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The Three Gorges Reservoir (TGR) is totally manmade, strongly influenced by anthropogenic activity, and lies on the upper reaches of Yangtze River. The periodic storage and discharge of water from the Three Gorges Dam could have altered the original air-plant/soil interactions of contaminants in TGR. Herein, paired atmospheric gas–particle, air–plant, and air–soil samples were collected to investigate the air–plant interaction and air–soil exchange of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs). The air–plant interaction based on McLachlan's framework to our datasets suggests that PAHs were absorbed via gaseous deposition that was restricted by the plant–gas dynamic equilibrium. The equilibrium indicates a dynamic balance between the gaseous phase and plant surface in PAH absorption. The main limiting factor influencing the PAH uptake was the plant species rather than the atmospheric PAH concentration. The air–soil exchange of PAHs exhibited a net volatilization flux of 16.71 ng/m2/d from the soil to the air based on annual average. There was more volatilization and less deposition in summer and more deposition and less volatilization in autumn and winter. The soil serves as a secondary source of atmospheric PAHs. As the first attempt on probing the multi-interface geochemical process of PAHs, this study highlights the influence of manual water level manipulation from the TGD and environmental factors (such as temperature, humidity, and soil properties) on the regional fate of PAHs in the TGR. [Display omitted] • The PAHs were absorbed via gaseous deposition from the atmosphere. • The main limiting factor influencing the PAH uptake was the plant species. • The soil serves as a secondary source of atmospheric PAHs. • The air–soil exchange exhibited net volatilization from the soil to air. [ABSTRACT FROM AUTHOR]

Classification of wetland plant species (PlatSpe) and surface objects (SurfObj) in remote sensing images faces significant challenges due to the high diversity of PlatSpe and the fragmented nature of SurfObj. Unmanned aerial vehicle (UAV) images and satellite images are the primary data sources for the classification of wetland PlatSpe and SurfObj. However, there is still insufficient research on the effect of various data sources and spatial resolutions on the classification results. This study essentially focuses on Huixian Wetland in Guilin, Guangxi, China through utilizing UAV images and satellite images with varying spatial resolutions as data sources. To this end, the MRS_DeepLabV3+ model is constructed based on multi-resolution segmentation and DeepLabV3+, and the wetland PlatSpe and SurfObj are appropriately classified based on this model. The obtained results reveal that: (1) MRS_DeepLabV3+ model with optimal scale parameter (SP) is capable of achieving higher classification accuracy compared to DeepLabV3+. The optimal SPs for both UAV images and satellite images gradually lessen with decreasing the spatial resolution, and satellite images require larger SPs compared to UAV images. (2) In both the UAV and satellite image models, both OA and kappa exhibit a decreasing trend with the reduction of the spatial resolution. (3) The overall classification accuracies of the satellite image models are superior to the UAV image models in the spatial resolution intervals of 2 to 16 m. This investigation can be regarded as a valuable reference for selecting data sources and spatial resolutions in the wetland PlatSpe and SurfObj classification. • MRS_DeepLabV3+ was constructed based on multi-resolution segmentation and DeepLabV3 +. • Analyzed the impact of scale parameters on the MRS_DeepLabV3+ model. • Investigated the effect of spatial resolution on the classification accuracy. • Compared the differences of classification between UAV images and satellite images. [ABSTRACT FROM AUTHOR]

Orchard pesticide applications using electrostatic spraying technology enhance droplet deposition and reduce environmental pollution. However, the incorporation of charging systems into conventional air-assisted sprayers remains limited. This is primarily due to challenges such as the necessity for high air velocity to prevent droplet adherence to electrodes, electrode-nozzle design flaws, and safety concerns related to the high voltage used for charging. To address these issues, this study developed five charging units that employ insulated induction electrodes, eliminating exposure to external elements. These units were incorporated into an air-assisted sprayer to assess their effectiveness in charging spray droplets and improving deposition. The units successfully limited electrical leakage, even under high-voltage conditions (up to 18 kV) and in the absence of airflow. At an electrode voltage of 14 kV, and an air velocity of 27 m s−1, the electrostatic units achieved an average charge-to-mass ratio of up to 0.67 mC kg−1. Activation of the charging units significantly enhanced droplet deposition with an increase of 90% on the front and 3250% on the back surfaces of the artificial targets (aluminum plates). On real plant leaves, the increase was 54% on the front and 112% on the back surfaces compared with uncharged standard spraying. [Display omitted] • Electrostatic charging units using insulated induction electrodes were successfully developed for air-assisted orchard sprayers. • The insulating layer of electrodes improved the charging efficiency by preventing electrical leakage at high voltage levels. • The electrostatic units mounted on an air-assisted sprayer achieved an average charge-to-mass ratio of 0.67 mC kg−1. • Activation of the charging units increased deposition by 54% and 112% on the front and back surfaces of plant leaves, respectively. [ABSTRACT FROM AUTHOR]

