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Objectives of this study were to investigate the concentrations, distributions, toxicities, and risk assessment of 16 polycyclic aromatic hydrocarbons in surface soils surrounding a coal chemical industrial zone in the southeast of Shanxi province, China. A total of 52 topsoil samples were collected from different land-use areas: cereal agriculture, roadsides, and parkland. Results show that the total PAHs (∑

Nitrogen (N) loss during composting reduces the quality of compost products and causes secondary environmental pollution. Phthalate esters (PAEs) are common pollutants in agricultural wastes. However, little information is currently available on how PAEs affect N conversion during agricultural waste composting. This research systematically analyzed the impact of di-n-butyl phthalate (DBP) pollution on the N conversion and its related microbial community during composting. Our results indicated that DBP stress results in a shorter thermophilic phase, and then slower compost maturation during composting. Notably, DBP stress inhibited the conversion of ammonia to nitrate, but increased the release of NH

Insect-associated bacteria play an important role in the resistance to pesticides, yet bacterial community compositions in wild insect host populations and the environmental factors that shape them are mostly elusive. In this study, Sitobion miscanthi (Takahashi) populations were collected from major wheat growing regions in China. Following high-throughput sequencing of 16S rRNA gene fragments, association analyses were performed within the bacterial community associated with S. miscanthi, as well as with population resistance levels to four commonly used pesticides and different environmental factors. We found that bacterial community structures differed in various regions, and that the abundances of dominant bacteria such as Buchnera, Candidatus Regiella, Candidatus Hamiltonella showed high variations. The resistance of S. miscanthi to avermectin and bifenthrin was shown to decline with increasing bacterial diversity. Meanwhile, with the increase of bacterial network modularity, the resistance of S. miscanthi populations to imidacloprid, avermectin and bifenthrin also increased correspondingly. In addition, correlation analysis indicated that altitude and air pressure had the strongest impact on bacterial community diversity and relative abundance, followed by humidity, rainfall and temperature. Overall, insights into such complex interactions between bacteria and their insect hosts offer new directions for biological pest control.

Forest canopy cover (FCC) plays an important role in many ecological, hydrological and forestry applications. For large-scale applications, FCC is usually estimated from remotely sensed data by inverting radiative transfer models (RTMs) or using data-driven regressions. In this article, we proposed a hybrid model, which combines a 3-D RTM and transfer learning-based convolutional neural network (T-CNN), to estimate FCC from very high-resolution satellite images (e.g., Chinese GaoFen-2, 1 m resolution with 4 bands). Unlike common hybrid models that are purely trained with simulation data, T-CNN combines simulation data-based pre-training and actual data-based transfer learning, which is a widely used technique in artificial intelligence for fine-tuning models. The performance of T-CNN was compared with a random forest (RF) model and two general CNN models, including CNN trained with actual dataset only (data-CNN) and CNN trained with RTM simulation data only (RTM-CNN). Results on the independent validation dataset (not used in training stage) showed that T-CNN had higher accuracy (RMSE = 0.121, R2 = 0.83), compared with RF (RMSE = 0.26, R2 = 0.61), Data-CNN (RMSE = 0.142, R2 = 0.81), and RTM-CNN (RMSE = 0.144, R2 = 0.73), which indicates that T-CNN has a strong transferability. Tests on different training sizes showed that T-CNN (0.084 < RMSE < 0.108) provided constantly better performances than RF (0.116 < RMSE < 0.122) and data-CNN (0.103 < RMSE < 0.128), which demonstrates the potential of T-CNN as an alternative to RTM-based inversion and data-driven regressions to estimate FCC, especially when training data is imbalanced and inadequate.

Phthalic acid esters (PAEs) pollution has become a major environmental problem in agricultural waste composting. However, little information was available about the how the PAEs alter microbial processes during composting. This study investigated the effects of di-n-butyl phthalate (DBP) on bacterial biomass and community dynamics during composting. The results showed that a decreasing of DBP was observed from thermophilic phase and 43.26% of DBP was degraded after composting. The bacterial biomass and diversity during composting were reduced under DBP stress, so delaying the decomposition of organic matter. Moreover, the changes in bacterial community were observed since the thermophilic phase of DBP-contaminated composting. KEGG pathway analysis indicated that DBP stress decreased the relative abundance of the main metabolic pathways and inhibited compost maturation. Moreover, DBP stress had more significant correlation with the dominant bacteria. This work will expand the understanding of PAEs-contaminated organic waste composting and further control of PAEs pollutants.

