Plant Level Research Articles

“Hg distribution and accumulation in soil and vegetation in areas impacted by artisanal gold mining in the Southern Amazonian region of Madre de Dios, Peru.”

Artisanal and small-scale gold mining (ASGM) is the primary global source of anthropogenic mercury (Hg) emissions. It has impacted the Amazon rainforest in the Peruvian region of Madre de Dios. However, few studies have investigated Hg's distribution in terrestrial ecosystems in this region. We studied Hg's distribution and its predictors in soil and native plant species from artisanal mining sites. Total Hg concentrations were determined in soil samples collected at different depths (0–5 cm and 5–30 cm) and plant samples (roots, shoots, leaves) from 19 native plant species collected in different land cover categories: naked soil (L1), gravel piles (L2), natural regeneration (L3), reforestation (L4), and primary forest (L5) in the mining sites. Hg levels in air were also studied using passive air samplers. The highest Hg concentrations in soil (average 0.276 and 0.210 mg kg−1 dw.) were found in the intact primary forest (L5) at 0–5 cm depth and in the plant rooting zones at 5–30 cm depth, respectively.Moreover, the highest Hg levels in plants (average 0.64 mg kg−1 dw) were found in foliage of intact primary forest (L5). The results suggest that the forest in these sites receives Hg from the atmosphere through leaf deposition and that Hg accumulates in the soil surrounding the roots. The Hg levels found in the plant leaves of the primary forest are the highest ever recorded in this region, exceeding values found in forests impacted by Hg pollution worldwide and raising concerns about the extent of the ASGM impact in this ecosystem. Correlations between Hg concentrations in soil, bioaccumulation in plant roots, and soil physical-chemical characteristics were determined. Linear regression models showed that the soil organic matter content (SOM), pH, and electrical conductivity (EC) predict the Hg distribution and accumulation in soil and bioaccumulation in root plants.

Assessment of the impact of irrigating with treated wastewater on soil and crop trace metal accumulation

ABSTRACT Water scarcity is growing quickly, especially in the arid and semi-arid regions along with the growing population. So, using treated wastewater in agricultural irrigation presents a sustainable approach, enhancing soil quality, increasing organic carbon levels, and improving crop productivity are achieved through this approach, concurrently reducing the need for chemical fertilizers. Yet, escalating industrial effluent discharge raises concerns regarding trace metals in wastewater and associated health risks. Our study in the Tenth of Ramadan City focused on employing secondary treated mixed industrial and municipal wastewater for olives, mandarins, and guavas. Sampling wastewater, soil, and plant parts, we analyzed their properties and trace element concentrations, employing Visual MINTEQ for geochemical speciation. Adhering to the international guidelines, the wastewater exhibited acceptable pH and alkalinity but showed concerning trace element levels for irrigation. Differences in soil composition and trace element concentrations suggest potential contamination in soils irrigated with wastewater, raising concerns about health risks associated with elevated metal levels in plants. Variations in trace element concentrations in guavas, olives, and mandarins’ leaves and fruits were observed, with efficient translocation in olives, while mandarin and guava displayed reduced efficiency. Bioaccumulation Factor trends indicated species-specific metal uptake differences. Waste “Minimization Prioritization Tool categorized” trace element levels as of low concern. Daily Intake of Trace Metals and Health Risk Index highlighted the need for health risk assessment, especially for elevated Ni in mandarins and guavas. Regression findings emphasized soil factors influencing metal uptake in plants, highlighting the need for vigilant soil management to curb trace element contamination in agriculture, ensuring both food safety and environmental health. Therefore, water reuse adds contributes to sustainable development, which is three dimensions; Economic, Social and Environmental. It improves economics to utilize water that would be otherwise wasted, and by making water more productive. It improves the social dimension by addressing water scarcity and satisfying the increasing water demand for sustainable livelihoods. It also improves the environment by increasing wastewater treatment levels and reducing pollution.

