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Microbial leftovers, known as necromass, are key players in storing carbon in the soil around plant roots (i.e. rhizosphere), a zone characterized by high‐efficiency microbial anabolism. Yet, the extent and mechanisms through which the rhizosphere contributes to soil organic carbon (SOC) via microbial necromass, especially under changing environments remain unclear. We aimed to evaluate the contributions of microbial necromass to SOC and influencing factors from the rhizosphere perspective. We collected the rhizosphere and bulk soil from 39 alpine coniferous forest sites on the eastern Tibetan Plateau to assess the extent of microbial necromass contribution to SOC in the rhizosphere from a dynamic perspective by calculating the ratio of increased amino sugars (AS) to increased SOC in the rhizosphere relative to that in bulk soil (RAS/SOC). We also collected climate data and determined nutrient concentrations and microbial physiological traits in rhizosphere soil to elucidate the factors affecting RAS/SOC. The results showed that across all sampling sites, the average concentrations of SOC‐normalized AS in the rhizosphere were significantly higher than those in the bulk soil. Furthermore, the average RAS/SOC was greater than 1, indicating a faster microbial necromass accumulation than SOC accumulation in the rhizosphere. These results implied that the rhizosphere sustains a greater capacity for microbial necromass contribution to the SOC pool than the bulk soil does. Soil nutrient availability was the primary factor affecting RAS/SOC, and precipitation indirectly affected microbial anabolism and RAS/SOC by changing soil nutrient status. Additionally, with increasing rhizosphere soil nutrient availability, microbial carbon‐use efficiency and growth rate increased but the biomass‐specific enzyme activity declined, indicating that microorganisms tended to exhibit high‐yield strategies with increasing soil nutrient availability. Synthesis. Our findings underpin the vital effect of microbial necromass in SOC accumulation from the rhizosphere perspective and offer valuable insights into mechanisms underlying microbial C metabolic processes in rhizosphere SOC accumulation under changing environments. [ABSTRACT FROM AUTHOR]

The root system harbours complex bacterial communities, which are critical for plant growth and health. Significant differences exist between bacterial communities in the root compartments; however, limited reports have explored their phylogenetic composition and niche conservatism in the root system of sorghum. We used the sorghum Hongyingzi cultivar as test plant, and applied 16S rRNA high‐throughput sequencing and various statistical approaches. Phylogenetic composition of bacterial communities in root compartments were primarily driven by closely related species with similar environmental adaptations. We also found evidence of phylogenetic niche conservatism in bacterial communities for edaphic factors in the various root compartments, with pH and available N playing essential roles in shaping community composition. Environmental threshold analysis revealed threshold ranges of dominant taxa for pH and available N, indicating wider adaptive thresholds for more abundant taxa. Reconstruction of ancestral states suggested evolutionary changes in adaptability of certain bacterial taxa to edaphic factors, suggesting a shift towards slightly acidic, high N environments and reflecting the prolonged mutual interaction between bacteria and plants in cultivated soils. These findings enhance our understanding of environmental responses and evolutionary dynamics of root‐associated microbiota in young sorghum plants and provide novel insights into ecological adaptations, shedding light on their responses to environmental factors. Our study contributes to a better understanding of the ecological dynamics of root‐associated microbiota and offers analytical pathways for exploring the nutritional regulation of root microbiota. [ABSTRACT FROM AUTHOR]

Grapevine crown gall (GCG), a soil-borne plant disease caused by tumorigenic Allorhizobium vitis (TAV) (=tumorigenic Rhizobium vitis) strains, poses a significant threat to grapevines worldwide. Recently, outbreaks of GCG have been reported in several vineyards, necessitating investigation into potential alternative infection pathways beyond soil transmission. The spatiotemporal distribution of GCG in vineyards from 2020 to 2022 was analyzed using the binary power law (BPL) model, with variations in quadrat shapes. Both total and newly observed diseased plants exhibited an aggregated distribution, indicating that new infections clustered around existing diseased plants, with secondary infections appearing as independent cluster points. This study provides evidence that infected pruning tools can transmit the pathogen to healthy grapevines and that TAV inoculation through spraying contributes more to GCG incidence than planting in infected soil alone. This represents the first documented case of secondary above-ground TAV infection contributing to GCG in commercial vineyards. [ABSTRACT FROM AUTHOR]

Arsenic, a toxic element from both anthropogenic and natural sources, reaches surface environments through atmospheric cycling and dry and wet deposition. Biomethylation volatilizes arsenic into the atmosphere and deposition cycles it back to the surface, affecting soil-plant systems. Chemical speciation of deposited arsenic is important for understanding further processing in soils and bioavailability. However, the range of atmospheric transport and source signature of arsenic species remain understudied. Here we report significant levels of methylated arsenic in precipitation, cloud water and aerosols collected under free tropospheric conditions at Pic du Midi Observatory (France) indicating long-range transport, which is crucial for atmospheric budgets. Through chemical analyses and moisture source diagnostics, we identify terrestrial and marine sources for distinct arsenic species. Estimated atmospheric deposition fluxes of methylated arsenic are similar to reported methylation rates in soils, highlighting atmospheric deposition as a significant, overlooked source of potentially bioavailable methylated arsenic species impacting plant uptake in soils. Analyses of atmospheric samples at a high-altitude site show that methylated forms of arsenic, emitted via biological processes, represent an important share of arsenic deposition. These forms are transported from both marine and terrestrial systems. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is the most essential element for growth, development, and grain yield determination in crops. However, excessive nitrogen application can result in environmental pollution and greenhouse gas emissions that contribute to climate change. In this study, we used 158 rice genetic resources to evaluate the relationships between the soil and plant analysis development (SPAD) value and grain yield (GY) and its components. The SPAD value ranged between 30.5 and 55.8, with a mean of 41.7 ± 5.3, under normal nitrogen conditions (NN, 9 kg/10a), and between 27.5 and 52.3, with a mean of 38.6 ± 4.8, under low nitrogen conditions (LN, 4.5 kg/10a). Under NN conditions, the SPAD values were in the following order: japonica (43.5 ± 5.8), Tongil -type (41.7 ± 2.5), others (41.7 ± 5.2), and indica (38.3 ± 3.8). By contrast, under LN conditions, the SPAD values were in the following order: Tongil -type (40.4 ± 2.1), others (40.1 ± 4.5), japonica (39.6 ± 5.2), and indica (35.6 ± 3.9). The 158 genetic resources showed no correlation between SPAD and yield. Therefore, the low-decrease rate (LDR) and high-decrease rate (HDR) SPAD groups were selected to reanalyze the relationships between the surveyed traits. The SPAD values were positively correlated with 1000-grain weight (TGW) for both LDR and HDR groups (NN: 0.63, LN: 0.53), However, SPAD and GY were positively correlated only in the LDR group. For TGW, the coefficient of determination (R 2) was 20% and 13% under NN and LN conditions, respectively. For GY, R 2 values of 32% and 52% were observed under NN and LN conditions, respectively. Genetic resources with higher SPAD values in the LDR group exhibited the highest yield (NN: 1.19 kg/m2, LN: 1.04 kg/m2) under both NN and LN conditions. In conclusion, we selected 10 genetic resources that exhibited higher GY under both NN and LN conditions with minimal yield reductions. These genetic resources represent valuable breeding materials for nitrogen deficiency adaptation. [ABSTRACT FROM AUTHOR]

