Reduction In Biomass Research Articles

Assessing consumers' preferences for beef and lamb meat linked to wildfire prevention services

Meat from silvopastoral systems, due to its provision of numerous ecosystem services such as wildfire risk reduction in Mediterranean forests, can address societal growing demands for meat produced with lower environmental impacts. Differentiation of meat from these systems may contribute to their economic sustainability and hence to reverse their decline in the Mediterranean. This study investigated consumer preferences and willingness-to-pay (WTP) for beef and lamb meat from silvopastoral systems associated to the provision of wildfire prevention service and explored two alternative ways of labelling this service. Through a choice experiment survey considering type of pasture, length of grazing period, production distance and price, we gathered data from 1209 meat consumers in two Spanish cities. We considered forest grazing with a target purpose as a level in the type of pasture attribute and it was presented either as grazing to prevent wildfires or grazing to reduce biomass in two alternative versions of the valuation survey. The random parameter logit model revealed the highest preferences and WTP towards nearby production distances, followed by targeted grazing and forest grazing, while the length of grazing period was less relevant. No significant differences in consumers WTP were found between conveying targeted grazing either as fire prevention or biomass reduction. Our findings also suggest that consumers' preferences varied with location, attitudes towards local food and environmental role of grazing and consumption habits. Knowledge gathered in our work contributes to understand consumers perceptions on the beneficial environmental impacts of meat production.

Herbicide response and germination behavior of two goosegrass (Eleusine indica) populations in the Australian environment

AbstractGoosegrass [Eleusine indica (L.) Gaertn.] is one of the most problematic grassy weeds in the world. It is considered to be an important weed in summer fallows and crops grown in the eastern region of Australia. To examine the seed germination ecology of two populations (Gatton and Ingham) of E. indica and their response to postemergence herbicides in Australian conditions, experiments were carried out in the laboratory and screenhouse. Seedling survival, spike production, and plant biomass of both E. indica populations declined markedly with the application of postemergence herbicides such as butroxydim, clethodim, glufosinate, haloxyfop, and propaquizafop, whereas the application of paraquat failed to control the Ingham population. A dose–response study verified the presence of paraquat resistance in the Ingham population. In this regard, it was observed that the paraquat doses required to achieve a 50% reduction in survival and plant biomass were 27 and 21 times greater in the Ingham population compared to the Gatton population, respectively. Higher alternating temperatures (35/25 and 30/20 C) resulted in greater germination of both populations than lower alternating temperatures (20/10 and 25/15 C). At 20/10 C, the Ingham population failed to germinate; however, about 15% germination in the Gatton population was observed. At the lowest alternate temperature range (15/5 C), neither population germinated. The germination of both populations of E. indica was severely reduced under completely dark conditions compared with the alternating light/dark period. Germination was more tolerant of salt and water stress in the Ingham population compared with the Gatton population. Eleusine indica seedling emergence was comparable among populations, and the greatest emergence (83%) was observed for seeds buried at a depth of 2 cm but then declined dramatically, and no seedlings emerged from an 8-cm burial depth. The information acquired from this study could be used in developing effective management strategies for E. indica.

Vapour pressure deficit modulates hydraulic function and structure of tropical rainforests under nonlimiting soil water supply.

Atmospheric conditions are expected to become warmer and drier in the future, but little is known about how evaporative demand influences forest structure and function independently from soil moisture availability, and how fast-response variables (such as canopy water potential and stomatal conductance) may mediate longer-term changes in forest structure and function in response to climate change. We used two tropical rainforest sites with different temperatures and vapour pressure deficits (VPD), but nonlimiting soil water supply, to assess the impact of evaporative demand on ecophysiological function and forest structure. Common species between sites allowed us to test the extent to which species composition, relative abundance and intraspecific variability contributed to site-level differences. The highest VPD site had lower midday canopy water potentials, canopy conductance (gc ), annual transpiration, forest stature, and biomass, while the transpiration rate was less sensitive to changes in VPD; it also had different height-diameter allometry (accounting for 51% of the difference in biomass between sites) and higher plot-level wood density. Our findings suggest that increases in VPD, even in the absence of soil water limitation, influence fast-response variables, such as canopy water potentials and gc , potentially leading to longer-term changes in forest stature resulting in reductions in biomass.

