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The maintenance of biological diversity is frequently enhanced in a heterogenous landscape by some level of disturbance. Thus, when a landscape becomes stabilized and homogenized through the spread of an invasive plant species, there may be consequences for native biodiversity, particularly for those biotas that depend on the pre‐existing, natural disturbance regime of that landscape. At Long Point, Ontario, Canada, a sandspit in Lake Erie, the community of anuran amphibians experienced the co‐incidence of 2 major disturbance events, 1 anthropogenic and 1 natural: an intervention to remove the invasive form of the common reed (Phragmites australis australis) and a spate of extensive dune washouts caused by high water levels and storms. As a result of the unequal distribution of disturbance in the landscape, different areas were affected by only the dune washouts, only the common reed treatment, both disturbances, or neither disturbance. From May to August 2021, we explored how the disturbances affected the resident frog and toad species habitat associations in the 4 different disturbance conditions in the landscape. By means of minnow traps, acoustic surveys, and visual surveys, we determined that the dune washouts had a greater influence on resident anurans than the common reed treatment. Ranid frogs (Ranidae) tended to inhabit non‐washout sites, whereas Fowler's toads (Anaxyrus fowleri) congregated in the newly formed, sand flats and shallow, de‐vegetated pools resulting from the washouts. Neither ranid frogs nor Fowler's toads demonstrated avoidance of the sites affected by the herbicide treatment and mechanical rollover of the common reed. This evidence of species sorting, which enables multiple species to persist in a dynamic and heterogeneous landscape, suggests that wildlife management in aid of threatened species recovery may find success by encouraging natural disturbance regimes in dynamic landscapes. Future management endeavors should consider refraining from complete dune stabilization in these landscapes to allow the natural washouts to occur at a higher frequency, while ensuring the continued effectiveness of the invasive common reed eradication. [ABSTRACT FROM AUTHOR]

Background: The prevalence of metabolic syndrome (MetS) in American adults increased from 37.6% in the 2011–12 period to 41.8% in 2017–2018. Environmental exposure, particularly to common compounds such as glyphosate, has drawn increasing attention as a potential risk factor. Methods: We employed three cycles of data (2013–2018) from the National Health and Nutrition Examination Survey (NHANES) in a cross-sectional study to examine potential associations between urine glyphosate measurements and MetS incidence. We first created a MetS score using exploratory factor analysis (EFA) of the International Diabetes Federation (IDF) criteria for MetS, with data drawn from the 2013–2018 NHANES cycles, and validated this score independently on an additional associated metric, the albumin-to-creatinine (ACR) ratio. The score was validated via a machine learning approach in predicting the ACR score via binary classification and then used in multivariable regression to test the association between quartile-categorized glyphosate exposure and the MetS score. Results: In adjusted multivariable regressions, regressions between quartile-categorized glyphosate exposure and MetS score showed a significant inverted U-shaped or saturating dose‒response profile, often with the largest effect for exposures in quartile 3. Exploration of potential effect modification by sex, race, and age category revealed significant differences by race and age, with older people (aged > 65 years) and non-Hispanic African American participants showing larger effect sizes for all exposure quartiles. Conclusions: We found that urinary glyphosate concentration is significantly associated with a statistical score designed to predict MetS status and that dose–response coefficient is nonlinear, with advanced age and non-Hispanic African American, Mexican American and other Hispanic participants exhibiting greater effect sizes. [ABSTRACT FROM AUTHOR]

Summary: Microbial communities can rapidly respond to stress, meaning plants may encounter altered soil microbial communities in stressful environments. These altered microbial communities may then affect natural selection on plants. Because stress can cause lasting changes to microbial communities, microbes may also cause legacy effects on plant selection that persist even after the stress ceases.To explore how microbial responses to stress and persistent microbial legacy effects of stress affect natural selection, we grew Chamaecrista fasciculata plants in stressful (salt, herbicide, or herbivory) or nonstressful conditions with microbes that had experienced each of these environments in the previous generation.Microbial community responses to stress generally counteracted the effects of stress itself on plant selection, thereby weakening the strength of stress as a selective agent. Microbial legacy effects of stress altered plant selection in nonstressful environments, suggesting that stress‐induced changes to microbes may continue to affect selection after stress is lifted.These results suggest that soil microbes may play a cryptic role in plant adaptation to stress, potentially reducing the strength of stress as a selective agent and altering the evolutionary trajectory of plant populations. [ABSTRACT FROM AUTHOR]

Carryover injury caused by premix herbicide Lumax®537.5SE has not been studied. This study documents this event and aims to support or reject the following hypothesis under field conditions: a crop treated with melatonin, a plant hormone, can tolerate herbicide carryover–induced stress. A split-plot design was arranged in a randomized complete block design (RCBD). Main plots were 0, 4, and 6 L ha−1 Lumax®537.5SE applied 11 months before planting. Subplots were non-treated control and melatonin applied at 1 mM in the manners of seed tuber application, single foliar application, single foliar + seed tuber application, double foliar application, and double foliar + seed tuber application. Without Lumax®537.5SE, single foliar application of melatonin increased the yields of marketable No. 1 (20%), unmarketable (34%), and total (15%) tubers compared to control. The double foliar application of melatonin caused a further increase in the yields. The carryover of Lumax®537.5SE injured potato by reducing and cracking its tubers in a dose-dependent manner. Without Lumax®537.5SE, no cracked tuber was harvested, while with 4 and 6 L ha−1, 0.46 and 0.63 kg m−2 tubers were cracked, respectively. The seed tuber application of melatonin did not affect improving potato and mitigating it against Lumax®537.5SE carryover. Other melatonin treatments reduced cracks in the tubers, improving the yields. Quality and quantity loss of tubers caused by Lumax®537.5SE carryover could be mitigated by foliar-applying melatonin twice. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) are formed in plant cells continuously. When ROS production exceeds the antioxidant capacity of the cells, oxidative stress develops which causes damage of cell components and may even lead to the induction of programmed cell death (PCD). The levels of ROS production increase upon abiotic stress, but also during pathogen attack in response to elicitors, and upon application of toxic compounds such as synthetic herbicides or natural phytotoxins. The commercial value of many synthetic herbicides is based on weed death as result of oxidative stress, and for a number of them, the site and the mechanism of ROS production have been characterized. This review summarizes the current knowledge on ROS production in plants subjected to different groups of synthetic herbicides and natural phytotoxins. We suggest that the use of ROS-specific fluorescent probes and of ROS-specific marker genes can provide important information on the mechanism of action of these toxins. Furthermore, we propose that, apart from oxidative damage, elicitation of ROS-induced PCD is emerging as one of the important processes underlying the action of herbicides and phytotoxins. [Display omitted] • The main reactive oxygen species (ROS) formed immediately after application of a phytotoxin indicate its mode of action. • ROS-specific marker genes and fluorescent probes can help to identify the major ROS induced in weeds by phytotoxins. • ROS induced in plants by natural phytotoxins can initiate programmed cell death (PCD). • Future herbicides with reduced toxicity for humans and animals should be based on induction of plant-specific PCD. [ABSTRACT FROM AUTHOR]