Advanced techniques have been developed to enhance the bioactivity and efficacy of biomedical titanium implants by modifying their surfaces. One such approach involves coating the titanium surface with biomaterials at the nanoscale level. In recent times, medicinal plant extracts have generated attention for nanoparticle synthesis due to their advantageous biomedical properties. Greenly synthesized carob-mediated calcium hydroxide nanoparticles exhibited promising results concerning both anti-inflammatory and osteogenic potentials during in vitro investigations. This study aimed to deposit these nanoparticles onto titanium-alloy bone implants through modifications to the established eco-friendly drop-casting method, characterize the surface, and biomechanically test it on rabbit tibias using torque removal analysis. Surface characterization utilizing scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction analysis successfully coated titanium implants with this material. A biomechanical study conducted on New Zealand rabbits revealed significantly higher peak torque removal values of the coated implants compared to uncoated implants (p < 0.01), suggesting enhanced osseointegration. The drop-casting method employed in this study is a straightforward, cost-efficient, and simple technique for coating various biomaterials onto titanium surfaces. This research lays the groundwork for further exploration of the potential benefits of using calcium hydroxide nanoparticles as titanium bone implant coatings, including their impact on bone healing, bactericidal capabilities, hemostatic potentials, and cellular activities. [ABSTRACT FROM AUTHOR]

A number of pink-pigmented facultative methylotrophs (PPFMs) belonging to Methylobacterium spp. isolated from living plant samples were found to require B vitamins for their growth in minimal medium, and most B vitamin-auxotrophic PPFMs required pantothenate (vitamin B5). Further investigation of pantothenate auxotrophy using the representative strain Methylobacterium sp. OR01 demonstrated that this strain cannot synthesize β-alanine, one of the precursors of pantothenate. β-alanine and several precursors of pantothenate restored the growth of Methylobacterium sp. OR01 in minimal medium. Furthermore, this strain could colonize leaves of Arabidopsis thaliana cultivated in medium without pantothenate or its precursors. Pantothenate, β-alanine and several precursors were detected in the suspension of A. thaliana leaves. These results suggest that pantothenate-auxotrophic PPFMs can symbiotically colonize the surface of plant leaves by acquiring β-alanine and other precursors, in addition to pantothenate. Finally, the fitness advantage of B vitamin auxotrophy of PPFMs in the phyllosphere environment is discussed. [ABSTRACT FROM AUTHOR]

Urban vegetation can alleviate particulate matter (PM) pollution. Many studies examined the PM retention efficiencies of different plant species, but the PM changes retained on leaf surfaces and their effects on plant leaves have rarely been explored. In this study, two common urban greening tree species of the Yangtze River Delta (i.e., Broussonetia papyrifera and Osmanthus fragrans) were selected to explore the compositions of retained PM and assess their adverse impacts on leaf functional traits. Compared with B. papyrifera , O. fragrans with higher wax content was more efficient in particle accumulation, specifically fine (Φ ≤ 2.5 μm) and coarse (2.5 < Φ ≤ 10 μm) particles. The number density and mass concentration of retained PM on plant leaves tended to increase during the accumulation period. Plant species and accumulation time were two major factors to influence particle retention efficiency. Interestingly, the accumulation of particle retention influenced leaf functional traits, such as photosynthesis rate, stomatal conductance, and transpiration rate. The microscopic observations of PM on leaves confirmed that the toxic components of the retained particles potentially caused leaf injury and stomatal damage. Therefore, the acclimation mechanisms of plants responding to the retained urban aerosols should be paid attention in highly polluted areas. [Display omitted] • Osmanthus fragrans with high wax content was efficient in particle retention. • Density and mass of retained particles decreased successively after peaking. • Tree species and accumulation duration significantly affected particle retention. • Particle retention declined the photosynthesis and transpiration rates of trees. • Toxic particles potentially damaged leaf traits and stomatal conductance. [ABSTRACT FROM AUTHOR]