In vitro establishment of cell suspension culture of Ceropegia bulbosa for improved production of cerpegin content through elicitation of engineered carbon and ZnO nanoparticles.

The present investigations aimed to conserve C. bulbosa a threatened plant species and for production of cerpegin through cell culture technology using ENP elicitation. Leaf explants were aseptically cultured with normal MS medium-supplemented PGRs BA and NAA various concentrations, and the best callus induction response was recorded on 4.5 + 4.5 μM. The prospective special effects of the ENPs on plant cell cultures are the key part of our study and used to evaluate leaf callus culture proliferation with the reduction of browning, establishment, biomass, and metabolite formation. The CNP concentrations (0, 2, 4, 8, 12 mg/l) are used for the callus proliferation and browning reduction. The cell suspension cultures are also established, and they were elicited with EZnONPs (0, 25, 50, 100, 150 mg/l) for evaluation of biomass, antioxidant, non-antioxidant enzyme activation, toxicity, ROS defense activation, and metabolite development in cell cultures. The metabolite extraction, UV, and NMR characterization confirm that the toxic and nontoxic effect of ENPs on leaf cell cultures varies with high to low concentration.

Mutation of putative glycosyl transferases PslC and PslI confers susceptibility to antibiotics and leads to drastic reduction in biofilm formation in Pseudomonas aeruginosa.

Pseudomonas aeruginosa is an opportunistic, multidrug-resistant pathogen capable of adapting to numerous environmental conditions and causing fatal infections in immunocompromised patients. The predominant lifestyle of P. aeruginosa is in the form of biofilms, which are structured communities of bacteria encapsulated in a matrix containing exopolysaccharides, extracellular DNA (eDNA) and proteins. The matrix is impervious to antibiotics, rendering the bacteria tolerant to antimicrobials. P. aeruginosa also produces a plethora of virulence factors such as pyocyanin, rhamnolipids and lipopolysaccharides among others. In this study we present the molecular characterization of pslC and pslI genes, of the exopolysaccharide operon, that code for putative glycosyltransferases. PslC is a 303 amino acid containing putative GT2 glycosyltrasferase, whereas PslI is a 367 aa long protein, possibly functioning as a GT4 glycosyltransferase. Mutation in either of these two genes results in a significant reduction in biofilm biomass with concomitant decline in c-di-GMP levels in the bacterial cells. Moreover, mutation in pslC and pslI dramatically increased susceptibility of P. aeruginosa to tobramycin, colistin and ciprofloxacin. Additionally, these mutations also resulted in an increase in rhamnolipids and pyocyanin formation. We demonstrate that elevated rhamnolipids promote a swarming phenotype in the mutant strains. Together these results highlight the importance of PslC and PslI in the biogenesis of biofilms and their potential as targets for increased antibiotic susceptibility and biofilm inhibition.

Influences of lithium on soil microbial biomass, bacterial community structure, diversity, and function potential

Lithium is an emerging contaminant, but there is little knowledge about its influences on soil microbial ecosystem. In this work, soils were treated with 10 to 1280 mg/kg lithium (Li10 to Li1280), and then microbial biomass assay and bacterial 16S rRNA high-throughput sequencing analysis were conducted to investigate the influences of lithium on soil microbial biomass, bacterial community structure and diversity, and predicted function potential. The results showed that lithium generally decreased microbial biomass carbon and the count of culturable microbe colony, reflecting the reduction in microbial biomass. However, microbial biomass nitrogen increased. Meanwhile, lithium altered bacterial community composition, structure, and dominance. The abundance of phylum such as Proteobacteria and Acidobacteria respectively increased and reduced under lithium stress, while genus such as Adhaeribacter dominated in control group to Li320, and genus such as Lysobacter dominated in Li640, Li960, and Li1280. Then, higher lithium treatments consistently inhibited the bacterial richness, evenness, and diversity, and caused community dissimilarity between groups and significant down-regulation of predicted pathways. Finally, the LEfSe cladogram distinguished several indicator bacteria for different lithium levels. Overall, the influences of lithium on soil microbial community depended on its content, and microbial biomass and richness were sensitive to lower lithium, while higher lithium varied bacterial community and predicted function potential more significantly. This study will provide microbial insights into understanding lithium contamination.