Background and Aims The tropical shrub Coelospermum decipiens (Rubiaceae) is an extreme selenium (Se) hyperaccumulator, reported to accumulate up to 1140 µg Se g−1 when found growing on soils with levels of Se below the limit of detection (i.e. <0.01 mg Se kg−1) leading to a bioconcentration factor of >100 000. Methods Coelospermum decipiens plants were sampled from different populations in far north Queensland and analysed for Se concentrations. Plant material was subjected to synchrotron X-ray fluorescence microscopy (XFM) and synchrotron X-ray absorption spectroscopy (XAS) investigations to gain insights into the elemental distribution and chemical speciation of Se. Results The foliar Se concentrations ranged from 100 to 1000 µg Se g−1, except for the seeds, which had up to 28 000 µg Se g−1. The soils from the Hope Vale area were locally Se-enriched up to 48 mg Se kg−1, but there was no relationship between soil and plant Se concentrations. Synchrotron XFM analysis revealed that Se was localized in the blade margin tissue of the younger leaves, whilst the XAS analysis determined that Se occurs as an organo-Se compound. Conclusions We report the occurrence of seleniferous soils in the Cape York Peninsula soils for the first time, which may partly explain the evolution of Se hyperaccumulation in C. decipiens. The extremely high concentrations of Se in the seeds is suggestive of a herbivory protection function. The capacity of this species to accumulate and hyperaccumulate Se from non-seleniferous soils is akin to that of other 'seed'-based accumulators, such as some members of the Lecythidaceae family. [ABSTRACT FROM AUTHOR]

Enzyme-induced calcite precipitation (EICP) is one of the emerging soil improvement methods. However, when plant-based enzyme is used, the urease enzyme harvested from plants cannot be stored long. This affects large-scale applications of this method. This paper presents a new method that not only enables urease enzyme to be stored for a long duration, but also improves significantly the effectiveness and efficiency of EICP for soil improvement. In this method, the storage duration of soybean derived urease enzyme is prolonged by storing it at negative 20 degrees. The experimental results indicated that the frozen-stored urease enzyme had an activity of 326% higher than that of fresh enzyme. The shear strength of a fine sand treated using the frozen-stored enzyme is 238.8% higher than that using a normal EICP method. Thus, the frozen method not only overcomes the enzyme storage problem, but also offers a much-improved EICP method. The reasons for the higher urease activity and improved strength enhancement are also explained in this paper. [ABSTRACT FROM AUTHOR]

Less than 1% of native prairie lands remain in the United States. Located in eastern Washington, the rare habitat called Palouse prairie was largely converted to wheat monocropping. With this conversion came numerous physical, chemical, and biological changes to the soil that may ultimately contribute to reduced wheat yields. Here, we explored how wheat (Tritcum aestivum L.) seedling establishment, plant size, and heading, signifying the developmental transition to flowering, were affected by being planted in prairie soil versus agricultural soils. We then sought to understand whether the observed effects were the result of changes to the soil microbiota due to agricultural intensification. We found that prairie soil enhanced both the probability of wheat seedling survival and heading compared to agricultural soil; however, wheat growth was largely unaffected by soil source. We did not detect effects on wheat developmental transitions or phenotype when inoculated with prairie microbes compared with agricultural microbes, but we did observe general antagonistic effects of microbes on plant size, regardless of soil source. This work indicates that agricultural intensification has affected soils in a way that changes early seedling establishment and the timing of heading for wheat, but these effects may not be caused by microbes, and instead may be caused by soil nutrient conditions. [ABSTRACT FROM AUTHOR]

While the positive species–area relationship on islands is frequently observed, the mechanisms underlying this pattern remain poorly studied. By analyzing insular community diversity across spatial scales and the soil properties within the islands, we were able to explore potential mechanisms leading to the island species–area relationship of plants, as well as associated soil bacteria and fungi, from a tropical archipelago. We found that both plant and soil microbial communities showed similar positive species–area relationships across scales and the greater taxonomic diversity on larger islands was mainly driven by the higher richness within samples. These patterns arose primarily due to shifting habitat quality with island area, rather than spatial processes generally attributed to species–area relationships. Specifically, for plants, changes in soil total phosphorus content with island area were most explanatory, while changes in soil pH appeared to play the most important role in shaping soil bacteria and fungi patterns. By contrast, we found little evidence for the role of spatial processes (i.e. dispersal limitation or soil heterogeneity) within the island. Overall, this study highlights the importance of dissecting potential mechanisms underlying multi‐trophic community dynamics to explain patterns of biodiversity and its variation on islands. [ABSTRACT FROM AUTHOR]

Innovations in plant and soil sciences are revolutionising our approach to sustainability, offering solutions with broad societal impacts. Discoveries in these fields hold great potential for combatting, mitigating and adapting to climate change; enhancing food security; and revitalising urban environments. By harnessing the power of plants and the soils they grow in, it is possible to cultivate resilience in the face of environmental challenges, informing policy and practice, and thereby guiding us towards a more sustainable future. [ABSTRACT FROM AUTHOR]

Background and aims Methods Results Conclusion Low boron (B) availability is associated with strongly weathered, coarse‐textured, and low organic matter soils, widespread in sub‐Saharan Africa (SSA). It is unknown to what extent B fertilization can increase maize yields in SSA. This study aims to understand the soil properties controlling B availability to field‐grown maize.Boron fertilizer omission trials with maize were executed at 15 sites in Kenya, Zambia, and Zimbabwe. Yield, B uptake, and soil parameters potentially relevant for B availability, including extractable soil B (hot water, 0.01 M CaCl2, and 0.43 M HNO3), were determined.Soil B pools were strongly intercorrelated and were positively correlated with organic carbon, suggesting the relevance of organic matter for soil B availability. Soil parameters described limited variation in B uptake and the yield response to B fertilization. Boron fertilization did not increase yields in any of the 15 sites but increased uptake in 11 sites. Yields were reduced through B fertilization in five sites, likely because B application induced toxicity. No clear critical soil or plant B concentrations indicating deficiency could be derived, but positive yield responses to B fertilization were absent with hot water B levels above 0.69 mg kg−1.Assessing B fertilizer needs in maize grown in tropical soils based on soil or plant tissue concentrations remains challenging. Improving soil organic matter status could potentially alleviate B deficiency in crops when present. Recommendations are given to overcome the identified challenges associated with studying B availability in tropical soils. [ABSTRACT FROM AUTHOR]

Background: In China, decline disease with unknown etiology appeared as an epidemic among bayberry trees in the southern area of the Yangtze River. Furthermore, the use of beneficial microbes has been reported to be able to reduce the incidence of this disease, emphasizing the association of this disease with microorganisms. Therefore, it has become critical to uncover the microbiome's function and related metabolites in remodeling the immunity of bayberry trees under biotic or abiotic stresses. Results: The amplicon sequencing data revealed that decline disease significantly altered bacterial and fungal communities, and their metabolites in the four distinct niches, especially in the rhizosphere soils and roots. Furthermore, the microbial communities in the four niches correlated with the metabolites of the corresponding niches of bayberry plants, and the fungal and bacterial networks of healthy trees were shown to be more complex than those of diseased trees. In addition, the role of microbiome in the resistance of bayberry trees to the occurrence of decline disease was justified by the isolation, identification, and characterization of important microorganisms such as significantly enriched Bacillus ASV804, Pseudomonas ASV815 in healthy plants, and significantly enriched Stenotrophomonas ASV719 in diseased plants. Conclusion: Overall, our study revealed that the occurrence of decline disease altered the microbiome and its metabolites in four ecological niches in particular rhizosphere soils and roots of bayberry, which provides new insight into the control of bayberry decline disease. [ABSTRACT FROM AUTHOR]