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The perennial evergreen woody shrub, Rhododendron tomentosum , confers associational resistance against herbivory and oviposition on neighbouring plants through passive adsorption of some of its constitutively emitted volatile organic compounds (VOCs). The adsorption process is dependent on transport of VOCs in the air. In polluted atmospheres, the VOCs may be degraded and adsorption impeded. We studied the effect of elevated ozone regimes on the adsorption of R. tomentosum volatiles to white cabbage, Brassica oleracea , and the oviposition of the specialist herbivore Plutella xylostella on the exposed plants. We found evidence for adsorption and re-emission of R. tomentosum volatiles by B. oleracea plants. Ozone changed the blend of R. tomentosum volatiles and reduced the amount of R. tomentosum volatiles recovered from B. oleracea plants. However, plants exposed to R. tomentosum volatiles received fewer P. xylostella eggs than control plants exposed to filtered air irrespective of whether R. tomentosum volatiles mixed with ozone. Ozone disrupts a volatile mediated passive plant-to-plant interaction by degrading some compounds and reducing the quantity available for adsorption by neighbouring plants. The change, however, did not affect the deterrence of oviposition by P. xylostella , suggesting that aromatic companion plants of Brassica crops may confer pest-deterring properties even in ozone-polluted environments. [ABSTRACT FROM AUTHOR]

To further assess the human being's exposure to polycyclic aromatic hydrocarbons (PAHs) through the dietary pathway, understanding the partitioning of these chemicals co-existed with nanomaterials in edible vegetable systems deserves specific consideration. In this study, the fiber-optic fluorimetry was applied to in situ examine the effects of graphene (GNS) and graphene oxide (GO) nanosheets on the quantification and depuration of three-ringed phenanthrene (Phe) and four-ringed fluoranthene (Fla) adsorbed individually onto the living spinach ( Spinacia oleracea L.) surfaces. When the GNS and GO dosages separately increased to the maximum values: a respective red-shift of 4–5 nm and blue-shift of 2–3 nm occurred for the optimal detection emission wavelengths ( λ em ) of the two PAHs, indicating that individual GNS and GO resulted in different changes to the epicuticular wax (ECW) polarity; GNS-inducing fluorescence quenching for the PAHs was about two times greater than GO, owing to the stronger π-π interactions between PAH molecules and GNS relative to GO; the volatilization coefficients ( k C1 ) were reduced by 31.1% versus 26.7% for Phe, and 51.6% versus 34.4% for Fla, mainly via providing an additional adsorbent and promoting the accessibility of the leaf cuticle; respective photolysis coefficients ( k P2 ) of Phe and Fla decreased by 42.9% and 50.0% with GNS, primarily owing to the enhancement of the ECW light-adsorption capacity, but increased by 33.3% and 40.0% with GO due to its photocatalytic activities; overall, total depuration coefficients ( k T1 , k T2 ) of the two PAHs decreased by 11.1–55.6%. These findings demonstrate that GNS and GO significantly alter the depuration behavior of PAHs in vegetable systems, potentially posing a threat to the safety of edible vegetables. [ABSTRACT FROM AUTHOR]

• Quantitative and qualitative description of drop impact onto conifer. • Three types of conifers investigated. • Determination of characteristics of droplets formed after water drop impact. • Influence of conifer properties on the measured quantities. A raindrop may encounter various obstacles on its journey and, as a result of impacts, be broken up into smaller droplets. One such naturally occurring obstacle is the above-ground part of plants. This study presents the impact of a precipitation drop on three selected coniferous shoots that differ in morphology: the eastern hemlock (Tsuga canadensis), the blue spruce (Picea pungens), and the Scots pine (Pinus sylvestris). The falling drops came from a generator and had a diameter of 4.2 mm with a kinetic energy of 0.49 mJ. From the high-speed camera footage, the number and size of droplets formed by the breakdown of an incident drop and the angle at which they travelled were determined. The average number of droplets into which an incident drop broke ranged from 74 to 308, with an average diameter of 0.31 to 0.35 mm, and depended on the species of plant on which the incident drop broke. It was also found that, in the case of the eastern hemlock (Tsuga canadensis), the quantities depended on the location of the drop impact (on the branch or the needles). The size and speed of the droplets after breaking affect the quantity of the throughfall and the rate of water evaporation during falling and from the soil and plant surfaces. The characteristics of the breaking of raindrops into small droplets as a result of hitting branches and leaves can improve our understanding of the role that canopy interception plays in the water cycle. [ABSTRACT FROM AUTHOR]