In Vitro Impact of Fluconazole on Oral Microbial Communities, Bacterial Growth, and Biofilm Formation.

Antifungal agents are widely used to specifically eliminate infections by fungal pathogens. However, the specificity of antifungal agents has been challenged by a few studies demonstrating antibacterial inhibitory effects against Mycobacteria and Streptomyces species. Here, we evaluated for the first time the potential effect of fluconazole, the most clinically used antifungal agent, on a human oral microbiota biofilm model. The results showed that biofilm viability on blood and mitis salivarius agar media was increased over time in the presence of fluconazole at clinically relevant concentrations, despite a reduction in biomass. Targeted PCR revealed a higher abundance of Veillonella atypica, Veillonella dispar, and Lactobacillus spp. in the fluconazole-treated samples compared to the control, while Fusobacterium nucleatum was reduced and Streptococcus spp were not significantly affected. Further, we tested the potential impact of fluconazole using single-species models. Our results, using Streptococcus mutans and Streptococcus mitis luciferase reporters, showed that S. mutans planktonic growth was not significantly affected by fluconazole, whereas for S. mitis, planktonic growth, but not biofilm viability, was inhibited at the highest concentration. Fluconazole's effects on S. mitis biofilm biomass were concentration and time dependent. Exposure for 48 h to the highest concentration of fluconazole was associated with S. mitis biofilms with the most increased biomass. Potential growth inhibitory effects were further tested using four non-streptococcal species. Among these, the planktonic growth of both Escherichia coli and Granulicatella adiacens was inhibited by fluconazole. The data indicate bacterial responses to fluconazole that extend to a broader range of bacterial species than previously anticipated from the literature, with the potential to disturb biofilm communities.

Nitrogen addition enhances tree radial growth but weakens its recovery from drought impact in a temperate forest in northern China

Forest growth in the majority of northern China is currently limited by drought and low nitrogen (N) availability. Drought events with increasing intensity have threatened multiple ecosystem services provided by forests. Whether N addition will have a detrimental or beneficial moderation effect on forest resistance and recovery to drought events was unclear. Here, our study focuses on Pinus tabulaeformis, which is the main plantation forest species in northern China. We investigated the role of climate change and N addition in driving multi-year tree growth with an 8-year soil nitrogen fertilization experiment and analyzing 184 tree ring series. A moderate drought event occurred during the experiment, providing an opportunity for us to explore the effects of drought and N addition on tree resistance and recovery. We found that N addition was beneficial for increasing the resistance of middle-aged trees, but had no effect on mature trees. The recovery of trees weakened significantly with increasing N addition, and the reduction in fine root biomass caused by multiyear N addition was a key influencing factor limiting recovery after moderate drought. Our study implies that the combined effect of increasing drought and N deposition might increase the risk of pine forest mortality in northern China.

Decadal increase in vessel interactions by a scavenging pelagic seabird across the North Atlantic

Fisheries waste is used by many seabirds as a supplementary source of food,1 but interacting with fishing vessels to obtain this resource puts birds at risk of entanglement in fishing gear and mortality.2 As a result, bycatch is one of the leading contributors to seabird decline worldwide,3 and this risk may increase over time as birds increasingly associate fishing vessels with food. Light-level geolocators mounted on seabirds can detect light emitted from vessels at night year-round.4 We used a 16-year time series of geolocator data from 296 northern fulmars (Fulmarus glacialis) breeding at temperate and arctic colonies to investigate trends of nocturnal vessel interactions in this scavenging pelagic seabird. Vessel attendance has progressively increased over the study period despite no corresponding increase in the number of vessels or availability of discards over the same time frame. Fulmars are highly mobile generalist surface feeders,5 so this may signal a reduction in available prey biomass in the upper water column, leading to increased reliance on anthropogenic food subsidies6 and increased risk of bycatch mortality in already threatened seabird populations. Individuals were consistent in the extent to which they interacted with vessels, as shown in other species,7 suggesting that population-level increases may be due to a higher proportion of fulmars following vessels rather than changes at an individual level. Higher encounter rates were correlated with lower time spent foraging and a geographically restricted overwintering distribution, suggesting an energetic advantage for these scavenging strategists compared with foraging for natural prey.