Weed control success with pre-emergence (PRE) herbicides is affected by environmental factors including rainfall and plant residue. Two greenhouse experiments were conducted to evaluate PRE herbicide efficacy against johnsongrass [Sorghum halepense (L.) Pers.], prickly sida (Sida spinosa L.) and velvetleaf (Abutilon theophrasti Medik.). One experiment investigated herbicide efficacy under two crop residue amounts (2500 and 5000 kg ha−1) and the second examined herbicide efficacy influenced by simulated rain at two, four, and eight days after application (DAA). Five herbicides (pendimethalin, metribuzin, clomazone, imazethapyr and pyroxasulfone) and four nozzles types (XR, ULD, TTI and TTI60) were used. Nozzle type did not affect weed control across residue levels. Pendimethalin better controlled S. halepense under the low residue level. Imazethapyr efficacy for S. spinosa and A. theophrasti increased under high residue level. Imazethapyr applications for S. spinosa and A. theophrasti control were more effective when sprayed with the TTI nozzle regardless of rainfall timing. Longer periods without rain after application improved pendimethalin efficacy against S. spinosa and A. theophrasti, while pyroxasulfone better controlled S. spinosa with rain two DAA. Metribuzin and clomazone provided the best weed control among herbicides for all residue levels and rainfall scenarios. [ABSTRACT FROM AUTHOR]

A spectral image analysis has the potential to replace traditional approaches for assessing plant responses to different types of stresses, including herbicides, through non-destructive and high-throughput screening (HTS). Therefore, this study was conducted to develop a rapid bioassay method using a multi-well plate and spectral image analysis for the diagnosis of herbicide activity and modes of action. Crabgrass (Digitaria ciliaris), as a model weed, was cultivated in multi-well plates and subsequently treated with six herbicides (paraquat, tiafenacil, penoxsulam, isoxaflutole, glufosinate, and glyphosate) with different modes of action when the crabgrass reached the 1-leaf stage, using only a quarter of the recommended dose. To detect the plant's response to herbicides, plant spectral images were acquired after herbicide treatment using RGB, infrared (IR) thermal, and chlorophyll fluorescence (CF) sensors and analyzed for diagnosing herbicide efficacy and modes of action. A principal component analysis (PCA), using all spectral data, successfully distinguished herbicides and clustered depending on their modes of action. The performed experiments showed that the multi-well plate assay combined with a spectral image analysis can be successfully applied for herbicide bioassays. In addition, the use of spectral image sensors, especially CF images, would facilitate HTS by enabling the rapid observation of herbicide responses at as early as 3 h after herbicide treatment. [ABSTRACT FROM AUTHOR]

Ecologists have explored community assembly through the framework of ecological filters, which predicts that species must overcome a series of challenges (i.e. pass through "filters") to successfully establish in a given community. In the context of restoration, these filters (dispersal, abiotic, and biotic) can be manipulated to alter the resulting plant community by favoring native species or disadvantaging non‐native invasive species. We conducted two studies manipulating assembly filters at two California grassland sites previously dominated by non‐native species. At Site 1, we explored how variations in sequential seeding of native grasses and forbs (to overcome dispersal and biotic filters caused by priority effects) influenced the resulting community. At Site 2, we explored how thatch removal (to overcome the abiotic filter of light limitation) and herbicide‐based weed control (to overcome the biotic filter of competition from non‐native species) influenced the addition of native forbs into a partially restored grassland. Native forbs at Site 1 did not suffer from arriving after grasses, but native grasses benefited when given 1 year priority over forbs. At Site 2, dethatching increased native forb cover in a high rainfall year. Herbicide application reduced non‐native grass cover in dethatched plots without negatively affecting native cover. Native forb and grass cover were significant predictors of non‐native grass cover. However, they accounted for only 29% of the variation observed, suggesting there are other influential factors not considered in this study. Our results suggest that forbs can be incorporated into established native grasslands more successfully after dethatching. [ABSTRACT FROM AUTHOR]

Phytotoxicity refers to the capacity of chemical substances or environmental factors to have a negative impact on plants. This is a crucial issue in both the context of crop cultivation and environmental protection. The research results were based on a 3-year field experiment conducted at an experimental station in Jadwisin (52°28′ N, 21°02′ E) on loamy soil. The experiment was set up using a randomized sub-block design in a split–split–plot arrangement with three replications. The first-order factor consisted of potato cultivars, while the second-order factors were weed control methods: (1) without protection; (2) mechanical weed control, extensive mechanical treatments to close rows; (3) Sencor 70 WG—pre-emergence (PRE) of potatoes; (4) Sencor 70 WG + Titus 25 WG + Trend 90 EC—PRE of potatoes; (5) Sencor 70 WG—post-emergence (POST) of potatoes; (6) Sencor 70 WG + Titus 25 WG + Trend 90 EC—POST of potatoes; (7) Sencor 70 WG + Fusilade Forte 150 EC—POST of potatoes; and (8) Sencor 70 WG + Apyros 75 WG + Atpolan 80 SC—POST of potatoes. The phytotoxic effects of herbicides on potato plants and weeds were assessed every 7 days, starting from the date when the first signs of damage appeared until they stabilized or disappeared. Phytotoxic damage to potato and weed plants was caused by the chemical weed control methods used. The response of potato plants to herbicides was significantly related to the genetic traits of the cultivars and meteorological conditions in the years of research. Phytotoxicity is an important aspect in both agriculture and environmental protection. Research on its mechanisms and impact will enable the development of effective plant protection strategies and the preservation of ecosystem balance. [ABSTRACT FROM AUTHOR]