The continuous use of copper against fungal diseases and off-target effects causes major environmental and agronomic problems. However, the rain-induced removal of Cu-based residues is known only for a limited number of crops. We present the results of rain-induced removal of fungicides from two monitored vineyard plots which were sprayed with two widely used Cu-based formulations: copper-oxychloride (CO) and Bordeaux mixture (BM), respectively. Cu removal per growing season was 0.60±0.12 kg ha −1 (30% of the applied fungicide) for CO and 0.80±0.10 kg ha −1 for BM (70% of the applied fungicide). Fractioning the Cu in soluble (Cu S ) and particulate fractions (Cu P ) showed that most of the Cu was removed as Cu P , but Cu S concentrations found in throughfall collectors exceeded the regulatory threshold for toxicity in surface waters. The first few millimeters of rain caused most of the Cu removal. Our findings agreed with the data reported in the scientific literature, in which a significant fraction of the Cu-based formulation is loosely attached to the plant surfaces. In addition, we found that rainfall energy had a minor influence on the removal. [ABSTRACT FROM AUTHOR]

Arsenic (As) is a toxic metalloid which pollutes soil and water, and negatively affects the growth and development of plants at different levels. This study investigated the effects of As-resistant and plant growth promoting (PGP) bacterial consortia on the germination and growth attributes of two cultivars (Swarna and MTU 1010) of rice (Oryza sativa L.) under As-flooded environment. The consortium consisted of five bacterial strains; Bacillus nealsonii strain ARP2, Pseudomonas nitritireducens strain ARP3, Exiguobacterium aestuarii strain ARRP3, Bacillus tequilensis strain ART2 and Microbacterium paraoxydans strain ADT5, which were isolated from different regions of Chhattisgarh, India. Soils inoculated with the bacterial consortia and supplemented with As(V)/As(III) were used to grow rice seeds under in vitro conditions. The results ascertained that the seedlings inoculated with the bacterial consortia grew well even in the presence of As, which was marked by increased shoot and root length, biomass, and total chlorophyll content. Further, inoculation of bacterial consortia reduced the oxidative stress to a significant level by up-regulating the expressions of protective genes encoding antioxidant enzymes. This consortium could decrease the As accumulation in plants upon successful colonization in the rhizosphere, suggesting possible exploitation of it for enhanced growth of plants and in the remediation of As-contaminated soils. [Display omitted] • Inoculation with five bacterial consortium alleviated the toxic effects of As in Oryza sativa L. • Presence of bacterial strains in the soil limit the uptake of As in seedlings. • Bacterial strains successfully colonized the root surface of plants. • Up-regulation of the expressions of protective genes encoding antioxidant enzymes was observed. • Application of As-resistant PGP bacterial consortium can improve productivity and nutritional values. [ABSTRACT FROM AUTHOR]

A vast variety of microorganisms are supported by plants both aboveground and belowground and such close association may be beneficial in terms of the growth and productivity of the plant. These microbes residing within the biofilm matrix formed on plant surfaces possess unique characteristics. The biofilm bound microbes produce different signals regulated by several physical, biological, and genetic factors. These signals accentuate the plant-microbe chemistry and are predominantly involved in improving the lifestyle of both partners by helping them to thrive under environmental stress. The potential of the plant to endure stress, defend the enemy and acquire resistance through chemical communication is effectively utilized for agricultural betterment with plant growth-promoting rhizobacteria (PGPR). Although the significance of this signalomics and the consequent inter-kingdom co-evolution, are not fully explored, research is going on to analyse these signals and other factors that influence the microbial biofilm formation on plant surfaces with some targeted objectives. [Display omitted] • Mechanism and internal factors affecting the biofilm formation on plant surface is briefly explained. • Several mechanisms of chemical signalling between the plant surface and the bacterial biofilm are described in details. • Different types of association between the bacterial biofilm and plants are elaborated. • Effect of signalling from plant metabolites on biofilm formation is highlighted. • Industrial application of bacterial biofilm association with plant surface is described. [ABSTRACT FROM AUTHOR]

Studies focused on pollutants deposition on vegetation surfaces or aerodynamics of vegetation space conflict in whether vegetation planting can effectively reduce airborne particulate matter (PM) pollution. To achieve a more comprehensive understanding of the conflict, we conducted experiments during 2013 and 2014 in Beijing, China to evaluate the importance of vegetation species, planting configurations and wind in influencing PM concentration at urban and street scales. Results showed that wind field prevailed over the purification function by vegetation at urban scale. All six examined planting configurations reduced total suspended particle along horizontal but not vertical direction. Shrubs and trees–grass configurations performed most effectively for horizontal PM2.5 reduction, but adversely for vertical attenuation. Trapping capacity of PMs was species-specific, but species selection criteria could hardly be generalized for practical use. Therefore, design of planting configuration is practically more effective than tree species selection in attenuating the ambient PM concentrations in urban settings. [ABSTRACT FROM AUTHOR]