A Novel Injectable Piezoelectric Hydrogel for Periodontal Disease Treatment.

Periodontal disease is a multifactorial, bacterially induced inflammatory condition characterized by the progressive destruction of periodontal tissues. The successful nonsurgical treatment of periodontitis requires multifunctional technologies offering antibacterial therapies and promotion of bone regeneration simultaneously. For the first time, in this study, an injectable piezoelectric hydrogel (PiezoGEL) was developed after combining gelatin methacryloyl (GelMA) with biocompatible piezoelectric fillers of barium titanate (BTO) that produce electrical charges when stimulated by biomechanical vibrations (e.g., mastication, movements). We harnessed the benefits of hydrogels (injectable, light curable, conforms to pocket spaces, biocompatible) with the bioactive effects of piezoelectric charges. A thorough biomaterial characterization confirmed piezoelectric fillers' successful integration with the hydrogel, photopolymerizability, injectability for clinical use, and electrical charge generation to enable bioactive effects (antibacterial and bone tissue regeneration). PiezoGEL showed significant reductions in pathogenic biofilm biomass (∼41%), metabolic activity (∼75%), and the number of viable cells (∼2-3 log) compared to hydrogels without BTO fillers in vitro. Molecular analysis related the antibacterial effects to be associated with reduced cell adhesion (downregulation of porP and fimA) and increased oxidative stress (upregulation of oxyR) genes. Moreover, PiezoGEL significantly enhanced bone marrow stem cell (BMSC) viability and osteogenic differentiation by upregulating RUNX2, COL1A1, and ALP. In vivo, PiezoGEL effectively reduced periodontal inflammation and increased bone tissue regeneration compared to control groups in a mice model. Findings from this study suggest PiezoGEL to be a promising and novel therapeutic candidate for the treatment of periodontal disease nonsurgically.

Ecological implications of fish removal: Insights from gut-content analysis of roach (Rutilus rutilus) and European perch (Perca fluviatilis) in a eutrophic shallow lake.

Large reductions in fish biomass are common both as a method of managing lake ecosystems by fish removals (biomanipulation) and as naturally occurring fish kills. To further understand how fish reductions change feeding patterns of fish, we studied the diets of small- to medium-sized roach (Rutilus rutilus) and European perch (Perca fluviatilis) on a monthly basis using gut-content analysis during an 18-month period before and after a whole-lake fish removal in a eutrophic shallow lake. Further, we performed in-depth analyses of zoobenthos communities of the profundal and littoral zones, as well as analysed the zooplankton community in the littoral and pelagic parts of the lake to estimate abundance and biomass of potential diet items. We found that, in general, there was a trend toward increased zoobenthivory in both species and among all-sized fish after fish removal, regardless of prior diet preference. Reduced piscivory among larger perch (>150 mm) and reduced zooplanktivory among smaller perch and roach (<150 mm) were also observed. Moreover, during a short period of high zooplankton biomass after fish removal, both perch and roach (all sizes) shifted their diet toward daphnids, which likely caused a decrease in daphnid population. We suggest that such change toward periodical zooplanktivory across fish species and size groups may lead to unexpectedly high top-down control by fish after lake restoration by fish removal.