The biodegradation behavior of pesticides on and in various edible plants was studied by many others. They concluded that the current levels of the pesticides in surface water and plants do not constitute an acute toxicity hazard to man and animals on a short-term basis, but as a result of their accumulation in the main body, it causes a hazard of long-term exposure. Visual observation by light and electron microscopes of four Streptomyces spp. isolated from rhizosphere potato plants showed differentiation in mycelium and conidia spores as well as a variable diffusible pigment in a selective medium. The four Streptomyces spp. were identified as Streptomyces scabies by VITEK 2 system. The potential of granola herbicide degradation in relation to S. scabies isolates detected by polymerase chain reaction (PCR). Four S. scabies isolates showed different potential abilities to degrade the gramonol in Lab. and in soil in the course of 5 days of incubation and 35 days post herbicide treatment respectively. It is clear that S. scabies isolates St4 was more active in gramonol degradation than the other isolates. Dehalogenase gene was detected by PCR in DNA genome of 4 isolates. It was found differences among isolates related to fragment density and size. Residual gramonol determined by GLC after 10, 20 and 30 days. It was observed the degradation rate increased with increased time as well as a small amount of gramonol residue was observed in non-sterilized soil compared with sterilized soil in relation to increasing the count of total microorganisms. On the other hand, the effect of gramonol on Streptomyces isolates growth was non-observed. [ABSTRACT FROM AUTHOR]

African lovegrass (Eragrostis curvula Schrad. Nees, Poaceae) is an introduced pasture species which provides little grazing or nutritional value for livestock under the prevailing conditions in Australia. Current management options, which include herbicides, strategic grazing of new growth, species replacement and fertiliser application have not been effective at providing sustained reductions in African lovegrass cover. Therefore, biological control (biocontrol) of African lovegrass is now being considered as a potential management tool in Australia. An important initial step in this exploration is to understand community views about African lovegrass and the use of biocontrol agents to manage it. Psychological characteristics including attitudes, knowledge, concern, and environmental values were investigated using an Australia-wide online survey, and respondents were separated into distinct segments using latent profile analysis. This study revealed that, within the sample of stakeholders surveyed, there were two groups that held slightly different views about African lovegrass and the environment, but they did not differ in terms of high levels of support for the potential use of biocontrol agents for African lovegrass. This information provides evidence of strong support for the management of African lovegrass using biocontrol. [ABSTRACT FROM AUTHOR]

The herbicide glyphosate has several potential entry points into composting sites and its impact on composting processes has not yet been evaluated. To assess its impact on bacterial diversity and abundance as well as on community composition and dynamics, we conducted a mesocosm experiment at the Montreal Botanical Garden. Glyphosate had no effect on physicochemical property evolution during composting, while it was completely dissipated by the end of the experiment. Sampling at Days 0, 2, 28 and 112 of the process followed by 16S rRNA amplicon sequencing also found no effect of glyphosate on species richness and community composition. Differential abundance analyses revealed an increase of a few taxa in the presence of glyphosate, namely TRA3‐20 (order Polyangiales), Pedosphaeraceae and BIrii41 (order Burkholderiales) after 28 days. In addition, five amplicon sequence variants (ASVs) had lower relative abundance in the glyphosate treatment compared to the control on Day 2, namely Comamonadaceae, Pseudomonas sp., Streptomyces sp., Thermoclostridium sp. and Actinomadura keratinilytica, while two ASVs were less abundant on Day 112, namely Pedomicrobium sp. and Pseudorhodoplanes sp. Most differences in abundance were measured between the different sampling points within each treatment. These results present glyphosate as a poor determinant of species recruitment during composting. [ABSTRACT FROM AUTHOR]

Weeds exert a pronounced influence on the sugar beet yield, leading to the potential for substantial reductions in agricultural productivity. In pursuit of addressing this issue, two experiments were conducted at the Faculty of Agriculture in Giza, Egypt, during the winter seasons of 2020/2021 and 2021/2022 to investigate the efficacy of various pre- and post-herbicides applied differently in active ingredient percentages, forms, and on weed target types, and mechanical weed treatments on weed traits and sugar beet crop performance. (1) In this context, five herbicidal treatments, including pre-emergence (S-Metoachlor) and post-emergence applications of Betanal Max Pro (Desmedipham 4.7% + Ethofumesate 7.5% + Lenacil 2.7% + Phenmedipham 6%), Tegrospecial (Desmedipham 20% + Phenmedipham 20%) for total annual weeds, C Factor (Haloxyfop-R-Methyl 7.5% + Fluazifop-p-putyl 15%), and Clictar (Clethodium 24%) for grassy weeds, were assessed alongside mechanical weeding and a weedy check (control). (2) The evaluations encompassed growth parameters, juice quality, and beet yields to comprehensively assess the treatment effects. (3) Notably, weed control measures, especially regarding three total annual weeds herbicides and the cultivation when using both grassy weed herbicides, consistently produced the highest improvements in sugar beet root's fresh and dry weights, root dimensions, sucrose content, purity, sugar recovery, as well as the root and recoverable sugar yields, across both seasons. (4) However, it is important to note that the application of Clethodium 24% and Haloxyfop-R-Methyl 7.5% + Fluazifop-p-putyl 15% resulted in elevated levels of sodium, potassium, amino nitrogen, impurities, and sucrose loss to molasses. These findings underscore the substantial influence of herbicide use and mechanical weeding on sugar beet's growth, juice quality, and yield, with S-Metoachlor, Desmedipham 20% + Phenmedipham 20% and Desmedipham 4.7% + Ethofumesate 7.5% + Lenacil 2.7% + Phenmedipham 6%—showing promise as effective weed control options, albeit with certain associated drawbacks. [ABSTRACT FROM AUTHOR]