The variation of phyllosphere bacterial and fungal communities along elevation gradients may provide a potential link with temperature, which corresponds to an elevation over short geographic distances. At the same time, the plant growth stage is also an important factor affecting phyllosphere microorganisms. Understanding microbiological diversity over changes in elevation and among plant growth stages is important for developing crop growth ecological theories. Thus, we investigated variations in the composition of the rice phyllosphere bacterial and fungal communities at five sites along an elevation gradient from 580 to 980 m above sea level (asl) in the Ziquejie Mountain at the seedling, heading, and mature stages, using high-throughput Illumina sequencing methods. The results revealed that the dominant bacterial phyla were Proteobacteria, Actinobacteria, and Bacteroidetes, and the dominant fungal phyla were Ascomycota and Basidiomycota, which varied significantly at different elevation sites and growth stages. Elevation had a greater effect on the α diversity of phyllosphere bacteria than on that phyllosphere fungi. Meanwhile, the growth stage had a great effect on the α diversity of both phyllosphere bacteria and fungi. Our results also showed that the composition of bacterial and fungal communities varied significantly along elevation within the different growth stages, in terms of both changes in the relative abundance of species, and that the variations in bacterial and fungal composition were well correlated with variations in the average elevation. A total of 18 bacterial and 24 fungal genera were significantly correlated with elevational gradient, displaying large differences at the various growth stages. Soluble protein (SP) shared a strong positive correlation with bacterial and fungal communities (p < 0.05) and had a strong significant negative correlation with Serratia, Passalora, unclassified_Trichosphaeriales, and antioxidant enzymes (R > 0.5, p < 0.05), and significant positive correlation with the fungal genera Xylaria, Gibberella, and Penicillium (R > 0.5, p < 0.05). Therefore, it suggests that elevation and growth stage might alter both the diversity and abundance of phyllosphere bacterial and fungal populations.

Concentrations of heavy metals continue to increase in soil environments as a result of both anthropogenic activities and natural processes. Cadmium (Cd) is one of the most toxic heavy metals and poses health risks to both humans and the ecosystem. Herein, we explore the impacts of Cd on a soil–plant system composed of oilseed rapes (Brassica napus and Brassica juncea) and bacteria. The results showed that Cd accumulation within tissues of two species of oilseed rapes enhanced with increasing concentrations of Cd in soils, and Cd treatment decreased their chlorophyll content and suppressed rapeseeds growth. Meanwhile, Cd stress induced the changes of antioxidative enzymes activities of both B. napus and B. juncea. Response to Cd of bacterial community was similar in soil-two species of oilseed rapes system. The impact of Cd on the bacterial communities of soils was greater than bacterial communities of plants (phyllosphere and endophyte). The α-diversity of bacterial community in soils declined significantly under higher Cd concentration (30 mg/kg). In addition, soil bacterial communities composition and structure were altered in the presence of higher Cd concentration. Meanwhile, the bacterial communities of bulk soils were significantly correlated with Cd, while the variation of rhizosphere soils bacterial communities were markedly correlated with Cd and other environmental factors of both soils and plants. These results suggested that Cd could affect both the growth of plants and the indigenous bacterial community in soil–plant system, which might further change ecosystem functions in soils.

