyzed in E.

Integrating pH into the metabolic theory of ecology to predict bacterial diversity in soil.

Microorganisms play essential roles in soil ecosystem functioning and maintenance, but methods are currently lacking for quantitative assessments of the mechanisms underlying microbial diversity patterns observed across disparate systems and scales. Here we established a quantitative model to incorporate pH into metabolic theory to capture and explain some of the unexplained variation in the relationship between temperature and soil bacterial diversity. We then tested and validated our newly developed models across multiple scales of ecological organization.

Dynamic Responses of Ammonia-Oxidizing Archaea and Bacteria Populations to Organic Material Amendments Affect Soil Nitrification and Nitrogen Use Efficiency.

Organic material amendments have been proposed as an effective strategy to promote soil health by enhancing soil fertility and promoting nitrogen (N) cycling and N use efficiency (NUE). Thus, it is important to investigate the extent to which the structure and function of ammonia-oxidizing archaea (AOA) and bacteria (AOB) differentially respond to the organic material amendments in field settings. Here, we conducted a 9-year field experiment to track the responses of AOA and AOB populations to the organic material amendments and measured the potential nitrification activity (PNA), plant productivity, and NUE in the plant rhizosphere interface.

Organism body size structures the soil microbial and nematode community assembly at a continental and global scale.

Body size is a key life-history trait that influences community assembly by affecting how ecological processes operate at the organism level. However, the extent to which the relative influences of ecological processes mediate the assembly of differentially sized soil organisms is still unknown. Here, we investigate the community assembly of differentially sized soil microorganisms and microfauna using a continental-scale sampling effort combined with a global-scale meta-analysis.

Trophic interactions as determinants of the arbuscular mycorrhizal fungal community with cascading plant-promoting consequences.

Background: The soil mycobiome is composed of a complex and diverse fungal community, which includes functionally diverse species ranging from plant pathogens to mutualists. Among the latter are arbuscular mycorrhizal fungi (AMF) that provide phosphorous (P) to plants. While plant hosts and abiotic parameters are known to structure AMF communities, it remains largely unknown how higher trophic level organisms, including protists and nematodes, affect AMF abundance and community composition.

Coupling Bacterial Community Assembly to Microbial Metabolism across Soil Profiles.

Soil microbial community assembly is crucial for understanding the mechanisms of microbial communities that regulate ecosystem-level functioning. The relative contributions of stochastic and deterministic processes to microbial community assembly remain poorly defined, and major questions exist concerning the soil organic carbon (SOC) dynamics of microbial community assembly in deep soil. Here, the bacterial community assembly processes were explored across five soil profile depths (up to 80 cm) during a 15-year field experiment involving four fertilization regimes.

Metabolic modifications to Ni excess in L. minor: Role of organic-, amino- and fatty acid profiles.

In this study, the effects of excess nickel (Ni) (100 μM and 200 μM) on growth, antioxidant production, fatty acid, organic and amino acids profiles were examined in Lemna minor L. After 7 days of Ni treatment, chlorosis, growth inhibition and ROS overproduction were observed, accompanied by Ni accumulation. Interestingly, decreased malondialdehyde (MDA) levels were recorded in fronds upon Ni exposure.

Correction to: Competitive interaction with keystone taxa induced negative priming under biochar amendments.

Following publication of the original article [1], the authors reported an error in the Additional file 1.

Toxic effects of Pb on Spirodela polyrhiza (L.): Subcellular distribution, chemical forms, morphological and physiological disorders.

The impact of lead (Pb) on Spirodela polyrhiza was studied to determine the subcellular distribution, chemical forms, and resulting morphophysiological modifications after treatments with 20 or 80 μM Pb(NO) for 10 days. At the subcellular level, the Pb uptake by S. polyrhiza was mainly compartmentalized in the cell walls (70%), and the majority of Pb (approximately 70%) was extracted using 1 M NaCl and 2% acetic acid (HAc).

Competitive interaction with keystone taxa induced negative priming under biochar amendments.

Background: Biochar amendments have been widely proposed as a conventional and efficient strategy to promote soil organic carbon (SOC) sequestration via negative priming. Unfortunately, the extent and biological mechanisms responsible for biochar-induced negative priming are still not fully understood. Despite traditional explanations focused on the environmental filtering mechanisms of biochar amendments on microbial biomass and community composition underlying the priming effect on SOC dynamics, whether and how a biochar-induced competitive interaction with keystone taxa determines SOC mineralization in natural ecosystems has been minimally explored.

Evaluation of cobalt hyperaccumulation and tolerance potential of the duckweed (Lemna minor L.).

Lemna minor could tolerate and accumulate more than 5,000 μg g DW of cobalt (Co) without foliar symptoms, indicating it is a Co hyperaccumulator. However, the physiological and metabolomics mechanisms that are responsible for Co accumulation and tolerance are largely unknown. In the present study, Fourier transform infrared spectroscopy suggested that CO, CH, and OH groups are involved in Co biosorption.

Responses of duckweed (Lemna minor L.) to aluminum stress: Physiological and proteomics analyses.

Aluminum (Al) is commonly considered an abiotic stress factor under acidic conditions. Duckweed (Lemna minor L.) has wide application in ecotoxicological research as a model organism and, in this study, its response to Al bioaccumulation was evaluated at morphological, physiological and proteomic levels.