In agricultural weed management, herbicides are indispensable, yet innovation in their modes of action (MOA)—the general mechanisms affecting plant processes—has slowed. A finer classification within MOA is the site of action (SOA), the specific biochemical pathway in plants targeted by herbicides. The primary objectives of this study were to evaluate the efficacy of hyperspectral imaging in the early detection of herbicide stress and to assess its potential in accelerating the herbicide development process by identifying unique herbicide sites of action (SOA). Employing a novel SOA classification method, eight herbicides with unique SOAs were examined via an automated, high-throughput imaging system equipped with a conveyor-based plant transportation at Purdue University. This is one of the earliest trials to test hyperspectral imaging on a large number of herbicides, and the study aimed to explore the earliest herbicide stress detection/classification date and accelerate the speed of herbicide development. The final models, trained on a dataset with nine treatments with 320 samples in two rounds, achieved an overall accuracy of 81.5% 1 day after treatment. With the high-precision models and rapid screening of numerous compounds in only 7 days, the study results suggest that hyperspectral technology combined with machine learning can contribute to the discovery of new herbicide MOA and help address the challenges associated with herbicide resistance. Although no public research to date has used hyperspectral technology to classify herbicide SOA, the successful evaluation of herbicide damage to crops provides hope to accelerate the progress of herbicide development. [ABSTRACT FROM AUTHOR]

Weed management remains a major challenge in cropping systems worldwide, with rising interest in ecological based approaches that can be integrated with herbicide use. Soil microbial communities may play important, yet undiscovered, roles in weed success. Little is known about the rhizosphere communities associated with weeds like Amaranthus, commonly known as pigweeds, and considered some of the most problematic weeds in agricultural systems. In a greenhouse experiment that allowed controlled plant growth conditions and a high number of individual plant specimens to analyze for statistical robustness (n = 8 per species), we show that specific bacterial assemblages form in the rhizospheres of A. retroflexus L. (redroot pigweed), A. palmeri S. Watson (Palmer amaranth), and A. tuberculatus (Moq.) J. D. Sauer (waterhemp). Using a relatively rapid and easy approach of T-RFLP community profiling of the 16S rRNA genes, distinct assemblages corresponded to plant species (PERMANOVA F = 14.776, p = 0.001), and further within each species, similar communities (F = 11.449, p = 0.001) were associated with three rhizosphere soil fractions taken in increasing distances away from the root tissue. These results provide the first solid basis for distinct plant-microbe relationships within three closely related Amaranthus species, warranting closer examination of the identities and function of the microorganisms that appear to be selectively recruited from the extant soil community. More intensive efforts to obtain the microbial taxonomic identities via sequencing are underway that can lead to further detailed studies to elucidate important functional plant-microbe interactions that may associate with weed success. Such data provides underlying key information that may ultimately exploit weed-microbe interactions in development of new integrated weed control tactics. [ABSTRACT FROM AUTHOR]

Herbicides are small molecules that act by inhibiting specific molecular target sites within primary plant metabolic pathways resulting in catastrophic and lethal consequences. The stress induced by herbicides generates reactive oxygen species (ROS), but little is known about the nexus between each herbicide mode of action (MoA) and their respective ability to induce ROS formation. Indeed, some herbicides cause dramatic surges in ROS levels as part of their primary MoA, whereas other herbicides may generate some ROS as a secondary effect of the stress they imposed on plants. In this review, we discuss the types of ROS and their respective reactivity and describe their involvement for each known MoA based on the new Herbicide Resistance Action Committee classification. [ABSTRACT FROM AUTHOR]

We characterized the chemical compounds present in the extract of dry leaves from Duranta erecta L. using ESI-MSn mass spectrometry and assessed their phytotoxic potential on Lactuca sativa L.. The extraction process involved exhaustive extraction with 50% ethanol, and the resulting extracts were subsequently dried through lyophilization. Solutions of 2.5, 5, 10, 20, and 40 mg/mL concentrations were prepared from the dried extracts to investigate their allelopathic effects on L. sativa, focusing on germination, germination speed, root elongation, shoot length, and fresh biomass. Statistical analysis was performed using Analysis of Variance, and means were compared using the Scott-Knott test (p < 0.05). The ESI-MSn analysis identified a total of 20 compounds in the extract, with 12 of them being reported for the first time in Duranta sp. Our findings suggest that D. erecta possesses allelopathic potential, as evidenced by its cytotoxicity, mitodepressive effects, and phytotoxicity on germination and morphological parameters in the bioassay conducted with L. sativa. [ABSTRACT FROM AUTHOR]

Wetlands provide essential habitat for a wide variety of wildlife species. In the once wetland‐rich Prairie Pothole Region and adjacent areas of central North America, many wetlands have been converted to agricultural production. Many remaining wetlands experience ecological change via the invasion and spread of non‐native plant species, such as non‐native narrowleaf (Typha angustifolia) and hybrid cattail (Typha x glauca), which spread aggressively and displace native vegetation, especially in large, impounded wetlands. Management of wetlands in these landscapes often includes broad‐scale herbicide application intended to break up mats of cattail and restore areas to more wildlife‐friendly conditions. Although restoration of wildlife habitat is a common goal of such management, marshbird response to invasive cattail control is poorly understood. To evaluate the effects of cattail management on wetland wildlife, we conducted standardized call‐broadcast surveys for 5 species of marshbirds at 9 study sites that included survey locations associated with areas treated with herbicide and paired areas not treated with herbicide in wetland impoundments in northwestern Minnesota, USA, using a before‐after, control‐impact study design. We surveyed American bitterns (Botaurus lentiginosus), least bitterns (Ixobrychus exilis), pied‐billed grebes (Podilymbus podiceps), soras (Porzana carolina), and Virginia rails (Rallus limicola) during the breeding season prior to herbicide application (late summer and early autumn of 2015) and during the 3 breeding seasons after herbicide application (2016–2018). We modeled species counts using a generalized linear mixed model with year‐by‐treatment interactions as fixed effects and site as a random effect. Before herbicide application, expected mean counts did not differ between treatment and control survey locations. Three years post‐treatment, we detected significant increases in expected mean counts at treatment compared to control survey locations for soras (t193 = −3.373, P = 0.020) and Virginia rails (t193 = −3.167, P = 0.037), and point estimates for all species except least bittern were higher at treatment survey locations. Overall, our results suggest that these marshbird species responded positively to herbicide control of invasive cattail and that breeding marshbirds in these and similar wetland systems may experience positive population response over a period of at least 3 years following treatment. [ABSTRACT FROM AUTHOR]