Evaluating the vegetative and reproductive response of hemp (Cannabis sativa) to simulated off-target events of 2,4-D and dicamba

Abstract Introducing soybean cultivars resistant to 2,4-D and dicamba allowed for postemergence applications of these herbicides. These herbicides pose a high risk for off-target movement, and the potential influence on crops such as hemp is unknown. Two studies were conducted from 2020 through 2022 in controlled environments to evaluate hemp response to rates simulating off-target events of 2,4-D and dicamba. The objectives of this study were to: 1) determine the effects of herbicide (2,4-D and dicamba) and rate (1x to 1/100,000x labeled rate) on visible injury, height, and branching, and 2) determine the effect of 2,4-D rate (1x to 1/100,000x labeled rate) on visible injury, height, branching, and reproductive parameters. Herbicides were applied in the early vegetative stage, and evaluations took place 14 and 28 days after treatment (DAT) and at trial termination (42 DAT in the greenhouse trial and at harvest in the growth chamber trial). In the greenhouse trial, 2,4-D and dicamba at the 1x rate and the 1/10x rate caused 68, 78, and 20% injury 28 DAT, respectively. At the time of trial termination 42 DAT, plants treated with 1x rates of 2,4-D and dicamba or 1/10x dicamba were 19, 25, and 9 cm shorter than the nontreated control, respectively. At trial termination, simulated off-target rates of 2,4-D and dicamba did not influence branching or plant weight. In the growth chamber study, the 1x and 1/10x rates of 2,4-D caused 82% and 2% injury 28 DAT, respectively. Plant height, fresh weight, and cannabidiol (CBD) levels of plants treated with simulated off-target rates of 2,4-D were not different from the nontreated control. These studies suggest that hemp grown for CBD exposed to off-target rates of 2,4-D or dicamba in early vegetative stages may not have distinguishable effects 42 DAT or at harvest.

Three species of rape responded to cadmium and melatonin alleviating Cd-toxicity in species-specific strategy

Cadmium (Cd) pollution has been a significant concern in heavy metal pollution, prompting plants to adopt various strategies to mitigate its damage. While the response of plants to Cd stress and the impact of exogenous melatonin has received considerable attention, there has been limited focus on the responses of closely related species to these factors. Consequently, our investigation aimed to explore the response of three different species of rape to Cd stress and examine the influence of exogenous melatonin in this scenario. The research findings revealed distinctive responses among the investigated rape species. B. campestris showed the resistance to Cd and exhibited lower Cd absorption and sustained its physiological activity under Cd stress. In contrast, B. juncea accumulated much Cd and increased the amount of anthocyanin to mitigate the Cd-damage. Furthermore, B. napus showed the tolerance to Cd and tended to accumulate Cd in vacuoles under Cd stress, thereby decreasing the Cd damage and leading to higher activity of antioxidant enzymes and photosynthesis. Moreover, the application of exogenous melatonin significantly elevated the melatonin level in plants and mitigated Cd toxicity by promoting the activity of antioxidant enzymes, reducing Cd absorption, enhancing the chelating capacity with Cd, decreasing Cd accumulation in organelles, and reducing its fluidity. Specifically, exogenous melatonin increased the FHAc content in B. campestris, elevated the phytochelatins (PCs) level in B. napus, and stimulated photosynthesis in B. juncea. In summary, the findings underscore the species-specific responses of the three species of rape to both Cd stress and exogenous melatonin, highlighting the potential for tailored mitigation strategies based on the unique characteristics of each species.

Titanium dioxide nanoparticles alleviates polystyrene nanoplastics induced growth inhibition by modulating carbon and nitrogen metabolism via melatonin signaling in maize.