Global factors are compromising the security of the food supply. Many of us in our community might be unsure about how to help with our seemingly inapplicable expertise. In this piece, I describe how materials chemistry and materials chemists will be essential in addressing this problem, but not only in the way we might think. There is a gigantic and largely unexplored opportunity for real societal impact if we accept a broader view of what academic materials chemistry can be. [ABSTRACT FROM AUTHOR]

Grapevine crown gall (GCG), a soil-borne plant disease caused by tumorigenic Allorhizobium vitis (TAV) (=tumorigenic Rhizobium vitis) strains, poses a significant threat to grapevines worldwide. Recently, outbreaks of GCG have been reported in several vineyards, necessitating investigation into potential alternative infection pathways beyond soil transmission. The spatiotemporal distribution of GCG in vineyards from 2020 to 2022 was analyzed using the binary power law (BPL) model, with variations in quadrat shapes. Both total and newly observed diseased plants exhibited an aggregated distribution, indicating that new infections clustered around existing diseased plants, with secondary infections appearing as independent cluster points. This study provides evidence that infected pruning tools can transmit the pathogen to healthy grapevines and that TAV inoculation through spraying contributes more to GCG incidence than planting in infected soil alone. This represents the first documented case of secondary above-ground TAV infection contributing to GCG in commercial vineyards. [ABSTRACT FROM AUTHOR]

Societal Impact Statement Management practices, for example, in an agricultural context, are often tested in isolation or in pairwise interaction, but rarely using a higher number of jointly applied practices. In a proof‐of‐concept study, we test the effects of combining up to five management practices. Effects seen on soil and plant performance suggest that it may be worth to systematically and broadly examine the effects of higher order management combinations. [ABSTRACT FROM AUTHOR]

Purpose: Interactions between plants and soil biota play an important role in maintaining the productivity and sustainability of agro-ecosystems, but mechanisms responsible for these interactions still are little understood. We investigated the growth of different faba bean genotypes in response to soil decomposer animals in monoculture and mixed cropping system. Methods: In a microcosms experiment, we tested the effects of cropping system (monoculture, mixture with wheat), genotypes (S-62, S-69) and soil decomposers (earthworms, collembolans) on agronomic traits of faba bean. Trait performance and organ biomass of faba bean were evaluated after 100 and 180 days. Results: Genotype S-62 performed better than S-69 for stem, leaf and flowering traits, but it was the opposite for bean biomass. Mixture with wheat reduced most agronomic traits values but not bean biomass for both genotypes. Soil decomposer animals only showed an impact on the S-69 genotype in mixture, with most agronomic traits reduced by 4.6% ~ 19.9% but bean biomass increased by 139.7%. Conclusions: The effect of soil decomposer animals on bean agronomic traits varied between bean genotypes and depended on cropping system. Effects were most pronounced in the genotype allocating more resources to roots and the effects were stronger in mixed cropping systems with wheat. The more pronounced effect of soil decomposer animals in mixed cropping systems was likely due to animals increasing the competitive strength of wheat, thereby suppressing a wide range of bean agronomic traits but not bean biomass. [ABSTRACT FROM AUTHOR]

Novocherkassk Power Station is one of the energy enterprises of the first hazard class, primarily operating on coal, the emissions of which exert a negative impact on the environment of Rostov oblast. The purpose of this study is to analyze the accumulation of Zn, Pb, Cu, Mn, Ni, Cr, and Cd in soils and various types of medicinal plants in its impact zone. The total content of Cr, Ni, and Cd in soils is to 1.4 times higher than the background and the approximately permissible concentrations. It is revealed that the maximal permissible concentration in soils is exceeded by four times for mobile forms of Cu and to two times for mobile Zn, Pb, Ni, and Cr. Heavy metals are mainly accumulated in the above-ground parts of wormwood, common chicory, and tansy and in roots of yarrow. The maximal permissible concentration of elements is exceeded to 3.5 times for Pb, to five times for Cd, and to three times for Ni in yarrow; to 5.5 times for Pb and to two times for Ni in wormwood; to two and six times for Pb and Cd, respectively, in chicory; and to three times for Pb and Cd in tansy. The content of mobile compounds of heavy metals in soil and their accumulation in plants are the highest within 3 km to the northwest from the power station. The degree of technogenic load on soils and medicinal plants in the impact zone is assessed on the basis of biogeochemical parameters. [ABSTRACT FROM AUTHOR]

The percentage of slope classes on a land has an impact on changes in soil physics. The purpose of this study is to evaluate the physical properties of soil planted with tobacco on various slopes in Kenagarian Situjuah Batua, Situjuah Limo Nagari District, Lima Puluh Kota Regency. The method used in this study was a survey; samples were taken purposively based on slope classes at slopes 8−15%, 15–25%, and 25–45% at depths of 0–20 cm and 20–40 cm. From each slope 3 repetitions were taken. The results showed that there were changes in soil physics properties in each slope class with the dominant texture of sandy clay loam. Organic matter was classified as high to low (18.77– 3.63%), low soil buld density (0.66–0.34 g/cm3), and total pore space was classified as high (75.27–86.87%). The permeability of the soil was classified as very fast to somewhat slow (34.88–0.78 cm/h), and the aggregate stability index was somewhat steady to less steady (60.89–45.98%). It is recommended that tobacco farmers to make terrracing and cut the length of the slope so that it does not lose organic matter. [ABSTRACT FROM AUTHOR]

As exotic plants invade into a new range, they can escape from specialist enemies. However, they may support generalist enemies, including both native and introduced fungal pathogens, which creates the potential for spillover and apparent competition from exotic to native plants in communities.To assess the potential for spillover of putatively pathogenic, root‐associated fungi (hereafter, 'pathogens') in communities invaded by exotic plants, we conducted a two‐phase plant–soil feedback experiment: a monoculture experiment with native and exotic plants grown alone and a multi‐species, community‐level experiment that ranged in the extent of exotic dominance. We used next‐generation sequencing to characterise sharing of pathogens between native and exotic plants in communities.Exotic plants outperformed natives in communities, despite harbouring higher relative abundance of generalist pathogens. The higher generalism of pathogens supported by exotic plants made them more prone to be shared with natives. The proportion of pathogens shared between exotic and native plants in communities correlated with reduced competitive ability of native compared with exotic plants.Synthesis: These data suggest that exotic plants host more generalist pathogens that are shared with native plants, which may confer an indirect benefit to exotic over native plants through apparent competition. [ABSTRACT FROM AUTHOR]

A three-year pot experiment was designed to investigate cadmium (Cd) accumulation in the various parts of poplar (Populus deltoides Bartr. cv. 'Lux' I-69/55) by setting up 5 Cd application treatments (0, 5, 20, 50, and 100 mg/kg dry soil). The results showed that poplar exhibited a high tolerance to Cd stress, with Cd uptake significantly increasing across all plant parts as soil Cd levels rose. In general, leaves exhibited the highest Cd concentration while stems had the lowest. An upward increase trend of the accumulation of Cd in the aboveground parts from the base wood, along the stem to the branch, until the leaves, as well as a radially outward increase of Cd from the wood near the pith, to the wood near the bark, and finally to the bark, were observed. Over the three successive years, poplar trees exhibited a generally increasing extraction ability in terms of Cd concentration and the bioconcentration factor (BCF) in their aboveground parts, attributed to the enhanced leaf transpiration and conducting tissue development. The BCFs of various parts of poplar ranged from 0.09 to 6.30, following the trend of leaf > bark > branch > root > stem. [ABSTRACT FROM AUTHOR]