Microbiological variables can be sensitive indicators of changes in the physicochemical properties of soils resulting from disturbances caused by practices of weed management. The objective of this work was to evaluate the impact of weed management strategies on the soil, using microbiological indicators over four-year time measures (two in the dry and two during the rainy weather season). The experiment was carried out in a coffee plantation field (Coffea arabica), in a randomized block design with five treatments. The treatments corresponded to the cultivation of Urochloa ruziziensis and Pueraria phaseoloides managed by mowing, maintenance of spontaneous vegetation and control by mowing, control of spontaneous vegetation by application of herbicides (glyphosate or glyphosate + 2,4-D), and manual weeding using a hoe to maintain the soil without vegetation cover. Soil C – CO2 evolution, basal respiration (RR), biomass carbon (Cbio), and metabolic quotient (qCO2) were evaluated. Treatments with U. ruziziensis and P. phaseoloides presented lower qCO2 values, indicating more stable systems and closer to equilibrium. Cbio was higher in the treatment with P. phaseoloides, indicating better soil fertility and carbon input conditions. The microbiological indicators allowed us to conclude that management methods that form a cover over the soil favor the maintenance of soil quality and the sustainability of the system. [ABSTRACT FROM AUTHOR]

Weed management in upland rice under subtropical climate with high rainfall is challenging. The diverse weed flora in upland rice ecosystem emerges in several flushes, necessitating sequential application of herbicides. A 4-year study conducted in Meghalaya (950 m above sea level), India indicated that sequential application of Cyhalofop butyl [2-{4-(4-cyano-2-fluorophenoxy) phenoxy} propionic acid, butyl ester (R)], a grass weed killer high efficacy low volume herbicide applied 80 g ha−1 at 25 days after sowing (DAS) and 2,4-D, a broadleaf weed killer herbicide applied 0.75 kg ha−1 at 35 DAS was effective for weed control and produced significantly higher grain yield (3572 kg ha−1) of rice with the highest weed control efficiencies than other treatments. Application of Pretilachlor followed by (fb) 2,4-D or Fenoxaprop-p-ethyl fb 2,4-D yielded significantly higher chlrophyll (chl) a, chl b and total leaf chl content compared with other herbicides at 90 DAS. The highest net energy (111,443 MJ ha−1), energy profitability and benefit:cost ratio was recorded with sequential application of Cyhalofop butyl and 2,4-D. Thus, sequential application of Cyhalofop butyl and 2,4-D could provide a sustainable weed management option in upland rice under high rainfall conditions in the Eastern Himalayas, India. [ABSTRACT FROM AUTHOR]

Glyphosate is the most commonly used agricultural herbicide in the world. In aquatic ecosystems, glyphosate often adsorbs to benthic substrates or is metabolized and degraded by microorganisms. The effects of glyphosate on microbial communities vary widely as microorganisms respond differently to exposure. To help understand the impacts of glyphosate on the sediment microbiome, we conducted a microcosm experiment examining the responses of benthic sediment microbial communities to herbicide treatments. Sediments from a prairie pothole wetland were collected, and 16S rRNA gene sequencing was used to analyze community composition 2-h and 14-days after a single treatment of low (0.07 ppm), medium (0.7 ppm), or high (7 ppm) glyphosate, aminomethylphosphonic acid (glyphosate metabolite), or a glyphosate-based commercial formula. We found no significant differences in microbial community composition across treatments, concentration levels, or day of sampling. These findings suggest that microbial species in the Prairie Pothole Region of North America may be tolerant to glyphosate exposure. [ABSTRACT FROM AUTHOR]

Efficacy of herbicides is strongly affected by weather conditions shortly before and after application. Small‐plot field trials were carried out in winter wheat in north‐west Bohemia, Czech Republic, Central Europe from 2011 to 2018. The relationship between meteorological characteristics and efficacy of acetolactate synthase inhibiting herbicides (mesosulfuron + iodosulfuron, propoxycarbazone and pyroxsulam) on Bromus sterilis was studied. The effects of precipitation before and after herbicide application, mean temperature and sunshine hours after the application were found to be statistically significant. The total precipitation 30 days before herbicide application had the greatest effect on herbicide efficacy. Mean efficacy significantly increased with increasing precipitation, when mean temperatures 5 days after treatment were above 9°C. The herbicide mesosulfuron + iodosulfuron was most affected by amount of precipitation while efficacy of pyroxsulam was minimally affected. When total rainfall amounted to 30 mm in the 20–40 days after herbicide application, there was no significant effect of total rainfall before herbicide application. In order to prepare the best weed control strategy against B. sterilis, weather conditions before and after the application term should be considered so that the growers can adjust for proper application timing and be prepared for a second application with a suitable herbicide. [ABSTRACT FROM AUTHOR]

Over the last decades, biostimulants have been the center of discussion as a sustainable cultivation practice to promote plant growth and protect crops from abiotic stress. Agrochemical products are abundantly used for this purpose, which has resulted in raised international concern. Biostimulants, when used in combination with herbicides in some cases, could act as safeners, reducing the harmful and stressful effects of herbicides, and as a result, this combination can be considered a relatively new agricultural technique. However, they can also have adverse or non-significant effects, something that is strongly affected by the operating mechanisms of their components. In practice, there is a need to identify plant species-biostimulant-herbicide working systems from all the stakeholders of agricultural production. While research is still in its early stages, several studies have been conducted to evaluate various biostimulant and herbicide combinations to contribute to this goal. In this review, studies of their combination in sequential or mixed tank applications have been gathered to see how and if each specific combination can have a potential use in agricultural practice. The results indicated that there are various effects on crops, some of which were positive and others negative or non-significant. The fact that there is a countless number of possible plant species-biostimulant-herbicide combinations to be evaluated is a challenging task. Nevertheless, this review could serve as a foundation for the upcoming research. The aim of this review is to summarize the knowledge of some successful working examples of these three factors that could facilitate the incorporation of biostimulant and herbicide application, either sequentially or in a tank mixture, as a part of the agricultural practice for field crops. [ABSTRACT FROM AUTHOR]