Epicuticular wax forms the outermost protective barrier of the aerial surfaces of land plants, working in concert with other components of the plant cuticle to prevent uncontrolled loss of water and to provide protection against an array of external environmental stress. In this study, chemically-mutagenized populations of rice ( Oryza sativa L.) derived from approximately 4 750 M 2 families were screened for adhesion of water droplets resulting in a wet leaf/glossy (wlg) phenotype. Mutants were identified in 11 independently-derived M 2 families. Scanning electron microscopy analysis confirmed the association of the wlg phenotype with changes in the epicuticular wax crystals of these plants. The phenotypes of five mutants (7-17A, 26.1, 524.2, 680.2, and 843.1) were confirmed to be the result of single recessive gene mutation. Evaluation of mutants from 3 (6-1A, 7-17A, and 11-39A) of 11 M 2 families revealed significant reductions (> 50%) in surface wax content and increases in cuticle membrane permeability. [ABSTRACT FROM AUTHOR]

Highlights: [•] Future tree diameters were predicted from past diameters by localizing a mixed-effects model. [•] A second approach involved the use of a set of quantile regression models. [•] Quantile regression based on three quantiles was deemed adequate in predicting diameter growth. [•] Results for mixed-effects and quantile regression models were similar, but mixed model was less biased. [Copyright &y& Elsevier]

Among air pollutants, particulate matter (PM) is considered to be the most serious threat to human health. Plants provide ecosystem services in urban areas, including reducing levels of PM by providing a surface for deposition and immobilization. While previous studies have mostly addressed woody species, we focus on herbaceous roadside vegetation and assess the role of species traits such as leaf surface roughness or hairiness for the immobilization of PM. We found that PM deposition patterns on plant surfaces reflect site-specific traffic densities and that strong differences in particulate deposition are present among species. The amount of immobilized PM differed according to particle type and size and was related to specific plant species traits. Our study suggests that herbaceous vegetation immobilizes a significant amount of the air pollutants relevant to human health and that increasing biodiversity of roadside vegetation supports air filtration and thus healthier conditions along street corridors. [Copyright &y& Elsevier]

• A novel simulation model (UGBE) was developed to assess the cooling performances of urban greenery at street-scale. • The model accounts for the time-varying interactions between plants and anthropogenic heat from buildings and traffic. • Greenery cooling performance is inhibited in a density city, due to limited sunlight and ground-level surfaces for planting. • The latent heat absorption from plants was lower than anthropogenic heat emission. • Greenery should be combined with other strategies to enhance its cooling benefits. How much can greenery cool a city remains inconclusive in literature, especially in a high-density city where plants interact with anthropogenic heat from surrounding buildings and traffic. A novel simulation model, the Urban Greenery and Built Environment, was developed to assess the time-varying interactions between plants and anthropogenic heat at street scale. The model has been evaluated using field studies in two parks in Hong Kong. A reasonably good agreement was observed between measured and predicted temperature and humidity. Sensitivity studies were then conducted to compare the cooling performances of greenery in five scenarios under various coverage ratio and climates. By covering 40% of site with greenery, a practical limit, the expected air temperature and UTCI reductions were 0.3 °C, lower than previous estimates due to limited sunlight and ground-level surfaces for planting; the cooling benefits of greenery were predicted to be higher in dry climates and lower in humid ones. In a high-density city, plants converted sensible heat into latent gains at a slower rate than the anthropogenic exhaust heat. Alternative strategies, such as breeze enhancement, water-spray and management of anthropogenic heat discharges were predicted to further help to cool the city by 3.1 °C, 6.8 °C, and 1.8 °C, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Spray adjuvants have the potential to improve deposition by effecting uniform distribution of the active ingredient on plant surfaces. In order to study whether such a qualitative improvement of spray deposition would lead to improved disease control, a laboratory experiment was conducted on artificially inoculated grapevine (cv. Chardonnay) leaves. Prior to inoculation with Botrytis cinerea conidia in a spore settling tower, leaves were sprayed to pre-runoff with 1mL of a mixture of fenhexamid, a fluorescent pigment, and one of 15 selected commercial adjuvants to manipulate the deposition quality of a specific quantity of spray. Following an incubation period of 24h at high relative humidity, leaf discs were plated onto Petri dishes with paraquat-amended water agar and rated for development of B. cinerea from isolated leaf discs 11d later. Spray deposition on leaves was assessed with a spray assessment protocol using fluorometry, photomicrography and digital image analyses. B. cinerea incidences on the upper and lower surfaces of water-sprayed leaves averaged 90.4% and 95.8%, respectively. Despite full spray cover of leaves, applications with fenhexamid alone did not completely prevent infection and resulted in 34.6% and 40.8% B. cinerea incidences on the upper and lower surfaces of leaves, respectively. Through the addition of certain adjuvants, B. cinerea incidences were significantly reduced (incidences of 2.9–17.1% and 10.0–30.8%, respectively), while some adjuvants did not differ from the fungicide only treatment, even though they might have improved spray deposition. In a histopathology study using epifluorescence microscopy, distinct differences were observed in conidium mortality (20.5% vs. 31.2%), germination (60.4% vs. 51.4%) and germ tube lengths (27.8μm vs. 19.7μm) between Hydrosilicote and Solitaire in combination with fenhexamid, even though both adjuvants effected similar quantitative and qualitative spray deposition. The study clearly demonstrated the potential of adjuvants to improve the bio-efficacy of a fungicide directly through improved deposition on grapevine leaf surfaces, although bio-efficacy might be influenced by adjuvant mode of action in some cases. [Copyright &y& Elsevier]