Nanoplastics, are emerging pollutants, present a potential hazard to food security and human health. Titanium dioxide nanoparticles (Nano-TiO2), serving as nano-fertilizer in agriculture, may be important in alleviating polystyrene nanoplastics (PSNPs) toxicity. Here, we performed transcriptomic, metabolomic and physiological analyzes to identify the role of Nano-TiO2 in regulating the metabolic processes in PSNPs-stressed maize seedlings (Zea mays L.). The growth inhibition by PSNPs stress was partially relieved by Nano-TiO2. Furthermore, when considering the outcomes obtained from RNA-seq, enzyme activity, and metabolite content analyses, it becomes evident that Nano-TiO2 significantly enhance carbon and nitrogen metabolism levels in plants. In comparison to plants that were not subjected to Nano-TiO2, plants exposed to Nano-TiO2 exhibited enhanced capabilities in maintaining higher rates of photosynthesis, sucrose synthesis, nitrogen assimilation, and protein synthesis under stressful conditions. Meanwhile, Nano-TiO2 alleviated the oxidative damage by modulating the antioxidant systems. Interestingly, we also found that Nano-TiO2 significantly enhanced the endogenous melatonin levels in maize seedlings. P-chlorophenylalanine (p-CPA, a melatonin synthesis inhibitor) declined Nano-TiO2-induced PSNPs tolerance. Taken together, our data show that melatonin is involved in Nano-TiO2-induced growth promotion in maize through the regulation of carbon and nitrogen metabolism.

Biochar and silicon relegate the adversities of beryllium stress in pepper by modulating methylglyoxal detoxification and antioxidant defense mechanism.

Industrial activities have escalated beryllium (Be) release in environment which negatively affect plant growth and human health. This investigation describes Be-induced stress in pepper and its palliation by application of pineapple fruit peel biochar (BC) and potassium silicate (Si). The treatment of Be reduced seedling length, biomass, and physiological attributes and enhanced electrolyte leakage, hydrogen peroxide (H2O2), superoxide (O2•-) level in pepper plants; however, these oxidative stress markers were reduced with combined treatment (Be + BC + Si). Application of BC and Si also lowered Be cumulation in roots and shoots of pepper. Under combined treatment, superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) activities exhibited significant enhancement 19, 7.6, 22.8, and 48%, respectively, in Be-stressed pepper. The Be + BC + Si increased peroxidase (POD), glutathione S-transferase (GPX), and glutathione peroxidase (GST) activities 121, 55, and 53%, respectively, as compared to Be-treated pepper. Methylglyoxal level was reduced in pepper with rise in glyoxalase I and II enzymes. Thus, combined application of SS and BC effectively protects pepper against oxidative stress induced by Be by increasing both antioxidant defense and glyoxalase systems. Hence, pineapple fruit peel biochar along with potassium silicate can be used for enhancing crop productivity under Be-contaminated soil.

Recent Advances in Studies of Genomic DNA Methylation and Its Involvement in Regulating Drought Stress Response in Crops.

As global arid conditions worsen and groundwater resources diminish, drought stress has emerged as a critical impediment to plant growth and development globally, notably causing declines in crop yields and even the extinction of certain cultivated species. Numerous studies on drought resistance have demonstrated that DNA methylation dynamically interacts with plant responses to drought stress by modulating gene expression and developmental processes. However, the precise mechanisms underlying these interactions remain elusive. This article consolidates the latest research on the role of DNA methylation in plant responses to drought stress across various species, focusing on methods of methylation detection, mechanisms of methylation pattern alteration (including DNA de novo methylation, DNA maintenance methylation, and DNA demethylation), and overall responses to drought conditions. While many studies have observed significant shifts in genome-wide or gene promoter methylation levels in drought-stressed plants, the identification of specific genes and pathways involved remains limited. This review aims to furnish a reference for detailed research into plant responses to drought stress through epigenetic approaches, striving to identify drought resistance genes regulated by DNA methylation, specific signaling pathways, and their molecular mechanisms of action.

Genetically encoded Boolean logic operators to sense and integrate phenylpropanoid metabolite levels in plants.