A mixotrophic and acidophilic bacterial strain BGR 140T was isolated from mine tailings in the Harz Mountains near Goslar, Germany. Cells of BGR 140T were Gram-stain-positive, endospore-forming, motile and rod-shaped. BGR 140T grew aerobically at 25–55 °C (optimum 45 °C) and at pH 1.5–5.0 (optimum pH 3.0). The results of analysis of the 16S rRNA gene sequences indicated that BGR 140T was phylogenetically related to different members of the genus Sulfobacillus , and the sequence identities to Sulfobacillus acidophilus DSM 10332T, Sulfobacillus thermotolerans DSM 17362T, and Sulfobacillus benefaciens DSM 19468T were 94.8, 91.8 and 91.6 %, respectively. Its cell wall peptidoglycan is A1γ, composed of meso-diaminopimelic acid. The respiratory quinone is DMK-6. The major polar lipids were determined to be glycolipid, phospholipid and phosphatidylglycerol. The predominant fatty acid is 11-cycloheptanoyl-undecanoate. The genomic DNA G+C content is 58.2 mol%. On the basis of the results of phenotypic and genomic analyses, it is concluded that strain BGR 140T represents a novel species of the genus Sulfobacillus , for which the name Sulfobacillus harzensis sp. nov. is proposed because of its origin. Its type strain is BGR 140T (=DSM 109850T=JCM 39070T).

The phyllosphere, which supports a large number of microorganisms, represents the interface between the aboveground parts of plants and air. In this study, four nifH clone libraries were constructed from the phyllosphere of Pyrus serotina (L), Vitis vinifera (P), Prunus armeniaca (X), and Prunus avium (Y). Clones related to Skermanella (L, 12.1%; X, 15.6%; Y, 62.5%; P 70.8%), Bradyrhizobium (X, 2.1%; P, 15.1%; L, 63.7%), Erwinia (X, 68.8%), Pseudomonas (L, 3.3%; P, 7.6%), and Chroococcidiopsis (P, 0.9%; L, 4.4%, X; 5.2%, Y; 19.6%) were present at high percentages, highlighting their critical role in contributing nitrogen to the phyllosphere ecosystem. The 16S rDNA sequence analysis suggested that phyllosphere-associated bacteria were affiliated with a wide range of taxa, encompassing members from Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Deltaproteobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Cyanobacteria, Tenericutes, and Deinococcus–Thermus. Additionally, the abundance of the nifH gene and 16S rDNA was assessed with quantitative PCR. The number of copies of nifH and 16S rDNA ranged from 1.14 × 103to 1.49 × 104and from 3.72 × 106to 7.02 × 107copies/g fresh leaf sample, respectively. In conclusion, our work sheds light on the microbial communities of the phyllosphere that are important for plant growth. Moreover, we observed a unique composition of nitrogen-fixing bacteria in each phyllosphere sample, suggesting the existence of specific interactions between these functional microorganism and plants, which may provide information or be a reference for the development of bacterial fertilizers.

Mountain systems are unique for studying the responses of species distribution and diversity to environmental changes along elevational gradients. It is well known that free-living diazotrophic microorganisms are important to nitrogen cycling in mountain systems. However, the elevational patterns of free-living diazotrophs and the underlying ecological processes in controlling their turnover along broader gradients are less well documented. Here, we investigated the pattern of diazotrophic diversity along the elevational gradient (1800 m-4100 m) in Mount Gongga of China. The results showed that the α-diversity of diazotrophs did not change with the elevation from 1800 m to 2800 m, but decreased at elevations above 3000 m. Such diversity pattern was driven mainly by soil total carbon, nitrogen, and plant richness. Various diazotrophic taxa showed differential abundance-elevation relationships. Ecological processes determining diazotrophic community assemblage shift along the elevations. Deterministic processes were relatively stronger at both low and high elevations, whereas stochastic processes were stronger at the middle elevation. This study also suggested a strong relationship among aboveground plants and diazotrophs, highlighting their potential interactions, even for free-living diazotrophs.