Abstract: Plant surfaces are characterized by a high diversity of structures which determine their optical properties, such as shiny, gleaming, silky, matt or iridescent. Replicas with different optical properties have been generated by using plant surfaces as templates and an improved replica technique. The technique allows the replication of complex surface structures with overhangs, cavities, and fragile or soft structures in a fast and cost-efficient way. Structures from some millimetres to some nanometres can be replicated. The transfer of complex architectures with different optical properties from plant surfaces onto technical surfaces implies a great potential for the development of new biomimetic surfaces with new optical properties. [Copyright &y& Elsevier]

Abstract: Small wax sculptures on plant surfaces are responsible for a variety of functions, including the maintenance of sability, self-cleaning properties, prevention of insect attachment and reflection of light. Here we report on a method for using recrystallized plant wax crystals on flat technical surfaces for generating micro- and nanopatterned polymers with particular functions. Therefore a more than 4-thousand year old replica technique called the “lost wax technique” has been adapted for reproduction of complex, high aspect ratio surfaces and the large scale reproduction of micro- and nanopatterned surfaces. Highly ordered pyrolytic graphite substrates, covered with perpendicularly oriented platelets formed by the primary alcohol octacosan-1-ol, the main component of wheat (Triticum aestivum) leaf waxes, were used as templates to make an epoxy resin surfaces with high aspect ratio platelets 400–700nm wide and 10–50μm thick. The technique holds great promise on the reproduction of micro- and nanopatterned surfaces. [Copyright &y& Elsevier]

Summary: Cryptococcus is a globally distributed human fungal pathogen that primarily afflicts immunocompromised individuals. How and why this human fungal pathogen associates with plants and how this environmental niche influences its life cycle remains a mystery. We established Cryptococcus-Arabidopsis and Cryptococcus-Eucalyptus systems and discovered that Cryptococcus proliferates and mates on plant surfaces. Mating efficiency of C. gattii was markedly enhanced on plants and myo-inositol and indole acetic acid were specific plant products that stimulated mating. On Arabidopsis, dwarfing and chlorosis were observed following infection with a fungal mixture of two opposite mating-type strains, but not with either mating-type alone. This infection process is countered by the plant jasmonate-mediated defense mechanism. These findings reveal that Cryptococcus can parasitically interact with plants to complete its sexual cycle, which may impact an understanding of the origin and evolution of both plant and animal fungal pathogens in nature. [Copyright &y& Elsevier]

The use of bio-fertilizers in agricultural fields in the form of microorganisms is an eco-friendly way of improving crop yield. The applied microbes, however, face challenges while successfully establishing themselves in the rhizosphere or endosphere of plants due to the competing native soil and plant microflora. To this problem, microbial biofilms are a potential solution as they prolong plant-microbe contacts at various plant surfaces often leading to beneficial outcomes. Microbial biofilms are widely studied due to their adverse impacts in the healthcare sector, water distribution system, food industry, and plant diseases. Recent reports suggest that microbial biofilms may have a positive impact on crop productivity. In this article, we have tried to review the various interactions found between plant and their associated microbes leading to co-metabolic associations and discussed the different ways by which microbes communicate in the microenvironments of the biofilm. Metabolically dependent syntrophic biofilms have been discussed as an area to study in the connection with the agricultural system. Syntrophic biofilms, although less known related to plants may influence the plant growth and yield for a better farming system. • In agricultural fields, microbial inoculants often fail to successfully establish themselves. • Multispecies biofilms in plant roots form stable plant associations. • Biofilms are niche for metabolic dependence and syntrophic communication. • Biofilms may play a crucial role in adopting synthetic farming approaches. • Such a microbe-assisted approach may enhance crop productivity and stress tolerance. [ABSTRACT FROM AUTHOR]