Grounding enhancement material (GEM) is used to lower the earthing resistance value of a given earthing system. In this paper, a commercially available GEM is experimented at the field alongside with Sodium Chloride, Copper II Sulphate and planting soil. The well established Wenner's 4 pole method and fall of potential method was employed to measure the soil resistivity and earthing resistance respectively. It was found that the salts i.e., Sodium Chloride and Copper II Sulphate are superior in reducing the earthing resistance as reduction of more than 85% were observed. However, the commercial GEM has exhibited the most stable earthing resistance value over a period of 101 days, exhibiting the lowest standard deviation. This seems to suggest that the commercial GEM has superior moisture retention capability. This study also proven that Sodium Chloride can be dissolved by heavy downpour and replenishing it periodically is needed in a tropical country like Malaysia with regular thunderstorms and heavy downpours. [ABSTRACT FROM AUTHOR]

Monitoring radioactivity around nuclear power plants is important to avoid the risks of radiation. This study provides an overview of the radioactive emission impact on the near surroundings of the Metsamor nuclear power plant in Armenia. In this context, 29 soil samples were collected from the 40, 80, 120, 160 km radius areas determined in the direction of Iğdır province by accepting the Metsamor nuclear power plant as the center. The activity concentrations of 226Ra, 232Th, 40K and 137Cs in soil samples ranged from 7.90 to 23.44, 7.11 to 33.55, 132.54 to 502.69 and 0.33 to 17.61 Bq/kg, respectively. In addition, the radioactivity concentrations in some agricultural products and the transfer factors from soil to plant were determined. As a result, there is no significant radiological risk in terms of studied radioisotopes for people living in this region. [ABSTRACT FROM AUTHOR]

Organic-based amendments are promising, eco-friendly solutions among soil requalification strategies. In this context, the current study explored the application of compost to Technosols (2 kg m-2) to improve soil quality, making the substrate suitable for plant growth. Changes in soil quality have been assessed before compost addition (time zero, T0) and plant transplanting and at 2, 4 and 11 months (T2, T4, and T11) after plant establishment. To test the soil suitability for plant growth, we monitored (at T2, T4, and T11) structural and functional ecological traits in the herbaceous spontaneous species Malva sylvestris L. and in transplanted Mediterranean sclerophyllous Phillyrea angustifolia L., and Quercus ilex L., often used in the urban greening, also considering plant and soil relationships. Our study demonstrated that compost increased soil nutrients availability over time, favoring M. sylvestris physiological performance in long-lasting, compared to sclerophyllous, since the beginning of the application. M. sylvestris exhibited high photosynthetic efficiency and carbon investment in photosynthetic tissues (higher leaf area and lower leaf mass per area) on compost-enriched soil. On the other hand, P. angustifolia and Q. ilex, even if they did not benefit from compost addition for photosynthetic efficiency, after 11 months, maintained higher leaf water content despite limited soil water availability. These results encourage the use of compost in ameliorating the quality of Technosols for urban greening, also evidencing that the species'choice is pivotal in obtaining benefits from plants and a period longer than one year is needed for sclerophyllous to see beneficial effects. [ABSTRACT FROM AUTHOR]

Bagega community is an artisanal mining community with a history of Pb poisoning. The community is served by a small lake as an important source of water for cattle watering, irrigation, washing, and fishing among other uses. The concentration of Cd, Cr, and Pb in soil and plants at the bank, surface water, sediment, and fish of the lake were analysed using Agilent 4210 MP-AES machine after microwave digestion using the Advanced Microwave Digestion System model (Ethos easy). The concentrations of Pb and Cr in water from Bagega Lake were found to be above the WHO acceptable limits. This presents a health risk to humans and other animals that utilize directly or indirectly utilize the water in the lake. Catfish (Clarias anguillaris) and Tilapia (Oreochromis niloticus) had higher Pb and Cr concentrations in the gills than in the liver and h muscle (flesh). The concentrations of Cr, Cd and Pb of soils in the bank and sediment of Bagega Lake were below the WHO acceptable limits. A total of thirteen (13) plant species belonging to seven (7) families were identified to be dominant around the Bagega Lake during the time of study and they all show the potential of bioaccumulation of Cr and Pb based on their BCF. [ABSTRACT FROM AUTHOR]

Selenium (Se) is one of the essential trace elements for humans. Plants are the main source of Se for humans, while soil Se is the primary source of Se for plants. Biofortification, which involves the transfer of Se from soil to plants and animals, is currently recognized as the safest and most effective approach for Se supplementation for humans. However, Se in soil primarily exists in forms that plants cannot easily utilize, so enhancing Se transfer from soil to plants is crucial for optimal Se utilization. In this paper, we provided a comprehensive analysis of Se forms in soil. Then we summarized the strategies for enhancing Se transfer from soil to plants. These strategies include adjusting redox potential, managing soil moisture, modulating pH value, improving organic matter, optimizing ion competition, promoting beneficial microbes, and considering the synergy between plant rhizosphere and soil. Furthermore, we reviewed Se forms and metabolism after uptake into plants to better understand its role in human health. Finally, we came up with the challenges and perspectives, to provide new insights for further study in this area. This work also offers potential solutions for enhancing Se transformation from soil to plants and utilizing soil Se to produce naturally Se-rich products. [ABSTRACT FROM AUTHOR]

Purpose: GIDI organic fertilizer or water hyacinth is an aquatic plant, an excellent depollutant, and is helpful for food production as compost and regeneration of degraded soil. Maintaining its fertility and maintaining the eco-logical balance of the environment. The study aimed to evaluate the influence of different rates of GIDI organic fertilizer on the yield response of corn under Rebuken, Sultan Kudarat, and Maguindanao conditions from October 2017 to January 2018. Method: Randomized Complete Block Design (RCBD) was used in this study, with five treatments that were replicated three times. The treatments used were as follows: T1- Control or no application of fertilizer, T2- 1,000 kg/ha of GIDI, T3- 2,000 kg/ha GIDI, T4- 3,000 kg/ha of GIDI, and T5- complete and recommended fertilizer in the locale. Results: Based on the findings, the application of different rates of GIDI organic fertilizer significantly influenced the plant height, ear diameter, ear length, thousand seed weight, and grain yield of corn except for ear height in centimeters. Moreover, treatments applied with higher rates of GIDI organic fertilizer obtained the tallest plant height, heaviest seed weight, and grain yield. Conclusion: Results attributed that the GIDI organic fertilizer gives nourishment to plants, enhanced with benefi-cial microbes capable of supplying complete nutrients needed by the corn plants making the soil fertile and yield better. The GIDI organic fertilizer is an environment-friendly, aquatic plant numerously growing in Liguasan Marsh, Rio Grande de Mindanao, Philippines. [ABSTRACT FROM AUTHOR]