Synthetic biology has the potential to revolutionize biotechnology, public health, and agriculture. Recent studies have shown the enormous potential of plants as chassis for synthetic biology applications. However, tools to precisely manipulate metabolic pathways for bioproduction in plants are still needed. We used bacterial allosteric transcription factors (aTFs) that control gene expression in a ligand-specific manner and tested their ability to repress semi-synthetic promoters in plants. We also tested the modulation of their repression activity in response to specific plant metabolites, especially phenylpropanoid-related molecules. Using these aTFs, we also designed synthetic genetic circuits capable of computing Boolean logic operations. Three aTFs, CouR, FapR, and TtgR, achieved c. 95% repression of their respective target promoters. For TtgR, a sixfold de-repression could be triggered by inducing its ligand accumulation, showing its use as biosensor. Moreover, we designed synthetic genetic circuits that use AND, NAND, IMPLY, and NIMPLY Boolean logic operations and integrate metabolite levels as input to the circuit. We showed that biosensors can be implemented in plants to detect phenylpropanoid-related metabolites and activate a genetic circuit that follows a predefined logic, demonstrating their potential as tools for exerting control over plant metabolic pathways and facilitating the bioproduction of natural products.

Water deficit differentially modulates leaf photosynthesis and transpiration of fungus-tolerant Muscadinia x Vitis hybrids.

Screening for drought performance among novel fungi-tolerant grapevine genotypes is a key point to consider in semiarid regions where water scarcity is a common problem during fruit ripening period. It is therefore important to evaluate the genotypes' responses at the level of carbon metabolism and water demand, under water deficit conditions. This study aimed to characterize leaf and plant water use efficiency (respectively named WUEi and WUEpl) of novel INRAE fungi-tolerant genotypes (including LowSugarBerry (LSB) genotypes), under mild and high-water deficit (WD) and to decipher the photosynthetic parameters leading to higher WUEi. For this purpose, experiments were conducted on potted plants during one season using a phenotyping platform. Two stabilized soil moisture capacity (SMC) conditions, corresponding to mild (SMC 0.6) and high (SMC 0.3) WD, were imposed from the onset of berry ripening until the physiological ripeness stage, which was defined as the point at which fruits reach their maximum solutes and water content. At the whole plant level, all genotypes increased WUEpl under high WD. The highest WUEpl was reached for 3176N, which displayed both a high rate of non-structural carbon accumulation in fruits due to high fruit-to-leaf ratio and low plant transpiration because of low total leaf area. However, when normalizing the fruit-to-leaf ratio among the genotypes, G14 reached the highest normalized WUEpl_n under high WD. At the leaf level, WUEi also increased under high WD, with the highest value attained for G14 and 3176N and the lowest value for Syrah. The higher WUEi values for all genotypes compared to Syrah were associated to higher levels of photosynthesis and changes in light-harvesting efficiency parameters (ΦCO2, qP and qN), while no clear trend was apparent when considering the photosynthetic biochemical parameters (Vcmax, Jmax). Finally, a positive correlation between leaf and plant WUE was observed regardless of genotypes. This study allowed us to classify grapevine genotypes based on their grapes primary metabolite accumulation and water consumption during the critical sugar-loading period. Additionally, the study highlighted the potential drought adaptation mechanism of the LSB genotypes.

Edaphic recovery of degraded soils with combined use of leucaena (Leucaena leucocephala) and vetiver grass (Chrysopogon zizanioides) in Vandúzi, Mozambique

Soil recovery is a process aimed at reversing its degradability by incorporating favorable conditions (physical, chemical, and biological) to restructure life so that, through intervention, it can regenerate. This study aimed to analyze the potential combined use of leucaena (Leucaena leucocephala) and vetiver grass (Chrysopogon zizanioides) for the recovery of degraded soils in the Nhamurenguera area, Vandúzi District, Mozambique. The experimental method included soil study (physical-chemical analyses), area preparation (field and seedbed), field management, topographic survey, and qualitative and quantitative visual assessment of the developing seedlings. A total of 650 leucaena and 680 vetiver grass seedlings were planted in an area of 0.5 ha, with a spacing of 4 m between rows and 2 m between seedlings of both species in consort. Three months after planting, the survival and adaptability levels of the seedlings were evaluated. The results showed that 17% of the leucaena individuals and 12% of the vetiver grass died due to ant attacks and insufficient moisture, despite the use of mulching. Regarding the seedlings' reaction to soil conditions, 94% of leucaena and 79% of vetiver showed slow development in the first 3 months of planting due to soil compaction and low nutrient availability (leaching). After four years, soil chemical parameters were evaluated and compared with pre-leucaena/vetiver consortium soil data. The pH values, electrical conductivity, NPK contents, calcium, and magnesium increased, improving soil quality and indicating a soil recovery process to prepare it for subsequent agricultural use, especially for cereal and legume crops.