The exploitation and smelting of rare earths can cause serious pollution to the farmland around the mining area. The rare earth elements (REEs) are absorbed by crops and enter the human body through the food chain, which threatens people’s health. The effects of four phosphorus-containing materials-calcium superphosphate (SSP), phosphate rock (PR), calcium magnesium phosphate (CMP) and bone charcoal (BC) on rice growth and bacterial community structure in REE mining area of Xinfeng County were studied by pot experiment. The soil solution was collected during rice transplanting and harvest periods respectively, the rice and soil samples were collected and sequenced. The concentrations of water-soluble REEs were measured by inductively coupled plasma mass spectrometry (ICP-MS), and bacteria in soil was deeply sequenced by the Illumina Miseq sequencing platform. PR, CMP and BC promoted the growth of rice, improved the biomass of rice roots, shoots and grains, and significantly reduced absorption and accumulation of REEs in rice roots, shoots and grains. SSP treatment reduced the pH value of soil, significantly improved the concentration of REE solution in soil and improved biomass of rice roots, shoots and grains, and significantly improved the concentration of REEs in grain. The effects of phosphorus-containing materials on the absorption and accumulation of 15 REEs in rice roots, shoots and grains were very different, and significantly influenced the soil bacterial community. SSP reduced richness and diversity of bacteria. CMP improved the diversity of soil bacteria, but reduced their richness. PR and BC treatment improved the richness and diversity of soil bacteria, and significantly increased the abundance of Bacillus. The results showed that adding PR, CMP and BC to soil in the REE mining area of Xinfeng can improve food security and eco-environmental quality, and hence, are potential restorative materials; SSP is not recommended for use in acidic soils.

To understand the effects of phthalic acid esters (PAEs) on humic acid (HA) conversion, enzymatic and specific metabolic dynamics during composting under di-n-butyl phthalate (DBP) stress were evaluated for the first time. The results indicated that HA conversion was mainly related to bacteria rather than fungi, with positive associations with Actinobacteria, Chloroflexi, and Gemmatimonadota (all P 0.05), and negative associations with Proteobacteria and Bacteroidota (all P 0.05), while DBP stress retarded HA formation by altering the core microbes related to HA formation and their metabolic functions. Moreover, typical hydrolase and oxidoreductase activities were altered under DBP stress, proteases and cellulases were hindered, and peroxidases as well as polyphenol oxidases were promoted during composting. Overall, our data shows that DBP stress can retard HA formation and compost maturation by interfering with microbial activity. This study provides potentially useful information for the degradation and reuse of PAE-contaminated waste.

Microbial communities associated with the plant phyllosphere and endosphere can have both beneficial as well as detrimental effects on their hosts. There is an ongoing debate to which extend the phyllosphere and endosphere microbiome assembly is controlled by the host plant how pronounced cultivar effects are. We investigated the bacterial and fungal communities from the phyllosphere and endosphere of 10 different rice cultivars grown under identical environmental conditions in the frame of a targeted approach to identify drivers of community assembly. The results indicated that the endophytic bacterial communities were clearly separated into two groups. The α-diversity and microbial network complexity within Group I were significantly lower than in Group II. Moreover, the genera Nocardioides, Microvirga, and Gaiella were significantly more abundant in Group II and only present in the interaction networks of this group. These three genera were significantly correlated with α- and β-diversity of the endophytic bacterial community and thus identified as major drivers of the endosphere community. We have identified keystone taxa that shape endophytic bacterial communities of different rice cultivars. Our overall findings provide new insights into plant-microbe interactions, and may contribute to targeted improvements of rice varieties in the future.

Pot experiments were carried out to study the effects of rice straw (RS) and rice straw ash (RSA) on the growth of early rice and α-diversity of bacterial community in soils around rare earth mining areas of Xunwu and Xinfeng counties in South Jiangxi of China. The results showed that the exploitation of rare earth resources leads to soil pollution around rare earth mining areas and affects the growth of rice, and the content of rare earth elements (REEs) in rice was positively correlated with that in soils and negative correlated with dry weight of rice; The addition of RS to soils around REE mining area can inhibit growth of early rice, and the dry weight of rice grains, shoots, roots is lower when compared with the controls, while the content of REEs is higher. The α-diversity of soil bacterial decreases, which promotes the growth of Pseudorhodoferax, Phenylobacterium and other bacteria of the same kind, and inhibits the growth of beneficial bacteria. The addition of RSA to soils had no significant effect on α-diversity of soil bacterial but promoted the growth of Azospira and other beneficial bacteria, inhibited the growth of Bryobacter and other bacteria of the same kind, significantly improved the dry weight of grains, shoots and roots of early rice, and reduced the content of REEs in these parts of rice. It can be concluded that RS is unsuitable to be added to the planting soil of early rice in REE mining area, while RSA is suitable.