Cadmium, a hazardous heavy metal prevalent in plants and soil, poses a significant threat to human health, particularly as approximately 60% of the global population consumes wheat, which can accumulate high levels of Cd through its roots. This uptake leads to the translocation of Cd to the shoots and grains, exacerbating the potential health risks. However, promising results have been observed with the use of moringa leaf extract (MLE) foliar spray in mitigating the adverse effects of Cd stress. The current experiment was conducted to find out the Cd stress tolerance of wheat varieties V1 = Akbar‐19 and V2 = Dilkash‐2020 under exogenous spray of MLE. The treatments of this study were T0 = 0% MLE + 0 µM Cd, T1 = 3% MLE + 0 µM Cd, T2 = 0% MLE + 400 µM Cd, and T3 = 3% MLE + 400 µM Cd. Cd stress demonstrated a significant reduction in morphological attributes as shoot and root fresh weight (22%), shoot and root dry weight (24.5%), shoot and root length (22.5%), area of leaf and number of leaves 30.5%, and photosynthetic attributes (69.8%) in comparison with control. Exposure of wheat plants to Cd toxicity cause oxidative stress, increased H2O2, and MDA up to 75% while foliar application of MLE reduced the activities of reactive oxygen species (ROS). The activity of catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), and ascorbic acid (AsA) increased up to 81.5% as well as organic osmolytes such as phenolics, total soluble proteins, and total soluble sugars were improved up to 77% by MLE applications under Cd stress. Higher accumulation of ionic contents root Na+ (22%) and Cd (44%) was documented in plants under Cd stress as compared to control, while uptake of root mineral ions Ca2+ and K+ was 35% more in MLE‐treated plants. In crux, Cd toxicity significantly declined the growth, photosynthetic, and biochemical parameters while 3% MLE application was found effective in alleviating the Cd toxicity by improving growth and physiological parameters while declining reactive oxygen species and root Na+ as well as Cd uptake in wheat. [ABSTRACT FROM AUTHOR]

In southern China, vegetation on exposed earthen sites serves not only to mitigate erosion but also alters their visual appearance, leading to biodeterioration. However, how plants influence the properties of earthen sites is virtually unknown. This study undertook an ecological investigation of the original habitat in the east city wall of the Sanxingdui site, analyzing its soil properties and investigating plant-soil interactions. Research findings indicate that existing plant communities are not conducive to biodiversity nor site presentation. Plants exert a direct influence within a vertical range extending 0–40 cm beneath the site; root content correlates negatively with soil pH value but positively with organic matter content. The herbaceous community (E-2 and E-3) exhibits higher clay content than the arbor community (E-1) within this range. The above conclusions exhibit statistical significance. This study offers a scientific elucidation of the ecological parameters governing plant communities concerning the conservation of earthen sites, and provides an initial influence range of plant communities and biodegradation on the east city wall of the Sanxingdui sites, thereby revealing the technical potential for employing plants as a soft capping for earthen sites in the open air from the function method. [ABSTRACT FROM AUTHOR]

Some plant species retain mature seeds in plant canopies aboveground which are released later during opportune windows for germination and establishment. This process, known as serotiny, can lead to aerial seedbanks that exist simultaneously with soil seedbanks. However, little is known about how serotiny affects the persistence of weed seeds in the aerial seedbank. A randomized-stratified survey of 117 sites in southern Alberta, Canada, was conducted in 2022 to determine whether the summer-annual tumbleweed Russian thistle (Salsola tragus L.) exhibits seed serotiny. The observational study confirmed that Russian thistle plants exhibit serotiny and that the seeds can exist simultaneously in aerial and soil seedbanks. On average, the plants sampled retained 332 ± 62 viable seeds plant-1 seven to eight months after senescence. This time frame followed winter and emergence of the subsequent generation of plants from the soil seedbank. Russian thistle plants that were attached to the soil retained about double (P = 0.0274) the number of seeds (549 ± 133 viable seeds plant-1) than those detached from the soil (270 ± 71 viable seeds plant-1), likely due to seeds dislodging during movement of the tumbleweeds with prevailing winds. Seeds persisting in aerial seedbanks could evade decay, predation, or lethal germination leading to seed mortality in the soil seedbank, and increase the likelihood of seed persistence and successful establishment of new plants in stressful environments. [ABSTRACT FROM AUTHOR]

Introduction: Pinus tabuliformis as a crucial afforestation species in semi-arid regions, faces issues such as the reduction of plantations. Calcium plays a significant role in alleviating drought stress and promoting nutrient uptake in plants. Methods: Utilizing a pot experiment approach, seedlings were treated with exogenous calcium at five concentrations (0, 50, 100, 200, and 400 mg•kg-1). The nutrient content of the plants and soil was measured, and their ecological stoichiometric characteristics and internal stability were analyzed. This was followed by a series of related studies. Results: As the concentration of calcium increases, the contents of carbon, nitrogen, phosphorus, and potassium in various organs and the whole plant exhibit a trend of first increasing and then decreasing, peaking at calcium treatment of 50-100 mg•kg-1. Concurrently, the calcium concentration in plant organs and the entire plant gradually increases with the availability of calcium in the soil. The addition of exogenous calcium has a certain impact on the ecological stoichiometric ratios (C:N, C:P, N:P) of Pinus tabuliformis seedlings' leaves, stems, roots, and the whole plant, exhibiting distinct variation characteristics. At calcium concentrations of 50-100 mg•kg-1, the ratios of C:N and C:P are relatively lower. Under calcium concentrations of 0, 50, and 100 mg•kg-1, soil calcium shows a positive correlation with the total carbon (TC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), and calcium contents in leaves, stems, roots, and the entire plant. However, at calcium concentrations of 200 and 400 mg•kg-1, soil calcium exhibits a significant positive correlation with the calcium content in leaves, stems, roots, and the entire plant, and a significant negative correlation with the total phosphorus, total nitrogen, total phosphorus, and total potassium contents. After the addition of exogenous calcium at different concentrations, most stoichiometric indices of various organs of Pinus tabuliformis seedlings demonstrate strong balance. Discussion: Calcium, as an essential structural component and second messenger, regulates the nutrient uptake and utilization in plants, influencing the stoichiometry. However, both low and high concentrations of calcium can be detrimental to plant growth by disrupting nutrient metabolism and internal structures. Consequently, there exists an optimal calcium concentration for nutrient absorption. [ABSTRACT FROM AUTHOR]