Interference and economic damage level of volunteer corn plants in soybeans

Interference and economic damage level of volunteer corn plants in soybeans

Assessing the Effectiveness of Pruning in an Olive Orchard Using a Drone and a Multispectral Camera: A Three-Year Study

The uses of precision oliviculture have increased in recent years to improve the quality and quantity of extra virgin olive oil. In traditional and intensive systems, biennial pruning is often applied to balance and maintain plant vigour, aiming at reducing management costs. This study presents the results of a three-year experiment with the objective of quantifying the effects of biennial pruning on the vegetative vigour of olive trees, investigating the geometric and spectral characteristics of each canopy determined with multispectral images acquired by UAV. The experiment was carried out in an olive orchard located in western Sicily (Italy). Multispectral images were acquired using a UAV in automatic flight configuration at an altitude of 70 m a.g.l. The segmentation and classification of the images were performed using Object-Based Image Analysis (OBIA) based on the Digital Elevation Model (DEM) and orthomosaic to extract the canopy area, height, volume and NDVI for each plant. This study showed that the technology and image analysis processing used were able to estimate vigour parameters at different canopy densities, compared to field measurements (R2 = 0.97 and 0.96 for canopy area and volume, respectively). Furthermore, it was possible to determine the amount of removed biomass for each plant and vigour level. Biennial pruning decreased the number of plants initially classified as LV (low-vigour) and maintained a vegetative balance for MV (medium-vigour) and HV (high-vigour) plants, reducing the spatial variability in the field.

Multi-scene application of intelligent inspection robot based on computer vision in power plant

As industries develop, the automation and intelligence level of power plants is constantly improving, and the application of patrol robots is also increasingly widespread. This research combines computer vision technology and particle swarm optimization algorithm to build an obstacle recognition model and obstacle avoidance model of an intelligent patrol robot in a power plant respectively. Firstly, the traditional convolutional recurrent neural network is optimized, and the obstacle recognition model of an intelligent patrol robot is built by combining the connection timing classification algorithm. Then, the artificial potential field method optimizes the traditional particle swarm optimization algorithm, and an obstacle avoidance model of an intelligent patrol robot is built. The performance of the two models was tested, and it was found that the highest precision, recall, and F1 values of the identification model were 0.978, 0.974, and 0.975. The highest precision, recall, and F1 values of the obstacle avoidance model were 0.97, 0.96, and 0.96 respectively. The two optimization models designed in this research have better performance. In conclusion, the two models in this study are superior to the traditional methods in recognition effect and obstacle avoidance efficiency, providing an effective technical scheme for intelligent patrol inspection of power plants.

Single-cell transcriptome profiling reveals the spatiotemporal distribution of triterpenoid saponin biosynthesis and transposable element activity in Gynostemma pentaphyllum shoot apexes and leaves.