Halosulfuron methyl (HM) is a new, highly active sulfonylurea herbicide that has been widely used for weed control in agricultural production. However, its potential ecological risks remain unknown. In this study, we investigated the impact of different concentrations of HM on bacterial communities in sugarcane rhizospheric soil by using 16S rRNA gene high-throughput sequencing. The half-life of HM for 130 mg/kg, 600 mg/kg, and 1300 mg/kg spraying concentrations were 6.64, 9.19, and 9.87 d, respectively. HM application did not alter the alpha or beta diversity of the soil bacterial community, whereas some microbial populations and the main microbial functional groups were significantly altered by HM exposure. The phylum Cyanobacteria and genus unclassified Chloroflexi group KD4-96 were found to be positively correlated with HM concentration in soils, indicating that they are highly involved in the biodegradation of HM in soils. Relationship analysis between soil properties and microbial communities showed that total nitrogen and total phosphorus concentration were two key factors that significantly influenced microbial community structure. To our best knowledge, this is the first microbial ecotoxicological assessment of HM in agricultural soil.

Plasticizer phthalic acid esters (PAEs) are commonly found as contaminants in various soils. Previous studies indicated that their natural degradation can substantially differ among soil types; however, potential implications of the soil microbiome remained largely unexplored. Here, we have collected ten soil types from nine different geographical regions of China to investigate the degradation of DBP therein and role of bacteria in this process. Results showed that the degradation rate of DBP was lowest in nutrient-poor red soils from Jiangxi Province, while it was highest in fluvo-aquatic soil from Hebei Province. Bacterial community responses to DBP substantially differed in each of the analyzed soils. Arthrobacter is known for its broad-spectrum activity in terms of DBP degradation in soil and was therefore implemented as bioremediating inoculant in many polluted environments. In the present study, network analyses indicated that synergism between soil bacteria increased following exposure to DBP. Arthrobacter and Sphingomonas were found to expand their positive interactions with other members of the microbiome in DBP-contaminated soils. The overall findings of our study provide a basis for biomarker development for detection of DBP contaminations and an extended basis for future bioremediation approaches based on beneficial bacteria.

Waterborne pathogens have attracted a great deal of attention in the public health sector over the last several decades. However, little is known about the pathogenic microorganisms in urban water systems. In this study, the bacterial community structure of 16 typical surface waters in the city of Beijing were analyzed using Illumina MiSeq high-throughput sequencing based on 16S rRNA gene. The results showed that Bacteroidetes, Proteobacteria and Actinobacteria were the dominant groups in 16 surface water samples, and Betaproteobacteria, Alphaproteobacteria, Flavobacteriia, Sphingobacteriia and Actinobacteria were the most dominant classes. The dominant genus across all samples was Flavobacterium. In addition, fifteen genus level groups of potentialy pathogenic bacteria were detected within the 16 water samples, with Pseudomonas and Aeromonas the most frequently identified. Spearman correlation analysis demonstrated that richness estimators (OTUs and Chao1) were correlated with water temperature, nitrate and total nitrogen (p p ≤ 0.05). These results could provide insight into the ecological function and health risks of surface water bacterial communities during the process of urbanization.

In this study, quantitative PCR (qPCR) and high-throughput sequencing were used to simultaneously examine both bacteria and fungi across temporal and spatial scales in activated sludge from wastewater treatment plants (WWTPs). The ratio of fungi to bacteria was 0.43% on average after accounting for the multicopies in 16S rRNA gene (54.63%), indicating the number of fungi was far lower than bacteria in active sludge. The Miseq sequencing results revealed obvious seasonal and spatial variations in bacterial and fungal distribution patterns in WWTPs. Compared to bacteria, fungi showed a lower divergence in alpha and beta diversity, and exhibited less taxonomic diversity in both abundant and rare subcommunities at the class level, suggesting that the fungal community was less variable in this artificial ecosystem. Such variation of microbial communities was significantly correlated with geographical distance, DO, temperature, HRT, SRT, COD, TN and TP. In activated sludge, the main function of bacteria was chemoheterotrophy, fermentation, and nitrogen cycling processes, while the dominant functional guilds of fungi were saprotroph, animal pathogen, and animal endosymbiont. Moreover, both bacteria and fungi could play important roles in the degradation of toxicants, like hydrocarbon and aromatic compounds.