Summary: Unraveling the mechanisms of home‐field advantage (HFA) is essential to gain a complete understanding of litter decomposition processes. However, knowledge of the relationships between HFA effects and microbial communities is lacking.To examine HFA effects on litter decomposition, we identified the microbial communities and conducted a reciprocal transplant experiment, including all possible combinations of soil and litter, between sites at two elevations in cool‐temperate forests.Soil origin, rather than HFA, was an important factor in controlling litter decomposition processes. Microbiome‐wide association analyses identified litter fungi and bacteria specific to the source soil, which completely differed at a low taxonomic level between litter types. The relative abundance of these microbes specific to source soil was positively correlated with litter mass loss.The results indicated that the unique relationships between plant litter and soil microbes through plant–soil linkages drive litter decomposition processes. In the short term, soil disturbances resulting from land‐use changes have the potential to disrupt the effect of soil origin and hinder the advancement of litter decomposition. These findings contribute to an understanding of HFA mechanisms and the impacts of land‐use change on decomposition processes in forest ecosystems. See also the Commentary on this article by Keiser, 243: 2048–2049. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Pseudostellaria heterophylla, known for its significant bioactive ingredients, offers potential health benefits. Amounts of bioactive compounds of the tuberous root of cultivated Pseudostellaria heterophylla are sensitive to environmental conditions. We selected 22 sampling sites in Guizhou Province, China, a primary Pseudostellaria heterophylla planting area. We analyzed polysaccharides, water‐soluble extractives, total ash and inorganic elements (Fe, Mn, Zn, Mg and Ca) in Radix Pseudostellariae, and pH, organic carbon (OC), available nitrogen (AN), available phosphorus (AP), available potassium (AK) and inorganic elements in the soil.Our study revealed a substantial presence of polysaccharides (85.00–181.00 mg g−1), water‐soluble extractives (47.52–57.63%) and total ash (1.87–3.39%) in Radix Pseudostellariae. Polysaccharides and total ash showed no sensitivity to soil pH. Radix Pseudostellariae collected from soil with pH > 7 exhibited slightly higher levels of water‐soluble extractives, Mg and Ca than that from soil with pH < 5. Conversely, soil with a pH less than 5 had higher OC, AN, AP and AK contents. Water‐soluble extractives in Radix Pseudostellariae were negatively correlated with soil pH but positively correlated with OC and AN.The results imply that the sequestration of soil nutrients over long‐term Pseudostellaria heterophylla cultivation could negatively impact the accumulation of some bioactive ingredients in Radix Pseudostellariae. This study has a profound implication for enhancing the quality of Radix Pseudostellariae of artificially cultivated Pseudostellaria heterophylla. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The transfer of arsenic (As) from soil to plant could be significantly influenced by soil parameters through regulating soil As bioavailability. To distinguish the bioavailable As provided by soil and the As uptaken by plants, herein two different soil bioavailable were defined, namely potential soil bioavailable As (evaluated through the bioavailable fraction of As) and actual soil bioavailable As (assessed through plant bioaccumulation factor, BF, and BFavailable). To identify the dominant soil parameters for the two soil bioavailable As forms, soil and plant samples were collected from a former As mine site. The results showed that the potential bioavailable As only accounted for 1.77 to 11.43% in the sampled soils, while the BF and BFavailable in the sampled vegetables ranged from 0.00 to 1.01 and 0.01 to 17.87, respectively. Despite a similar proportion of As in the residual fraction, soil with higher pH and organic matter (OM) content and lower iron (Fe) content showed a higher potential soil bioavailable As. Correlation analysis indicated a relationship between the soil pH and potential soil bioavailable As (r = 0.543, p < 0.01) and between the soil Fe and actual soil bioavailable As (r = − 0.644, p < 0.05, r = − 0.594, p < 0.05). Stepwise multiple linear regression (SMLR) analysis was employed to identify the dominant soil parameters and showed that soil pH and phosphorus (P) content could be used to predict the potential soil bioavailable As (R2 = 0.69, p < 0.001). On the other hand, soil Fe and OM could be used to predict the actual soil bioavailable As (R2 = 0.18–0.86, p < 0.001–0.015, in different vegetables). These results suggest that different soil parameters affect potential and actual soil bioavailable As. Hence, soil Fe and OM are the most important parameters controlling As transfer from soil to plant in the investigated area. [ABSTRACT FROM AUTHOR]

Legionella longbeachae is the leading cause of Legionnaires' disease (LD) in Australasia and has been linked to exposure to compost and potting soils. Adding antimicrobial metal ions such as copper (Cu2+), zinc (Zn2+), and manganese (Mn2+) to potting soils may reduce the load of L. longbeachae bacteria and infection risk. Baseline concentrations of metal ions in leachate from peat, bark dust, bagging base, and an all-purpose potting soil were: iron 0.40–0.99 µg/ml, Cu of 0.003–0.03 µg/ml, Zn 0.01–0.06 µg/ml and Mn 0.11–0.29 µg/ml. Addition of Cu2+ ions to leachate reduced L. longbeachae viability in a concentration dependent manner. A similar effect was seen in potting soil with Zn2+ and Mn2+ but 10-fold higher concentrations were needed. These metal ions have potential to reduce the load of L. longbeachae in potting soils but toxicity in plants needs to be determined. [ABSTRACT FROM AUTHOR]

Diverse native plant communities resist non‐native plants more than species‐poor communities, in part through resource competition. The role of soil biota in diversity–invasibility relationships is poorly understood, although non‐native plants interact with soil biota during invasions. We tested the responses of non‐native plants to soil biota generated by different native plant diversities. We applied well‐watered and drought treatments in both conditioning and response phases to explore the effects of 'historical' and 'contemporary' environmental stresses. When generated in well‐watered soils, the microbial legacies from higher native diversity inhibited non‐native growth in well‐watered conditions. In contrast, when generated in drought‐treated soils, the microbial legacies from higher native diversity facilitated non‐native growth in well‐watered conditions. Contemporary drought eliminated microbial legacy effects on non‐native growth. We provide a new understanding of mechanisms behind diversity–invasibility relationships and demonstrate that temporal variation in environmental stress shapes relationships among native plant diversity, soil biota and non‐native plants. [ABSTRACT FROM AUTHOR]

Plant–soil feedback (PSF), the reciprocal interaction between plants and their soil environment, is a fundamental ecological process that can influence coexistence and functional structure in plant communities. Current theory establishes that PSF may enhance diversity or lead to exclusion depending on whether soil conditioning disproportionately benefits heterospecific or conspecific individuals. However, a more complete picture of the impact of PSF requires understanding how PSF interacts with competition. To that end, here we propose an integrated mathematical model combining trait‐based competition and soil‐explicit PSF. Contrary to the current paradigm, we find that soil conditioning that disproportionately favours conspecific individuals can promote coexistence. Additionally, we show that priority effects are common when soil‐conditioning species differ in their edaphic preferences. These effects can allow species with large differences in competitive ability to coexist under certain soil conditions. Our results provide testable predictions tying community‐level functional patterns in plant communities to PSF and competition. [ABSTRACT FROM AUTHOR]

This text explores Hegel's perspective on the concept of "ought" and its relationship to morality and possibility. Hegel argues that the "ought" is often given too much importance in moral thought and that it implies an impossibility to fully conform to what is good. He also discusses the role of possibility and actuality in determining what is truly possible, emphasizing that possibility is always determined by actual conditions. However, he does not reject the existence of possibility altogether and acknowledges its presence in different stages of modality. Hegel concludes that practical striving should incorporate the relationship between actuality and possibility, rather than pursuing abstract possibilities divorced from reality. The text also explores Hegel's account of self-grounding and self-conditioning, emphasizing that the self is nothing other than the set of its conditions. Hegel argues that absolute necessity is not self-determining, but rather the actualization of conditions. The text concludes by discussing Hegel's concept of the good, which he sees as a metaphysical category that results from previous determinations. The idea of the good is defined as the unity between concept and reality, and Hegel believes that it corresponds with reality but does not guarantee its realization. The text further explores the tension and obstacles in achieving the good, suggesting that it is an ongoing process rather than a static ideal. [Extracted from the article]

Hydrazidase from Microbacterium hydrocarbonoxydans was revealed to catalyze synthetic hydrazide compounds, enabling the bacteria to grow with them as a sole carbon source, but natural substrates have remained unknown. In this study, kinetic analyses of hydrazidase with parabens showed that the compounds can be substrates. Then, methylparaben induced gene expressions of the operon containing hydrazidase and ABC transporter, and the compound as a sole carbon source was able to grow the bacteria. Furthermore, homology search was carried out revealing that several actinomycetes possess hydrazidase homologs in the operon. Among those bacteria, an amidase from Pseudonocardia acaciae was subjected to a kinetic analysis and a structure determination revealing similar but not identical to those of hydrazidase. Since parabens are reported to exist in plants and soil, and several actinomycetes code the homologous operon, the enzymes with those operons may play a physiologically important role for bacterial survival with use of parabens. [ABSTRACT FROM AUTHOR]

This study was conducted in the territory of the industrial site of the Udachny Mining and Processing Division (Yakutia, Russia). The objects of study were permafrost soils and two species of shrubs (Betula middendorffii T. and Duschekia fruticose R.). Soil and plant samples were analyzed by atomic absorption spectrometry for the presence of potentially toxic elements (Pb, Ni, Mn, Cd, Co, Co, Cr, Zn, Cu, and As). The bioaccumulation factor for each element was also calculated. In the studied plants, the investigated elements were arranged in the following descending row in terms of their content: Mn > Zn > Cr > Ni > Cu > Pb > As > Co > Cd, but in terms of bioaccumulation degree, they decrease in the following row: Cr > Zn > Ni > Mn > Pb > Cu > Cd > Co—for Betula middendorffii, Cr > Zn > Ni > Pb > Cu > Mn > Mn > Cd > Co—for Duschekia fruticose. The bioaccumulation factor results confirmed that Betula middendorffiii and Duschekia fruticosa are resistant to high concentrations of Cr, Ni, Co, Cu, Mn, and Zn elements coherent to kimberlites. [ABSTRACT FROM AUTHOR]