Gynostemma pentaphyllum (Thunb.) Makino is an important producer of dammarene-type triterpenoid saponins. These saponins (gypenosides) exhibit diverse pharmacological benefits such as anticancer, antidiabetic, and immunomodulatory effects, and have major potential in the pharmaceutical and health care industries. Here, we employed single-cell RNA sequencing (scRNA-seq) to profile the transcriptomes of more than 50,000 cells derived from G. pentaphyllum shoot apexes and leaves. Following cell clustering and annotation, we identified five major cell types in shoot apexes and four in leaves. Each cell type displayed substantial transcriptomic heterogeneity both within and between tissues. Examining gene expression patterns across various cell types revealed that gypenoside biosynthesis predominantly occurred in mesophyll cells, with heightened activity observed in shoot apexes compared to leaves. Furthermore, we explored the impact of transposable elements (TEs) on G. pentaphyllum transcriptomic landscapes. Our findings the highlighted the unbalanced expression of certain TE families across different cell types in shoot apexes and leaves, marking the first investigation of TE expression at the single-cell level in plants. Additionally, we observed dynamic expression of genes involved in gypenoside biosynthesis and specific TE families during epidermal and vascular cell development. The involvement of TE expression in regulating cell differentiation and gypenoside biosynthesis warrant further exploration. Overall, this study not only provides new insights into the spatiotemporal organization of gypenoside biosynthesis and TE activity in G. pentaphyllum shoot apexes and leaves but also offers valuable cellular and genetic resources for a deeper understanding of developmental and physiological processes at single-cell resolution in this species.

Potential of amino acids-modified biochar in mitigating the soil Cu and Ni stresses – Targeting the tomato growth, physiology and fruit quality

Trace heavy metals (HMs) such as copper (Cu) and nickel (Ni) are toxic to plants, especially tomato at high levels. In this study, biochar (BC) was treated with amino acids (AA) to enhance amino functional groups, which effectively alleviated the adverse effects of heavy metals (HMs) on tomato growth. Hence, this study aimed to evaluate the effect of glycine and alanine modified BC (GBC/ABC) on various tomato growth parameters, its physiology, fruit yield and Cu/Ni uptake under Cu and Ni stresses. In a pot experiment, there was 21 treatments with three replications having two rates of simple BC and glycine/alanine enriched BC (0.5% and 1% (w/w). Cu and Ni stresses were added at 150 mg kg−1 respectively. Plants were harvested after 120 days of sowing and subjected to various analysis. Under Cu and Ni stresses, tomato roots accumulated more Cu and Ni than shoots and fruits, while GBC and ABC application significantly enhanced the root and shoot dry weight irrelevant to the stress conditions. Both rates of GBC decreased the malondialdehyde and hydrogen peroxide levels in plants. The addition of 0.5% GBC with Cu enhanced the tomato fruit dry weight by 1.3 folds in comparison to the control treatment; while tomato fruit juice content also increased (50%) in the presence of 0.5% GBC with Ni as compared to control. In summary, these results demonstrated that lower rate of GBC∼0.5% proved to be the best in mitigating the Cu and Ni stress on tomato plant growth by enhancing the fruit production.

Monitoring and comparative study of 222Rn/220Rn levels in some dwellings nearby Kasimpur Thermal Power Plant, Uttar Pradesh, India

Monitoring and comparative study of 222Rn/220Rn levels in some dwellings nearby Kasimpur Thermal Power Plant, Uttar Pradesh, India

Nullification of GFTs fortifies bioactive folates in foxtail millet.

In foxtail millet (Setaria italica), knockout of the glutamate formiminotransferases SiGFT1 and 2 increased the accumulation of bioactive folates to approximately four times the level of wild-type plants and decreased levels of the bioinactive oxidation product MeFox by 95%, thus providing a promising route for folate biofortification in cereal crops.

Beyond the visible: Accounting for ultraviolet and far-red radiation in vegetation productivity and surface energy budgets.