A novel Gram-stain-negative, non-motile, non-spore-forming, rod-shaped, strictly aerobic bacterium, designated strain 13T, was isolated from an activated sludge wastewater treatment plant in Beijing, China. 16S rRNA gene sequence analysis placed this organism within the genus Chitinophaga of the class Bacteroidetes, with Chitinophaga skermanii CC-SG1B (92.4 % gene sequence similarity) and Chitinophaga rupis CS5-B1 (91.2 %) as its closest relatives. This isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and the whole-cell hydrolysate was ribose. Phosphatidylethanolamine was the predominant polar lipid. The major cellular fatty acids were iso-C15 : 0, C16 : 1ω5c and iso-C17 : 0 3-OH. Menaquinone-7 was the only isoprenoid quinone present. The complete genome of the novel strain was sequenced; the size of the genome was 5.28 Mb and the genomic DNA G+C content was 42.5 mol%. The phenotypic, chemotaxonomic and phylogenetic data showed that strain 13T represents a novel species of the genus Chitinophaga , for which the name Chitinophaga caeni sp. nov. is proposed. The type strain is 13T (=CICC 24262T=KCTC 62265T).

Phthalate esters (PAEs) are a type of plasticizer that has aroused great concern due to their mutagenic, teratogenic, and carcinogenic effects, wherefore dibutyl phthalate (DBP) and other PAEs have been listed as priority pollutants. In this study, the impacts of DBP on a soil-vegetable ecosystem were investigated. The results showed that DBP could accumulate within vegetable tissues, and the accumulative effect was enhanced with higher levels of DBP contamination in soils. DBP accumulation also decreased vegetable quality in various ways, including decreased soluble protein content and increased nitrate content. The diversity of bacteria in soils gradually decreased with increasing DBP concentration, while no clear association with endophytic bacteria was observed. Also, the relative abundance, structure, and composition of soil bacterial communities underwent successional change during the DBP degradation period. The variation of bulk soil bacterial community was significantly associated with DBP concentration, while changes in the rhizosphere soil bacteria community were significantly associated with the properties of both soil and vegetables. The results indicated that DBP pollution could increase the health risk from vegetables and alter the biodiversity of indigenous bacteria in soil-vegetable ecosystems, which might further alter ecosystem functions in agricultural fields.

Arsenic (As) contamination is a global problem. Straw incorporation is widely performed in As contaminated paddy fields. To understand how straw and straw biochar incorporation affect As transformation and translocation in the soil-microbe-rice system, a pot experiment was carried out with different dosages of rice straw and straw biochar application. Results showed that both straw biochar and straw application significantly increased As mobility. Straw biochar mobilized As mainly through increasing soil pH and DOM content. Straw incorporation mainly through enhancing As release from iron (Fe) minerals and arsenate (As(V)) reduction to arsenite (As(III)). Straw biochar didn't significantly affect As methylation, while straw incorporation significantly enhanced As methylation, elevated dimethylarsenate (DMA) concentration in soil porewater and increased As volatilization. Straw biochar didn't significantly change total As accumulation in rice grains, but decreased As(III) accumulation by silicon (Si) inhibition. Straw incorporation significantly increased DMA, but decreased As(III) concentration in rice grains. After biochar application, dissolved As was significantly positively correlated with the abundance of Bacillus, indicating that Bacillus might be involved in As release, and As(III) concentration in polished grains was negatively correlated with Si concentration. The significant positive correlation between dissolved As with Fe and the abundance of iron-reducing bacteria suggested the coupling of As and Fe reduction mediated by iron-reducing bacteria. The significant positive correlation between DMA in rice grains and the abundance of methanogenic bacteria indicated that methanogenic bacteria could be involved in As methylation after straw application. The results of this study would advance the understanding how rice straw incorporation affects As fate in soil-microbe-rice system, and provide some guidance to straw incorporation in As contaminated paddy soil. This study also revealed a wealth of microorganisms in the soil environment that dominate As mobility and transformation after straw incorporation.