Microplastics and nanoplastics are distributed in the environments universally. The interrelationship between vascular plants and micro/nanoplastics began to attract attention in recent years. Based on the relevant literatures collected from various databases, this review focuses on two topics: 1) the effect of vascular plants on the fate of micro/nanoplastics; 2) the effects of micro/nanoplastics on vascular plants. The review of the available studies reveals that vascular plants can act as sinks for microplastics and nanoplastics as their surfaces can adsorb these plastics; moreover, nanoplastics can be internalized by plants. Plastics on the surfaces and in the interiors of vascular plants can cause various phytotoxicity effects, including impacts on growth, photosynthesis, and oxidative stress. Furthermore, the results and mechanisms of phytotoxicity effects caused by microplastics or nanoplastics can be very different. However, knowledge gaps still exist in the relationships between micro/nanoplastics and vascular plants based on the analysis of available studies; thus, potential subjects for future studies were proposed, including the fates, analysis methods, influencing factors, mechanisms of phytotoxicity, and further influences of microplastics and nanoplastics in the vascular plant ecosystems. This study presents a review of micro/nanoplastics–vascular plant research and reaches a basis for future research. [Display omitted] • Microplastics and nanoplastics can be adsorbed on the surface of vascular plants. • Nanoplastics can be internalized by vascular plants under certain conditions. • Both microplastics and nanoplastics can lead to phytotoxicity on vascular plants, though the mechanisms are different. • The mechanism of phytotoxicity caused by micro/nanoplastics remains to be studied. Microplastics and nanoplastics have significant interactions with vascular plants. [ABSTRACT FROM AUTHOR]

Plastic pollution is a new, pressing, environmental topic. Microplastics are considered contaminants of emerging concern and, consequently, microplastic research has grown exponentially in the last decade. Here, current knowledge regarding the impacts of micro- and nanoplastics on terrestrial plants and aquatic macrophytes is discussed, with a special focus on adsorption, uptake and toxicological effects. Our review reveals that a range of plants and macrophytes can adsorb or internalise plastic particles. Both processes depend on particle characteristics such as size and charge, as well as plant features including a sticky or hydrophobic surface layer. This finding is of concern given that plants and aquatic macrophytes are at the bottom of food webs and are a crucial component of the human diet. Therefore, there is a critical need for improved understanding of adsorption, uptake and impacts of micro- and nanoplastics, and the consequences thereof for trophic transfer, food safety and security. Also, a range of stress responses have been observed for many plant and macrophyte species after both short and long-term exposures to plastic particles. Given that some plastic particles can affect plant productivity, we surmise that plastic particles may potentially impact ecosystem productivity and function. Here we present a synthesis and a critical evaluation of the state of knowledge of micro- and nanoplastics and plants and macrophytes, identifying key questions for future research. [Display omitted] • Micro- and nanoplastics can adsorb externally to plant and macrophyte surfaces. • Nanoplastics and small microplastics can internalise in plant tissues. • Plastic adsorption may have consequences for food safety and ecosystem function. • Studies on the effects of plastics on plants under realistic scenarios are needed. Nano- and microplastics adsorb on plant and macrophyte surfaces. Internalisation appears to be limited to nanoplastics and very small microplastics. Plant stress responses vary depending on experimental conditions. [ABSTRACT FROM AUTHOR]

Part II. Presents the results of an experimental study into the ductile deformations and static and impact perforation of mild steel plates. Comparison of the results with other experimental data; Accuracy of various empirical formulas for the impact perforation of plates.

Part I. Examines the ductile deformation and perforation of plates struck at the center by solid cylindrical projectiles having the longitudinal axis normal to plant surface. Measurement of the steel sheet that the plates are made from; What the plates are clamped around.