Responce of European Wheat to Weed Competitiveness as Affected by Potassium Fertilizer Levels

Purpose: The significance of potassium has been well documented as one of the major macronutrients for many crops, particularly wheat. Herbicide resistance in weeds and other environmental issues in the wheat crop has encouraged researchers to find alternative methods for weed management.Research methods: A field experiment was conducted during the winter season 2021-2022 at a private farm in North Samawah city, Iraq to examine the competitive ability of two European wheat cultivars against weeds as affected by potassium (K) levels. Treatments included two wheat cultivars (Milano and Pick-row), and three K fertiliser levels (0, 200 and 400 Kg K2O/ha).Findings: The results showed that Pick-row was a superior cultivar in terms of crop competitive ability with weeds compared with Milano. Pick-row was taller, produced the largest number of spikes, had the greatest grain yield, greatest crop biomass and least weed biomass about 61.5 cm, 70 spike/m2, 0.66 t/ha, 2.29 t/ha, and 52.5 g/m2 respectively. The increased K fertiliser level has a positive effect on crop production and weed biomass reduction, especially with Pick-row cultivar.Originality/ Value: It is implicated that Pick-row can be useful as a competitive cultivar under Al-Muthanna Province environments. Potassium K fertiliser is better to be increased and split into a number of equal doses and applied at different growth stages of wheat to avoid critical competitive timing risks.

Soil Contamination with Europium Induces Reduced Oxidative Damage in Hordeum vulgare Grown in a CO2-Enriched Environment.

The extensive and uncontrolled utilization of rare earth elements, like europium (Eu), could lead to their accumulation in soils and biota. Herein, we investigated the impact of Eu on the growth, photosynthesis, and redox homeostasis in barley and how that could be affected by the future CO2 climate (eCO2). The plants were exposed to 1.09 mmol Eu3+/kg soil under either ambient CO2 (420 ppm, aCO2) or eCO2 (620 ppm). The soil application of Eu induced its accumulation in the plant shoots and caused significant reductions in biomass- and photosynthesis-related parameters, i.e., chlorophyll content, photochemical efficiency of PSII, Rubisco activity, and photosynthesis rate. Further, Eu induced oxidative stress as indicated by higher levels of H2O2 and lipid peroxidation products, and lower ASC/DHA and GSH/GSSG ratios. Interestingly, the co-application of eCO2 significantly reduced the accumulation of Eu in plant tissues. Elevated CO2 reduced the Eu-induced oxidative damage by supporting the antioxidant defense mechanisms, i.e., ROS-scavenging molecules (carotenoids, flavonoids, and polyphenols), enzymes (CAT and peroxidases), and ASC-GSH recycling enzymes (MDHAR and GR). Further, eCO2 improved the metal detoxification capacity by upregulating GST activity. Overall, these results provide the first comprehensive report for Eu-induced oxidative phytotoxicity and how this could be mitigated by eCO2.

Quorum‐sensing in Acetobacter pasteurianus and its effect on acetic acid fermentation

AbstractQuorum‐sensing (QS) is an essential mechanism of microbial self‐regulation. In this work, the presence of QS in Acetobacter pasteurianus was demonstrated, and N‐acyl‐homoserine lactones N‐C4‐HSL and N‐C8‐HSL were identified as the signal molecules. The exogenous addition of N‐C4‐HSL, N‐C8‐HSL, N‐C10‐HSL, and N‐C12‐HSL result in the reduction in biomass, and lead to 11.56%, 11.91%, 7.94%, and 4.69% decrease in acetic acid production, respectively, when compared with the control. A hypothetical N‐acylhomoserine lactonase (AHL lactonase) 0046 was overexpressed in A. pasteurianus CGMCC 3089, and the recombinant strain exhibites a 17.38% and 12.75% increase in the biomass and the acetic acid production rate, respectively. Those results prove the negative regulation of QS on acetic acid fermentation, and overexpression of 0046 protein alleviates this negative effect.