Lakes are strongly influenced by wind-driven wave turbulence. The direct physical effects of turbulence on bacterioplankton community structure however, have not yet been addressed and remains poorly understood. To examine the stability of bacterioplankton communities under turbulent conditions, we simulated conditions in the field to evaluate the responses of the bacterioplankton community to physical forcing in Lake Taihu, using high-throughput sequencing and flow cytometry. A total of 4,520,231 high quality sequence reads and 74,842 OTUs were obtained in all samples with α-proteobacteria, γ-proteobacteria and Actinobacteria being the most dominant taxa. The diversity and structure of bacterioplankton communities varied during the experiment, but were highly similar based on the same time of sampling, suggesting that bacterioplankton communities are insensitive to wind wave turbulence in the lake. This stability could be associated with the traits associated with bacteria. In particular, turbulence favored the growth of bacterioplankton, which enhanced biogeochemical cycling of nutrients in the lake. This study provides a better understanding of bacterioplankton communities in lake ecosystems exposed to natural mixing/disturbances.

The functioning of microbial communities in response to elevated atmospheric carbon dioxide (eCO2) is one of the most important, but poorly understood, contributors to climate change feedbacks. The effect of soil moisture caused by eCO2 on soil microbial communities and functioning may be of high importance in water limited ecosystems. To address this knowledge gap, we measured the functional composition, structure, and functional processes of soil microbial communities under eCO2 and an irrigation treatment simulating water availability with eCO2 at two soil depths (0–5 cm and 5–15 cm) in a mixed-grass semiarid prairie. The overall functional diversity increased and the microbial composition and structure were significantly (P

A novel actinobacterial strain, designated SDT, was isolated from rhizosphere soil of Chinese cabbage in Shandong province, China. The cells were aerobic, Gram-staining-positive, oxidase- and catalase-positive, short rods and formed white colonies on trypticase soy agar. The cell-wall peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid and alanine, glutamic acid and leucine. Diphosphatidylglycerol was the predominant polar lipid. The predominant cellular fatty acid was C18 : 1ω9c; minor components were anteiso-C15 : 0 and anteiso-C17 : 0. The only isoprenoid quinone was demethylmenaquinone 7 (DMK-7), and the DNA G+C content was 72.7 mol%. Based on the full-length 16S rRNA gene sequence analysis, the closest phylogenetic neighbours of strain SDT were Patulibacter medicamentivorans DSM 25962T (96.9 %), Patulibacter minatonensis DSM 18081T (96.7 %), Patulibacter americanus DSM 16676T (96.2 %) and Patulibacter ginsengiterrae DSM 25990T (95.9 %). Considering combined phenotypic and genotypic characteristics, it is proposed that strain SDT represents a novel species of the genus Patulibacter, for which the name Patulibacter brassicae sp. nov. is proposed. The type strain is SDT (=CICC 24108T=KCTC 39817T).

The phyllosphere, which supports a large number of microorganisms, represents the interface between the aboveground parts of plants and air. In this study, four

The phyllosphere is colonized by a wide variety of microorganisms including epiphytes, plant-pathogenic fungus, bacteria, as well as human or animal pathogens. However, little is known about how microbial community composition changes with the development of angular leaf-spot of cucumber. Here, 18 mixed samples were collected based on the lesion coverage rate (LCR) of angular leaf-spot of cucumber from three disease severity groups (DM1: symptomatic-mild, DM2: symptomatic-moderate, DM3: symptomatic-severe). In our study, the microbial community structure and diversity were examined by Illumina MiSeq sequencing. A significant differences was observed in α diversity and community structure among three disease severity groups. The phyllosphere microbiota was observed to be dominated by bacterial populations from Proteobacteria, Actinobacteria, and Firmicutes, as well as fungal species from Ascomycota and Basidiomycota. In addition, some plant-specific microbe such as Sphingomonas, Methylobacterium, Pseudomonas, and Alternaria showed significant changes in their relative abundance of population. The LCR was correlated negatively with Sphingomonas, Methylobacterium, Quadrisphaera, and Lactobacillus, whereas correlated positively with Pseudomonas and Kineococcus (p