Alleviation of cadmium toxicity in Lemna minor by exogenous salicylic acid.

Cadmium (Cd) is a significant environmental pollutant in the aquatic environment. Salicylic acid (SA) is a ubiquitous phenolic compound. The goal of this study was to assess the morphological, physiological and biochemical changes in duckweed (L.

Mercury induced oxidative stress, DNA damage, and activation of antioxidative system and Hsp70 induction in duckweed (Lemna minor).

Mercury uptake and its effects on physiology, biochemistry and genomic stability were investigated in Lemna minor after 2 and 6d of exposure to 0-30μM Hg. The accumulation of Hg increased in a concentration- and duration-dependent manner, and was positively correlated with the leaf damage. Oxidative stress after Hg exposure was evidenced in L.

Response of Spirodela polyrhiza to cerium: subcellular distribution, growth and biochemical changes.

Rare earth elements are new and emerging contaminants in freshwater systems. Greater duckweed (Spirodela polyrhiza L.) is a common aquatic plant widely used in phytotoxicity tests for xenobiotic substances.

Molecular distribution and toxicity assessment of praseodymium by Spirodela polyrrhiza.

Aquatic macrophytes are known to accumulate and bioconcentrate metals. In this study, the physiological, biochemical, and ultrastructural responses of Spirodela polyrrhiza to elevated concentrations of praseodymium (Pr), ranging from 0 to 60μM, were investigated over 20 d exposure. The results showed that the accumulation of Pr in S.

Oxidative effects, nutrients and metabolic changes in aquatic macrophyte, Elodea nuttallii, following exposure to lanthanum.

We investigated the phytoremediation potential of Elodea nuttallii to remove rare earth metals from contaminated water. The laboratory experiments were designed to assess the responses induced by lanthanum (5-20mgL(-1)) in E. nuttallii over a period of 7 days.

Bioaccumulation, subcellular, and molecular localization and damage to physiology and ultrastructure in Nymphoides peltata (Gmel.) O. Kuntze exposed to yttrium.

Bioaccumulation, subcellular distribution, and acute toxicity of yttrium (Y) were evaluated in Nymphoides peltata. The effects of Y concentrations of 1-5 mg L(-1) applied for 4 days were assessed by measuring changes in photosynthetic pigments, nutrient contents, enzymatic and non-enzymatic antioxidants, and ultrastructure. The accumulation of Y in subcellular fractions decreased in the order of cell wall > organelle > soluble fraction.

Responses of Hydrilla verticillata (L.f.) Royle to zinc: in situ localization, subcellular distribution and physiological and ultrastructural modifications.

Hydrilla verticillata (L.f.) Royle exposed to 15-150 μM Zn for 7 days were analyzed with reference to the ultrastructural localization, subcellular distribution of metal and its influence on photosynthetic efficiency, malondialdehyde (MDA), adenosine triphosphate (ATP) and ultrastructure.

Copper ultrastructural localization, subcellular distribution, and phytotoxicity in Hydrilla verticillata (L.f.) Royle.

Laboratory experiments were conducted to investigate copper (Cu) subcellular distribution and toxicity in Hydrilla verticillata. Fronds were subjected to different concentrations (15, 75, and 150 μM) of Cu for 7 days. Cu grains were found in cell walls, plasmodesmata, and within the nuclei and chloroplasts using the autometallographic technique.

Laboratory assessment of uptake and toxicity of lanthanum (La) in the leaves of Hydrocharis dubia (Bl.) Backer.

Increasing amounts of lanthanum (La) is released into aquatic environments. However, little information is available on the influence of La on aquatic plants. In this study, physiological and ultrastructural responses of Hydrocharis dubia (Bl.

Subcellular distribution and toxicity of cadmium in Potamogeton crispus L.

The submerged macrophyte Potamogeton crispus L. was subjected to varying doses of cadmium (0, 20, 40, 60 and 80 μM) for 7 d, and the plants were analyzed for subcellular distribution of Cd, accumulation of mineral nutrients, photosynthesis, oxidative stress, protein content, and ultrastructural distribution of calcium (Ca). Leaf fractionation by differential centrifugation indicated that 48-69% of Cd was accumulated in the cell wall.

Involvement of polyamines in adaptation of Potamogeton crispus L. to cadmium stress.

The effects of increasing concentrations of cadmium (Cd) on the ultrastructure, Cd accumulation, generation of O(2)(-), contents of ascorbate (AsA), reduced glutathione (GSH) and polyamines (PAs), as well as the activities of polyamine oxidase (PAO) (EC 1.5.3.

[Roles of exogenous spermidine in improving Salvinia natans tolerance towards cadmium stress].

In this study, the effects of foliar spraying different concentration (0.05-1 mmol L(-1)) spermidine (Spd) on the photosynthetic pigments, soluble protein content, antioxidant system, and mineral nutrition of Salvinia natans leaves under cadmium (Cd) stress were investigated, aimed to approach the action mechanisms of exogenous polyamines (PAs) in improving the adaptability of aquatic plants to heavy metals stress. The results showed that exogenous Spd could markedly mitigate the Cd stress to S.