Prickly sida is a troublesome annual weed native to the USA. It was introduced in Greece over two decades ago and has since been infesting cotton crops, where it proved difficult to control. A two-year field study (2021–2022) was conducted in a cotton field (Karditsa, central Greece) heavily infested with prickly sida to evaluate the efficacy of nine treatments against this weed, using pre-emergence (PRE) and early post-emergence (EPOST) herbicides applied at the field rate. At 8 weeks after treatment, prickly sida control was over 90% with pyrithiobac PRE (68.9 g ai ha−1) alone or in mixture with s-metolachlor (960 g ai ha−1) or with isoxaben (150 g ai ha−1) and with the application of pyrithiobac + s-metolachlor PRE (34.5 + 960 g ai ha−1) followed by pyrithiobac EPOST (34.5 g ai ha−1). Flurochloridone + fluometuron PRE (375 + 2000 g ai ha−1), flumioxazin + s-metolachlor PRE (50 + 960 g ai ha−1), or pendimethalin + terbuthylazine PRE (1500 + 750 g ai ha−1) controlled prickly sida by 89–93% in 2021 and 82–90% in 2022. Pyrithiobac EPOST alone or in mixture with trifloxysulfuron did not adequately control prickly sida. Yield was significantly lower in the weedy check and EPOST compared with the PRE treatments. None of the herbicides caused any visual injury to the crop or any reduction in cotton density. Our results can help in the successful management of prickly sida in non-transgenic cotton to maximize cotton yield and quality. [ABSTRACT FROM AUTHOR]

Simple Summary: Gut microbiomes can influence host health and fitness. Pollutants, including antibiotics, tend to alter microbiomes. We examined the role of an undisturbed gut microbiome on tadpole health and morphology in the Rio Grande Leopard frog, Rana berlandieri. We exposed tadpoles to four treatments (1) control: clean water, (2) Roundup®: the active ingredient is glyphosate, the main herbicide used in the United States, (3) antibiotic cocktail, to disrupt the natural microbiome of the tadpoles, and (4) combination: Roundup and antibiotic cocktail. We found that the gut microbial community significantly changed across treatments. Tadpoles in the antibiotic and combination treatments were least active and the smallest compared to the other treatments. Our results provide evidence that the gut microbial communities of tadpoles are sensitive to herbicides and antibiotics, which may have an impact in host phenotype and fitness via altered behavior and growth. This study provides important insights for conservation of amphibians and into the consequences of current agricultural practices. The gut microbiome is important for digestion, host fitness, and defense against pathogens, which provides a tool for host health assessment. Amphibians and their microbiomes are highly susceptible to pollutants including antibiotics. We explored the role of an unmanipulated gut microbiome on tadpole fitness and phenotype by comparing tadpoles of Rana berlandieri in a control group (1) with tadpoles exposed to: (2) Roundup® (glyphosate active ingredient), (3) antibiotic cocktail (enrofloxacin, sulfamethazine, trimethoprim, streptomycin, and penicillin), and (4) a combination of Roundup and antibiotics. Tadpoles in the antibiotic and combination treatments had the smallest dorsal body area and were the least active compared to control and Roundup-exposed tadpoles, which were less active than control tadpoles. The gut microbial community significantly changed across treatments at the alpha, beta, and core bacterial levels. However, we did not find significant differences between the antibiotic- and combination-exposed tadpoles, suggesting that antibiotic alone was enough to suppress growth, change behavior, and alter the gut microbiome composition. Here, we demonstrate that the gut microbial communities of tadpoles are sensitive to environmental pollutants, namely Roundup and antibiotics, which may have consequences for host phenotype and fitness via altered behavior and growth. [ABSTRACT FROM AUTHOR]

Nowadays, the trend to benefit from environmentally friendly waste and recycle it instead of incineration processes that can cause pollution in the environment to have a clean and green environment that is free from pollution and can work for a long time without consumption and damage. This study is designed to manufacture prosthetics limbs from PMMA (polymethyl methacrylate) reinforced with different weight percentages of waste paper layers (0%, 3%, 6%, 9%, and 12%) by the “hand lay” method. The tensile, flexural, impact, compression, and hardness of these composites are tested before and after adding weight percentages waste paper layers to determine the mechanical properties behavior. The average values of all the samples are collected and analyzed by one-way analysis of variance (ANOVA) to interpret the results. When discussing the results of mechanical tests, it is found that the addition (12%-waste paper layers) to (PMMA) increased the average values (tensile, flexural, impact, compression, and hardness) by 142.1%, 532.3%, 146%, 99.2%, and 6.37%; respectively, compared to the mean values of other samples. It is clear from this work there is an improvement in the properties of PMMA after strengthening with waste paper layers. [ABSTRACT FROM AUTHOR]

Land managers rely heavily on herbicides to mitigate exotic plant invasions but the nontarget effects of herbicides on treated plant, animal, and soil communities are often overlooked. Biological soil crusts (biocrusts) are important components of ecosystems yet the effects of different herbicides on biocrusts are rarely considered. We tested the impact of three widely used herbicides, indaziflam, imazapic, aminocyclopyrachlor, and chlorsulfuron, two of which were applied with or without a surfactant, on biocrusts dominated by mosses or lichens in intermountain grasslands. We found that neither the herbicides nor surfactant impacted biocrust moss or lichen cover within 2 years of their application. [ABSTRACT FROM AUTHOR]

Questions: Selective herbicides are frequently used in ecological restoration to control invasive non‐native forbs and recover plant communities. However, the long‐term efficacy of this practice, its non‐target effects on native plants, and its role in facilitating secondary invasions are not well understood. Similarly, little is known about the extent to which herbicide drift may affect native plant communities. Location: Foothills grasslands of Montana, USA. Methods: We conducted a 6‐year experiment to investigate changes in the abundance of a target invasive plant, knapweed (Centaurea stoebe subsp. micranthos) and plant community structure in response to the herbicides Tordon® (picloram) and Milestone® (aminopyralid), applied at a recommended rate and a diluted rate that simulated drift. Results: Knapweed cover and the richness of native and non‐native forb species declined in the first 3 years in response to treatment at recommended rates, but not drift rates. Secondary invasion by non‐native monocots was significant but weak. The cover of native forbs and the cover and richness of native monocots did not differ among treatments but changed significantly with the year. Surprisingly, 6 years after treatments, there were no differences among treatments in the cover of the target invasive plant or community structure. Conclusions: Our results demonstrate that the efficacy and non‐target effects of herbicides in grassland restoration can be short‐lived and idiosyncratic because of year effects. Restoration of knapweed invasions might require other active interventions, such as seeding or repeated spraying. Our study supports previous calls for long‐term monitoring of herbicides application in ecological restoration. [ABSTRACT FROM AUTHOR]