Radioactive radium (Ra) mainly comes from the mining and milling of uranium and other metal or non-metal mines, phosphate production and fertilizer use, production of oil and gas, coal combustion, wastewater treatment, and various wastes from the above activities, which is ubiquitous in the environment. Phytoremediation is a green and cheap remediation technology for metal/radionuclide-contaminated sites. Radium is often of particular interest and there are many literatures on parameters of Ra concentration in plants and transfer factors from soil to plant from a radiological impact assessment point of view. However, review articles on phytoremediation of Ra-polluted soil are relatively few. This review focused on radium-polluted soil phytoremediation, involving two main strategies of phytoextraction and phytostabilization, which covered the potential (hyper)accumulators for Ra, characteristics of Ra uptake from soil by plants, influencing factors, and phytostabilization application. In future research works, more attention should be paid to the deep insights and mechanism researches of Ra uptake/immobilization by plants. This review will deepen the understanding of the relationship of radium-soil-plants, and to enhance the potential application of phytoremediation as an alternative treatment technology for remediation of Ra-polluted soil site. [ABSTRACT FROM AUTHOR]

The study is aimed at assessing the impact of biochar on the phytoaccumulation of heavy metals by okra and fluted pumpkin plants in soil polluted with petroleum hydrocarbons, and its corresponding environmental and health‐related risks. A field experiment was conducted at the automobile workshop (commonly called mechanic village) using a randomized complete block design (RCBD). The field was divided into plots and three replicates. Maize stalk biochar (MSB) and nipa palm biochar (NPB) were treated differently in each plot at a rate of 20 t ha−1. Plots containing no biochar were used as controls. The soil samples were analyzed for petroleum hydrocarbon content (PHCt), selected heavy metals as well as some other soil physicochemical properties. Plant samples were only analyzed for heavy metal contents. Analysis of variance was used to analyze the data generated. The PHCt and heavy metal content in the soil were compared with the target values set by the Department of Petroleum Resources of Nigeria whereas heavy metals in plants were compared with FAO/WHO guidelines. Okra and fluted pumpkin were evaluated for phytoaccumulating potential using bioaccumulation factor (BAF). Ecological risk assessment was done using a hazard quotient (HQ). The PHCt, cadmium (Cd), chromium (Cr), and nickel (Ni) were significantly decreased following the application of biochar. The NPB recorded the lowest values for PHCt (64.4 mg kg−1), lead (16.0 mg kg−1), and Ni (12.8 mg kg−1) contents while MSB had the lowest values for Cd (0.3 mg kg−1) and Cr (7.6 mg kg−1) contents. The HQ analysis showed that Cr (2.93 mg kg−1) and Pb (156.83 mg kg−1) posed a very high ecological risk to the local ecosystem. The phytoaccumulated heavy metals in plants were above the maximum allowable levels, except Ni where the content was below the maximum allowable levels. Fluted pumpkin had the highest BAF values for Cd, Cr, Pb, and Ni. Therefore, fluted pumpkin can be used as an efficient phytoremediator for soil contaminated with Cd, Cr, Pb, and Ni. [ABSTRACT FROM AUTHOR]

Three new α-pyrone derivatives, annularins L–N (1–3), were isolated from the EtOAc extract of Penicillium herquei MA-370, a fungus obtained from the rhizospheric soil of the mangrove plant Rhizophora mucronata. The planar structures of compounds 1–3 were determined based on comprehensive spectral interpretation of the NMR and MS data. The absolute configuration of 1 was determined by X-ray crystallographic data and that of 2 was assigned by TDDFT calculations of its ECD spectrum and cotton effects comparison with those of 1. The antimicrobial activity of compounds 1–3 was evaluated. [ABSTRACT FROM AUTHOR]

This work aims to assess the bioavailability and bioaccumulation of Cr, Cu, Pb, and Zn in the soil–plant system (Erigeron canadensis L.) in the zone of anthropogenic impact in Dnipro city, a significant industrial and economic centre of Ukraine. Sampling was carried out at three locations at distances of 1.0 km, 5.5 km, and 12.02 km from the main emission sources associated with battery production and processing plants in Dnipro. The concentrations of heavy metals such as Cr, Cu, Pb, and Zn were analysed using atomic emission spectrometry from soil and parts of Erigeron canadensis L. The highest concentrations of elements in the soil, both for the mobile form and the total form, were determined to be 48.96 mg kg−1 and 7830.0 mg kg−1, respectively, for Pb in experimental plot 1. The general ranking of accumulation of elements in all experimental plots, both for the plant as a whole and for its parts, was as follows: Zn > Cu > Cr > Pb. Zn for plants was the most available heavy metal among all studied sites and had the highest metal content in the plant (339.58 mg kg−1), plant uptake index (PUI-506.84), bioabsorption coefficient (BAC-314.9), and bioconcentration coefficient (BCF-191.94). According to the results of the study, it is possible to evaluate Erigeron canadensis L. as a hyperaccumulator of Zn, Cu, and Cr and recommend it for phytoextraction of soils contaminated with Zn, Cu, and Cr and phytostabilization of soils contaminated with Pb. [ABSTRACT FROM AUTHOR]

In this study, the activity concentration of NORMs were measured using gamma spectrometer, based on NaI(Tl) detector with Maestro-32 installed computer soft- ware. Accordingly, the average activity concentrations of 232Th, 238U, and 40K in soil samples were found 17.85±0.50, 40.16±0.54, and 271.46±0.07, respectively, which are lower than the average world recommended values given by UNSCEAR 2000 for Th and K, but higher for U decay series. In the same way, activity concentration of NORMs in food items cultivated from the irrigation site were measured and the highest activity concentrations were observed in bean samples. The transfer factors of 232Th, 238U and 40K from soil to food items were computed based on the measured activity values, and in most food items it is observed above the world average values. The consecutive chronic daily intake via ingestion for some food items from samples are also above the permissible limit. The transfer factor from Gerado agricultural soil to plant exceed the world average values in the cases of 232Th and 238U according to our study. [ABSTRACT FROM AUTHOR]

Trichotylenchus sp. is a migratory ectoparasitic nematode (PPN) that causes hypoplasia disease symptoms in economic plants, such as maize and banana. In this study, soil samples were collected from 6 locations in a tomato field in Khon Kaen Province, Thailand, for the purpose of nematode extraction using the Cobb's sieving and flotation-centrifugation techniques. Morphological and molecular characterization of the collected PPN identified it as Trichotylenchus sp., a PPN not previously found in Thai tomato fields. Morphologically, the nematode has a C-shaped body, a rounded lip region, robust stylet and dorsal gland orifice located 2.0 ± 0.5 µm from the base of basal knobs. The tail is conically shaped, and the cuticle exhibits annulations with 3 incisures in the lateral field. The morphological characteristics observed closely matched Trichotylenchus sp. To confirm the identity, diagnosis was done using Polymerase Chain Reaction (PCR) molecular technique. Nematode DNA amplification was conducted with different target genes using primer sets AB28/TW81 for ITS1-5.8S-ITS2 and D2A/D3B for D2-D3 region of the 28S rRNA. The PCR amplification showed DNA fragments of approximately 950 and 800 bp, respectively. The sequences obtained were compared with those in the NCBI GenBank, which showed a 98.0 - 99.4 % identity match with Trichotylenchus dispersus specimens previously documented in China. In addition, the phylogenetic trees reiterated a nematode grouping with T. dispersus, 100 % bootstrap value. To the best of our knowledge, this is the first report of the presence of T. dispersus in the soils of tomato field in Thailand. This nematode is likely to become a major factor limiting tomato production yields if not properly managed. [ABSTRACT FROM AUTHOR]