Recurrent forest fires, emission of atmospheric pollutants (GHGs) and degradation of tropical dry deciduous forest ecosystem services

Forest fires threaten to biodiversity, ecosystem productivity, multiple ecosystem services, and it influences the emissions of large amounts of greenhouse gases into the atmosphere. This scientific study has been conducted at Ayodhya hill range of dry deciduous forest of Chota Nagpur plateau (India).The principal objectives of this research are (1) to measure the terrestrial ecosystem productivity by Vegetation Photosynthesis Model (VPM); (2) to estimate the greenhouse gases (GHGs) emission through forest fire following IPCC guidelines; and (3) to quantify the ecosystem service value and degradation of ecosystem services (ESs) by specific indices and focus group discussions (FGDs). Results show that biophysical, climatic and environmental factors notably affect the growth of ESs. A significant reduction of net primary production (NPP) and biomass has been measured in fire month (100.71 and 223.59 gC m−2 month−1) and values of spectral indices also show negative trend during fire month (-0.1279 to −0.2104) respectively. Total 294.15 g, 1.44 g, 21.03 g, 0.0099 g and 0.0231 g of CO2, CH4, CO, NO2, and NOX have been emitted respectively through forest fire from this hill range during forest burning period (March 2021). This study also revealed that average (18.50%) forest dependency or relative forest income (RFI) has been fallen in the recent years due to recurrent forest fires, execution of different developmental works and deforestation. The effective management of forest resources (through payment for ESs and willingness to pay approaches) is highly necessary in strengthening the rural economy and welfare of indigenous tribal people.

VULNERABILITY OH FISHES CAUGHT BY TRAP FISHING IN NORTHEASTERN – BRAZIL

In Northeastern Brazil, the trap fishing occurs mainly in rocky bottoms and a high diversity of fishes is caught. These characteristics, associated with the growing fishing effort, threat the maintenance of the biodiversity of these environments, since this fishing is not monitored, as a result of the deficiency in public management in monitoring small-scale fishing and in promoting research projects aimed at this objective. Due to the lack of detailed information on trap fisheries, this exploitation is prone to be assessed for impacts using semi-quantitative methods, built for data-poor situations. Our objective was to estimate the degree of vulnerability to trap fishing for the captured species through productivity-susceptibility analysis (PSA), based on data observed during fisheries monitoring and data obtained from the literature. Thus, it was possible to generate the necessary information to assist in the elaboration of management policies for this fishery in Northeastern Brazil. The Haemulidae family was the most abundant among the captured individuals, with Haemulon aurolineatum representing 29.7% of the sample. The PSA indicated that, although all species have high productivity, Pseudopeneus maculatus, Lutjanus synagris and Haemulon plumierii were the most vulnerable species, respectively. Furthermore, from 2000 to 2010 the trap fishing was directed to the P. maculatus; however, we verified a change in the target species, due to the biomass reduction of P. maculatus in the area. Therefore, it seems necessary to reassess this species building a management plan since they were classified by IUCN Red List as Least Concern – LC and according to results of the current study may not be the case anymore. Keywords: Data-Poor; Fishing effort; Spotted goatfish

Integrating surfactants with low enzyme loading to increase the glucan conversion and ethanol concentration of reed after combined pretreatment

In this study, in order to obtain high concentration bioethanol, reed pretreated with liquid hot water and ammonia oxygen (LHW-NH3·H2O/O2) was used as the substrate for fermentation. Enzymatic hydrolysis becomes difficult by the ineffective lignin adsorption and the decline in cellulase activity. It is worth noting that even under low enzyme loading (9 FPU/g pretreated solid), this study was able to maintain a higher glucan conversion rate (97.60%). In addition, under high solid loading conditions, the combined effect of PEG 6000 and rhamnolipids increased ethanol yield (78.40%) and ethanol concentration (71.5 g/L). The combined LHW-NH3·H2O/O2 pretreatment with fed-batch semi-simultaneous saccharification and fermentation technique may be utilized to industrialize the production of bioethanol from reed since we concentrated on the maximum exploitation of biomass resources and reduction in energy consumption.