Cultivation and grazing since the mid-nineteenth century in Texas has caused dramatic changes in grassland vegetation. Among these changes is the encroachment of native and introduced brush species. The distribution and quantity of brush can affect livestock production and water holding capacity of soil. Still, at the same time, brush can improve carbon sequestration and enhance agritourism and real estate value. The accurate identification of brush species and their distribution over large land tracts are important in developing brush management plans which may include herbicide application decisions. Near-real-time imaging and analyses of brush using an Unoccupied Aerial System (UAS) is a powerful tool to achieve such tasks. The use of multispectral imagery collected by a UAS to estimate the efficacy of herbicide treatment on noxious brush has not been evaluated previously. There has been no previous comparison of band combinations and pixel- and object-based methods to determine the best methodology for discrimination and classification of noxious brush species with Random Forest (RF) classification. In this study, two rangelands in southern Texas with encroachment of huisache (Vachellia farnesianna [L.] Wight & Arn.) and honey mesquite (Prosopis glandulosa Torr. var. glandulosa) were studied. Two study sites were flown with an eBee X fixed-wing to collect UAS images with four bands (Green, Red, Red-Edge, and Near-infrared) and ground truth data points pre- and post-herbicide application to study the herbicide effect on brush. Post-herbicide data were collected one year after herbicide application. Pixel-based and object-based RF classifications were used to identify brush in orthomosaic images generated from UAS images. The classification had an overall accuracy in the range 83–96%, and object-based classification had better results than pixel-based classification since object-based classification had the highest overall accuracy in both sites at 96%. The UAS image was useful for assessing herbicide efficacy by calculating canopy change after herbicide treatment. Different effects of herbicides and application rates on brush defoliation were measured by comparing canopy change in herbicide treatment zones. UAS-derived multispectral imagery can be used to identify brush species in rangelands and aid in objectively assessing the herbicide effect on brush encroachment. [ABSTRACT FROM AUTHOR]

Background: Weeds are the major biotic constraint to reduce the rice productivity in direct wet seeded rice. Weed infestation and competition are severe in direct wet seeded rice as compared to transplanted rice, because of the simultaneous growth of both crops and weeds. The yield loss due to weeds varies from 40 to 100 per cent in direct seeded rice. Use of herbicides either singly or in combination with manual or mechanical weeding in puddled direct seeded rice has been highlighted by several workers. Use of alternative herbicides with wide spectrum control of the weeds in direct seeded puddled rice is the need of the present time. The present study aimed to evaluate different weed management practices in direct wet seeded rice under sodic soil. Methods: A field experiment was conducted during Samba season (Rabi) 2016-17. To evaluate the weed management practices in direct wet seeded rice under sodic soil. The treatments comprised of different combination of weed management practices viz., pre emergence, early post emergence herbicides, mechanical weeding and hand weeding twice were tested. Total weed density and weed dry weight, weed control efficiency, yield parameters and yield of rice were recorded. Result: Among the different weed management practices, the lowest total weed density, total weed dry weight and higher WCE, yield attributes, grain and straw yields were registered under application of PE pyrazosulfuron ethyl 25 g/ha fb EPOE bispyribac sodium 25 g/ha. This was followed by application of PE pretilachlor 0.75 kg/ha fb EPOE bispyribac sodium 25 g/ha. [ABSTRACT FROM AUTHOR]

Background: Ongoing controversy exists regarding terminology used to describe atypical melanocytic nevi. Efforts to standardize nomenclature, including the 1992 NIH consensus conference, have been largely unsuccessful. Significant advances have revealed an increasingly detailed genetic picture of melanocytic neoplasms, including strong evidence for the existence of those with "intermediate" behavior. Methods: We sent an electronic survey to dermatopathologists (n = 846) to assess trends in nomenclature usage and attitudes toward developing new consensus nomenclature for atypical melanocytic nevi. Results: There were 229 complete responses (27.1% response rate). The most used/preferred nomenclature was "dysplastic nevus" (43%/39%, respectively), followed by the NIH‐recommended terminology (28%/26%). Three‐tier grading systems were most heavily used/preferred (79%/63%). Dermatopathologists based in New England were most likely to use the NIH terminology; on the other hand, "dysplastic nevus" or "other" were most used elsewhere (p = 0.029). Most (76%) expressed at least "moderate" enthusiasm for developing consensus nomenclature, with 47% "very" or "extremely" enthusiastic. Conclusion: Little has changed with the wide variation in terminology for atypical melanocytic nevi. There continues to be no one dominant terminology in use. However, there is enthusiasm for standardization. A new attempt at updated consensus nomenclature may be fruitful. [ABSTRACT FROM AUTHOR]

The present study has been carried out in C. batrachus to evaluate the oxidative stress induced by herbicide pretilachlor through analysing level of lipid peroxidation (LPO) and activities of different antioxidant enzymes in liver tissue. Fish were exposed to different sub lethal test concentrations of pretilachlor based on 96 h LC50 value. The durations of exposure were 30, 45 and 60 days. Herbicide concentration and exposure duration dependent changes in the level of lipid peroxidation and antioxidant enzyme activities were observed. Maximum level of LPO was observed in fish exposed to maximum test concentration of herbicide at all duration of exposure. For a particular test concentration the maximum LPO was seen at 45 days which was followed by decrease at 60 days of exposure. In a similar way, activities of Superoxide dismutase (SOD) and catalase (CAT) increases with increasing duration of exposure initially and then decreases. No significant changes in GR activity was observed because GSH: GSSG ratio is more resistant to exposure of pretilachlor. Results clearly indicated that herbicide pretilachlor changes the antioxidant status of fish therefore its excessive and improper use in agricultural fields must be avoided. [ABSTRACT FROM AUTHOR]