To explore the relationship between Al phytotoxicity and the electrochemical characteristics of wheat root surfaces, a new chemical mechanism for tolerance of wheat to Al toxicity was initially proposed by conducting acute root elongation experiment, adsorption/desorption experiment, streaming potential determination, and infrared spectroscopy (ATR-FTIR) analysis respectively to classify the grade of Al tolerance of 92 wheat cultivars and quantitatively characterize the electrochemical properties of their root surfaces. Then a pot experiment was conducted with the screened wheat cultivars with different Al resistance grown on acid soils to verify their tolerance to Al toxicity. Results show that zeta potentials of the roots of 67 wheat cultivars at pH4.46 were significantly negatively correlated with Al(Ⅲ) adsorbed on the roots and their relative root elongation (P < 0.05), indicating that wheat roots with less negative charges is more tolerant to Al toxicity. Based on the mechanism, 14 Al-tolerant, 23 medium Al-tolerant and 30 Al-sensitive wheat cultivars were classified. The pot experiment reveals that the relative dry weight of Al-tolerant wheat cultivars was generally greater than that of medium Al-tolerant and Al-sensitive wheat cultivars and Al-tolerant wheat cultivars accumulate less Al in their shoots, which further verifies the relationship among charge characteristics, tolerance of wheat to Al toxicity, and Al uptake by wheat. The negative charges derived from organic functional groups on root surfaces could influence the exchangeable and complexed Al(Ⅲ) adsorbed on wheat roots and thereby affect Al tolerance of wheat cultivars. This finding not only provides a new perspective to screen Al-tolerant wheat cultivars and explain the mechanism of tolerance of wheat to Al toxicity, but is also useful for the prediction of differences in the uptake of Al in the shoots between Al-tolerant and Al-sensitive wheat cultivars, and finally contributes to the prevention of food security risk caused by Al in acid soils. [Display omitted] • Al-tolerant wheat can be screened based on electrochemical characteristics on roots. • Al-tolerant wheat roots carry less negative charge and fewer functional groups. • Al-tolerant wheat roots adsorb less exchangeable and complexed Al. • Toxic Al shows slight damage to the roots of Al-tolerant wheat cultivars. • Al-tolerant wheat cultivars absorb and accumulate less Al in shoots from acid soils. [ABSTRACT FROM AUTHOR]

The rapid increase in soil acidification rate has led to a decrease in global agricultural productivity owing to the debilitating effects of Al and Mn toxicities. In this study, we investigated the adaptation of plants to acidic conditions by examining the behavior of plant roots grown in hydroponic solution and pot experiments at different pHs. The Mn(II) sorption by the roots was investigated and the mechanisms involved were deduced by analyzing the changes in the zeta potential and functional groups on the root surface. The exchangeable, complexed, and precipitated Mn(II) on plant roots were extracted sequentially with 1 M KNO 3 , 0.05 M EDTA-2Na, and 0.01 M HCl. The results of hydroponic experiment indicated that plant roots subjected to NH 4 + treatment carried lower negative charge and fewer functional groups owing to acidic pH condition induced by NH 4 + uptake of roots, when compared with plant roots treated with NO 3 −. Similarly, in pot experiments, the surface negative charge and functional groups of plant roots cultured in soils with lower pH were fewer than those on plant roots cultured in soils with higher pH, with the former presenting less exchangeable and complexed Mn(II) sorption than the latter. Thus, alterations in the charge properties and number of functional groups on the surface of plant roots are some of the mechanisms used by plants to adapt to acidic soil condition. Image 1 • Plants grown in acid solutions and soils carry less negative charge on their roots. • Plants grown in acid solutions and soils have few functional groups on their roots. • The roots of plants grown in acid conditions adsorbed less exchangeable Mn(II). • Plant roots reduce negative charges and functional groups to adapt acidic soils. [ABSTRACT FROM AUTHOR]

White cabbage, Brassica oleracea , plants and artificial leaves covered with B. oleracea epicuticular wax were exposed to α-pinene and α-pinene oxidation products formed through the oxidation of α-pinene by ozone (O 3) and hydroxyl (OH) radicals. O 3 and OH-induced oxidation of α-pinene led to the formation of oxygenated volatile organic compounds (OVOCs) and secondary organic aerosol particles (SOA), referred to together as oxidation products (OP). Exposure of cabbage plants to O 3 and OH-induced α-pinene OP led to the deposition and re-emission of gas-phase OP by exposed cabbage plants. In a series of 2-choice bioassays, the specialist cruciferous herbivore, Plutella xylostella adults deposited less eggs on artificial leaves exposed to α-pinene OP than on control plants exposed to clean filtered air. P. xylostella larvae did not show a specific feeding preference when offered leaves from different exposure treatments. However, the generalist Indian stick insect, Carausius morosus , fed more on control filtered air-exposed plants than on those exposed to α-pinene OP. Taken together, our results show that exposure to α-pinene oxidation products affects VOC emissions of B. oleracea and alters P. xylostella oviposition and C. morosus feeding responses. Image 1 • O 3 and OH radicals transform α-pinene to less volatile oxidation products (OP). • The α-pinene OP are deposited on and re-emitted by exposed plant. • Exposure to α-pinene OP changes plant VOC profile and alters herbivore responses. • Atmospheric transformation of plant VOC may alter their ecological roles. [ABSTRACT FROM AUTHOR]