Brazil is the largest coffee-producing nation in the world. Over 50% of the national production comes from the Minas Gerais state, with relevant contribution of the region covered by the Cerrado biome. Given the threat posed by root-knot nematodes (RKN, Meloidogyne spp.) to coffee production, we collected plant and soil samples from infested plantations across 16 counties and identified the species of this pathogen. Based on the female perineal patterns, male morphology, esterase phenotypes and SCAR markers, the species found were Meloidogyne exigua, Meloidogyne paranaensis, Meloidogyne incognita and Meloidogyne arenaria. The most prevalent species was M. exigua, occurring in 83.8% of the sampled sites, followed by M. paranaensis (19%) and M. incognita (4.9%). Mixed populations of RKN were observed in 7.7% of the sites, with the highest prevalence of M. exigua + M. paranaensis and M. paranaensis + M. incognita, followed by M. exigua + M. incognita. Meloidogyne arenaria was found in one site, in a mixed population with M. paranaensis + M. exigua. Strategies to prevent the spread of these nematodes to non-infested areas are highly recommended, particularly focusing on the most aggressive species such as M. paranaensis and M. incognita. [ABSTRACT FROM AUTHOR]

By regulating carbon uptake and water loss by plants, stomata are not only responsible for productivity but also survival during drought. The timing of the onset of stomatal closure is crucial for preventing excessive water loss during drought, but is poorly explained by plant hydraulics alone and what triggers stomatal closure remains disputed. We investigated whether the hormone abscisic acid (ABA) was this trigger in a highly embolism‐resistant tree species Umbellularia californica. We tracked leaf ABA levels, determined the leaf water potential and gravimetric soil water content (gSWC) thresholds for stomatal closure and transpiration decline during a progressive drought. We found that U. californica plants have a peaking‐type ABA dynamic, where ABA levels rise early in drought and then decline under prolonged drought conditions. The early increase in ABA levels correlated with the closing of stomata and reduced transpiration. Furthermore, we found that transpiration declined before any large decreases in predawn plant water status and could best be explained by transient drops in midday water potentials triggering increased ABA levels. Our results indicate that ABA‐mediated stomatal regulation may be an integral mechanism for reducing transpiration during drought before major drops in bulk soil and plant water status. Summary statement: The mechanism that initiates stomatal closure during drought is not fully understood. We find that an increase in abscisic acid levels in leaves triggers the onset of stomatal closure during drought. [ABSTRACT FROM AUTHOR]

Introduction: Grazing management is essential to maintain the stability of grassland ecosystems. Methods: To determine the optimal rest-grazing period of alpine meadow, five rest-grazing periods were set based on soil thawing and plant re-greening in this study. The niche, interspecific relationships, and stability of plant communities at different rest-grazing periods were investigated. Results: Rest-grazing during soil thawing resulted in a small niche width and niche overlap of plants, overall positive interspecific associations, and a high stability of plant communities. Delayed rest-grazing time to plant re-greening resulted in a large niche width and niche overlap of plants, overall negative interspecific associations, and a low stability of plant communities. Discussion: Rest-grazing in alpine meadows should begin as soon as possible to promote healthy and sustainable utilization of grasslands. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination in agricultural soils and its accumulation in plant organs have become a global issue due to its harmful effects on human health. The in-situ stabilizing technique, which involves using organic amendments, is commonly employed for removing Cd from agricultural soils. Thus, the current study investigated the effect of vermicompost (VC) on soil properties and plant physio-biochemical attributes, leaf ultrastructure analysis, antioxidant defense mechanisms, and grain yields of two different fragrant rice cultivars, Xiangyaxiangzhan (XGZ) and Meixiangzhan-2 (MXZ-2), under Cdstress conditions. The results showed that Cd toxicity deteriorates soil quality, the plant's photosynthetic apparatus, and the plant's antioxidant defense mechanism. Moreover, under Cd stress, both cultivars produced significantly lower (p < 0.05) rice grain yields compared to non-Cd stress conditions. However, the VC application alleviated the Cd toxicity and improved soil qualitative traits, such as soil organic carbon, available nitrogen, total nitrogen, phosphorus, and potassium. Similarly, VC amendments improved leaf physiological activity, photosynthetic apparatus function, antioxidant enzyme activities and its related gene expression under Cd stress These enhancements led to increased grain yields of both fragrant under Cd toxicity. The addition of VC mitigated the adverse effects of Cd on the leaf chloroplast structure by reducing Cd uptake and accumulation in tissues. This helped prevent Cd-induced peroxidation damage to leaf membrane lipids by increasing the activities of antioxidant enzymes such as ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD). On average across the growth stages, the Pos-Cd + VC3 treatment increased SOD, APX, CAT, and POD activities by122.2 and 112.5%, 118.6, and 120.6%, 44.6 and 40.6%, and 38.6 and 33.2% in MXZ-2 and XGZ, respectively, compared to the plants treated with Pos-Cd treated alone. Enhancements in leaf physiological activity and plant antioxidant enzyme activity strengthen the plant's antioxidant defense mechanism against Cd toxicity. In addition, correlation analysis showed a strong relationship between the leaf net photosynthetic rate and soil chemical attributes, suggesting that improved soil fertility enhances leaf physiological activity and boosts rice grain yields. Of the treatments, Pos-Cd + VC3 proved to be the most effective treatment in terms of enhancing soil health and achieving high fragrant rice yields. Thus, the outcomes of this study show that the addition of VC in Cd-contaminated soils could be useful for sustainable rice production and safe utilization of Cdpolluted soil. [ABSTRACT FROM AUTHOR]

Grasslands are integral to maintaining biodiversity and key ecosystem services and are under threat from climate change. Plant and soil microbial diversity, and their interactions, support the provision of multiple ecosystem functions (multifunctionality). However, it remains virtually unknown whether plant and soil microbial diversity explain a unique portion of total variation or shared contributions to supporting multifunctionality across global grasslands. Here, we combine results from a global survey of 101 grasslands with a novel microcosm study, controlling for both plant and soil microbial diversity to identify their individual and interactive contribution to support multifunctionality under aridity and experimental drought. We found that plant and soil microbial diversity independently predict a unique portion of total variation in above- and belowground functioning, suggesting that both types of biodiversity complement each other. Interactions between plant and soil microbial diversity positively impacted multifunctionality including primary production and nutrient storage. Our findings were also climate context dependent, since soil fungal diversity was positively associated with multifunctionality in less arid regions, while plant diversity was strongly and positively linked to multifunctionality in more arid regions. Our results highlight the need to conserve both above- and belowground diversity to sustain grassland multifunctionality in a drier world and indicate climate change may shift the relative contribution of plant and soil biodiversity to multifunctionality across global grasslands. Grasslands are integral to maintaining biodiversity and key ecosystem services under climate change. This study combines a global survey of 101 grasslands with a novel microcosm experiment to show that plant and soil microbial diversity independently predict a unique portion of variation in above- and below-ground functioning. [ABSTRACT FROM AUTHOR]