Application of magnesium and biosurfactant functionalized biochar composite in treating cyanobacteria in phosphorus and crude oil contaminated water

Various human activities have led to multiple contamination of natural water systems. The present study investigated the effect of a novel multifunctional biochar to treat nutrients, oil, and harmful algae in water. Specifically, magnesium (Mg) and biosurfactant rhamnolipid (RL) were incorporated into biochar, including Mg-biochar, RL-biochar, and Mg-RL-biochar. Their adsorption efficiency on phosphate and total petroleum hydrocarbons (TPH) was evaluated in separate batch studies. Also, the inhibition effect of RL-modified biochars on cyanobacteria was investigated. The results showed that Mg-impregnated biochar showed high adsorption capacity on phosphate (118 mg g−1), while RL-modified biochar significantly reduced TPH (especially aromatic and light aliphatic fraction) with adsorption capacity of 44.4 mg g−1. The inhibition effects of biochar composites on algae in water without contaminants were in order of Mg-RL-biochar > RL-biochar > biochar with biomass reduction ranging 61–64%. Overall, Mg-RL-biochar was suggested based on this study due to its ability to remove PO43− and TPH, and inhibit the growth of toxic algae.Graphical abstract

Tumble windmill grass (Chloris verticillata Nutt.) control with POST herbicides

AbstractTumble windmill grass (Chloris verticillata Nutt.) is a problematic perennial grass weed in the semiarid Central Great Plains (CGP). Greenhouse and fallow field experiments were conducted during 2021 and 2022 at Kansas State University Agricultural Research Center near Hays, KS, to determine the effectiveness of various POST herbicides for tumble windmill grass control. All selected POST herbicides were applied at field‐recommended rates at the seedling growth stage (3‐to 4‐inches tall) of tumble windmill grass in greenhouse study. Tumble windmill grass was at the heading growth stage (10‐to‐12‐inches tall) in fallow fields when POST herbicides were tested. Results from greenhouse study indicated that quizalofop‐P‐ethyl (QPE) and clethodim provided ≥ 95% control and shoot biomass reduction of tumble windmill grass at 28 days after treatment. Glyphosate provided 89% control and 93% shoot biomass reduction of tumble windmill grass. Imazamox and nicosulfuron had the least control (41 to 51%) and shoot biomass reduction (43 to 66%) of tumble windmill grass in greenhouse study. In contrast, all tested POST herbicides were comparatively less effective on tumble windmill grass (≤68% control and ≤ 50% shoot biomass reduction) except glyphosate (85% control and 54% shoot biomass reduction) in field study. These results conclude that clethodim, QPE, and glyphosate applied at early growth stages can provide effective control of tumble windmill grass in the CGP region.

Influence of nanoscale sulfur on mercury accumulation and plant growth in oilseed rape seedlings (Brassica napus L.) grown on mercury-contaminated soil

Mercury (Hg) pollution has seriously threatened the crop productivity and food security. In the present research, experiments were conducted to assess the influence of nanoscale sulfur/sulfur nanoparticles and the corresponding bulk and ionic sulfur forms on the growth and Hg accumulation of oilseed rape seedlings grown on Hg-contaminated soil, as well as the transformation of soil Hg fractions. The results showed a significant reduction in fresh biomass for seedlings grown on 80–200 mg/kg Hg-polluted soil after 30 days. At 120 mg/kg Hg treatment, 100–300 mg/kg sulfur nanoparticles (SNPs) application counteracted Hg toxicity more effectively compared to the corresponding bulk sulfur particles (BSPs) and ionic sulfur (sulfate) treatments. The seedlings treated with 120 mg/kg Hg + 300 mg/kg SNPs gained 54.2 and 56.9% more shoot and root biomass, respectively, compared to those treated with Hg alone. Meanwhile, 300 mg/kg SNPs application decreased Hg accumulation by 18.9 and 76.5% in shoots and roots, respectively, relative to Hg alone treatment. SNPs treatment caused more Hg to be blocked in the soil and accumulating significantly less Hg in plants as compared to other S forms. The chemical fractions of Hg in the soil were subsequently investigated, and the solubility of Hg was significantly decreased by applying SNPs to the soil. Especially 200–300 mg/kg SNPs treatments caused the ratio of the soluble/exchangeable and the specifically absorbed fraction to be the lowest, accounting for 1.95–4.13% of the total Hg of soil. These findings suggest that adding SNPs to Hg-contaminated soils could be an effective measure for immobilizing soluble Hg and decreasing the Hg concentration in the edible parts of crops. The results of the current study hold promise for the practical application of SNPs to Hg-contaminated farmland for better yields and simultaneously increasing the food safety.