Photosynthetically active radiation (PAR) is typically defined as light with a wavelength within 400-700 nm. However, ultra-violet (UV) radiation within 280-400 nm and far-red (FR) radiation within 700-750 nm can also excite photosystems, though not as efficiently as PAR. Vegetation and land surface models (LSMs) typically do not explicitly account for UV's contribution to energy budgets or photosynthesis, nor FR's contribution to photosynthesis. However, whether neglecting UV and FR has significant impacts remains unknown. We explored how canopy radiative transfer (RT) and photosynthesis are impacted when explicitly implementing UV in the canopy RT model and accounting for UV and FR in the photosynthesis models within a next-generation LSM that can simulate hyperspectral canopy RT. We validated our improvements using photosynthesis measurements from plants under different light sources and intensities and surface reflection from an eddy-covariance tower. Our model simulations suggested that at the whole plant level, after accounting for UV and FR explicitly, chlorophyll content, leaf area index (LAI), clumping index, and solar radiation all impact the modeling of gross primary productivity (GPP). At the global scale, mean annual GPP within a grid would increase by up to 7.3% and the increase is proportional to LAI; globally integrated GPP increases by 4.6 PgC year-1 (3.8% of the GPP without accounting for UV + FR). Further, using PAR to proxy UV could overestimate surface albedo by more than 0.1, particularly in the boreal forests. Our results highlight the importance of improving UV and FR in canopy RT and photosynthesis modeling and the necessity to implement hyperspectral or multispectral canopy RT schemes in future vegetation and LSMs.

Levels, Distribution and Ecological Risk Assessment of PBDEs in Soils and Plants Around the Engineering Plastics Factory.

This study systematically investigated the pollution levels and migration trends of PBDEs in soils and plants around engineering plastics factory, and identified the ecological risks of PBDEs in the environment around typical pollution sources.The results showed that 13 kinds of PBDEs were widely detected in the surrounding areas, and the concentration level was higher than the general environmental pollution level. The total PBDE concentrations (∑13PBDEs) in soils ranged from 14.6 to 278.4ng/g dry weight (dw), and in plants ranged from 11.5 to 176ng/g dw. Both soil and plant samples showed that BDE-209 was the most important congener, the pollution level in soil and plant was similar, and the composition of PBDEs congener was similar. In the soil column (50cm), the radial migration of PBDEs was mainly concentrated in the 0-30cm section. Except for BDE-66, which was mainly located in the 20-30cm soil layer, the concentration of PBDEs was the highest in the 0-10cm region. Furthermore, the environmental risks of PBDEs in soil and plants were evaluated by hazard quotient method, and the HQ values were all < 1, which did not exhibit any ecological risk. The evaluation results also showed that the ecological risk of PBDEs in soil was higher than that of plants, especially penta-BDE, which should be paid more attention.

The wheat pathogenesis-related protein (TdPR1.2) enhanced tolerance to abiotic and biotic stresses in transgenic Arabidopsis plants.

In plants, the pathogenesis-related (PR) proteins have been identified as important regulators of biotic and abiotic stresses. PR proteins branch out into 19 different classes (PR1-PR19). Basically, all PR proteins display a well-established method of action, with the notable exception of PR1, which is a member of a large superfamily of proteins with a common CAP domain. We have previously isolated and characterized the first PR1 from durum wheat, called TdPR-1.2. In the current research work, TdPR1.2 gene was used to highlight its functional activities under various abiotic (sodium chloride (100mM NaCl) and oxidative stresses (3mM H2O2), hormonal salicylic acid (SA), abscisic acid (ABA) and jasmonic acid (JA), and abiotic stresses (Botrytis cinerea and Alternaria solani). Enhancement survival index was detected in Arabidopsis transgenic plants expressing TdPR1.2 gene. Moreover, quantitative real-time reverse transcription PCR (qRT-PCR) analysis demonstrated induction of antioxidant enzymes such as catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD). It equally revealed a decrease of malondialdehyde (MDA) as well as hydrogen peroxide (H2O2) levels in transgenic Arabidopsis plants compared to control lines, confirming the role of TdPR1.2 in terms of alleviating biotic and abiotic stresses in transgenic Arabidopsis plants. Eventually, RT-qPCR results showed a higher expression of biotic stress-related genes (PR1 and PDF1.2) in addition to a downregulation of the wound-related gene (LOX3 and VSP2) in transgenic lines treated with jasmonic acid (JA). Notably, these findings provide evidence for the outstanding functions of PR1.2 from durum wheat which can be further invested to boost tolerance in crop plants to abiotic and biotic stresses.