Wildflowers attract wildlife, increase pollinator habitat, and enhance the aesthetic value of the landscape. Wildflower establishment is increasingly part of an effort to reduce maintained turfgrass on golf courses, lawns, and other maintained environments. Weed competition decreases wildflower establishment and results in poor long-term stands. Research was conducted in a controlled environment to investigate the tolerance of wildflower species to common postemergence herbicides. Wildflower species included California poppy (Eschscholzia californica Cham.), common sunflower (Helianthus annuus L.), cornflower (Centaurea cyanus L.), garden coreopsis (Coreopsis lanceolata L.), partridge pea [Chamaecrista fasciculata (Michx.) Greene], plains coreopsis (Coreopsis tinctoria Nutt.), purple coneflower [Echinacea purpurea (L.) Moench], rosering gaillardia (Gaillardia pulchella Foug.), and violet prairie clover (Dalea purpurea Vent.). Herbicides evaluated were fluazifop at 0.28 kgha-1 a.i., mesotrione at 0.14 kgha-1 a.i., clopyralid at 0.29 kgha-1 a.i., bentazon at 0.56 kgha-1 a.i., halosulfuron at 0.053 kgha-1 a.i., and imazaquin at 0.42 kgha-1 a.i. An untreated check was included for comparison. Excessive damage ($ 53% phytotoxicity) was observed on all wildflower species in response to clopyralid, except for California poppy. Fluazifop and bentazon were relatively safe (# 19% phytotoxicity, regardless of herbicide) on all wildflower species; however, bentazon resulted in $ 40% aboveground biomass reduction in several species. Common sunflower and garden coreopsis were susceptible to halosulfuron (37% and 73% phytotoxicity, respectively) and imazaquin (37% and 87% phytotoxicity, respectively), but on all other wildflower species, phytotoxicity was # 18%. Although both halosulfuron and imazaquin only resulted in # 18% phytotoxicity to purple coneflower, a 43% to 44% aboveground biomass reduction was recorded. Mesotrione was only safe on California poppy and cornflower (# 11% phytotoxicity and # 24% aboveground biomass reduction). Results suggest high tolerance variability across herbicides and species considered, but may prompt new investigation of safety and utility within field and production scenarios. [ABSTRACT FROM AUTHOR]

Pelargonic acid is the most successful natural herbicide and can contribute to reducing synthetic herbicides, but information on its efficacy is contrasting. Given its high cost, a reduction of the rate could facilitate the spread of the use of this herbicide. Two greenhouse and three field experiments were conducted to evaluate the herbicidal efficacy of different doses of pelargonic acid on several weeds (Abutilon theophrasti, Alopecurus myosuroides, Conyza sumatrensis, Lolium rigidum, Persicaria maculosa, Setaria pumila, Solanum nigrum). Results show that the efficacy of pelargonic acid is partial both in the greenhouse and field since the sensitivity of weed species is very variable, yet significant weed biomass reduction was observed in field application. Grass weeds, in particular A. myosuroides and L. rigidum, were less sensitive to pelargonic acid, with reduced and transient symptoms even at the highest doses. A large difference in sensitivity was also observed between dicots weeds, with P. oleracea, P. maculosa and A. theophrasti being less sensitive than C. sumatrensis and S. nigrum. The efficacy of pelargonic acid in field conditions depends on the botanical composition of weed flora and environmental conditions. Hot and dry conditions can promote leaf traits that decrease weed sensitivity by reducing herbicide penetration inside leaves. Despite its high cost, pelargonic acid can be a useful tool in an integrated multi-tactic strategy for sustainable weed management, while its use as a stand-alone tactic is less recommendable. [ABSTRACT FROM AUTHOR]

Ammonium sensitivity is considered a globally stressful condition that affects overall crop productivity. The major toxic symptom associated with ammonium nutrition is growth retardation, which has been associated with a high energy cost for maintaining ion, pH, and hormone homeostasis and, eventually, the NH3/NH4+ level in plant tissues. While certain species/genotypes exhibit extreme sensitivity to ammonium, other species/genotypes prefer ammonium to nitrate as a form of nitrogen. Some of the key tolerance mechanisms used by the plant to deal with NH4+ toxicity include an enhanced activity of an alternative oxidase pathway in mitochondria, greater NH4+ assimilation plus the retention of the minimum level of NH4+ in leaves, and/or poor response to extrinsic acidification or pH drop. Except for toxicity, ammonium can be considered as an energy-efficient nutrition in comparison to nitrate since it is already in a reduced form for use in amino acid metabolism. Through effective manipulation of the NH4+/NO3 − ratio, ammonium nutrition can be used to increase productivity, quality, and resistance to various biotic and abiotic stresses of crops. This review highlights recent advancements in ammonium toxicity and tolerance mechanisms, possible strategies to improve ammonium tolerance, and omics-based understanding of nitrogen use efficiency (NUE) in plants. [ABSTRACT FROM AUTHOR]

Background: Groundnut encounters severe infestation of weed especially during the early stages of growth due to less crop canopy which allows higher weeds growth and thus crop becomes more susceptible to weed competition. During rainy season, effective and economical weed control is not possible through manual and mechanical weeding due to unfavorable soil conditions and also the unavailability of costly labours. Herbicides have been accepted as cost effective tool to manage weed menace in groundnut. The current study aims to study the efficancy of different post-emergence and pre-mix combination of post-emergence herbicides on weeds, growth and yield of groundnut. Methods: The field experiment was conducted at AICRP Weed Management Field, Department of Agronomy, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola (M.S.) during three consecutive Kharif seasons of 2015-2017. The experiment was laid out in randomized block design with ten treatments replicated thrice. The treatments comprised of one pre emergence and five different post emergence herbicides and compared with weed free and weedy check. Result: The results revealed that weed free was found most effective to control weeds in groundnut with lowest weed count, weed dry matter of weeds and maximum gross monetary returns (Rs. 117641/ha), net monetary returns (Rs. 80894/ha). Among the herbicides, application of Imazethapyr + Imazomox 0.10 kg/ha POE 20 DAS produced less weed count and weed dry matter and highest weed control efficiency (80.68%) and lower weed index (6.71%) as well as maximum growth, yield attributes and pod yield in groundnut over all the other herbicidal treatments viz. plant height (30.25), dry matter accumulation (18.11 g), number of pods/plant (32.35) and pod yield (2448 kg/ha) and highest pooled B:C ratio (3.74). [ABSTRACT FROM AUTHOR]

The aim of our study was to evaluate the use of Raman spectroscopy for pre-diagnostic estimation of weed response to bleaching herbicides. Model plants were Chenopodium album and Abutilon theophrasti treated with mesotrione (120 g a.i. ha−1). Raman single-point measurements were taken 1, 2, 3, and 7 days after herbicide application from different points on the leaves. Principal component analysis (PCA) was carried out on data normalized by the highest intensity band at 1522 cm−1 and using spectral region from 950 to 1650 cm−1 comprising mainly contributions of carotenoids. The carotenoids by intensive band at ∼1522 cm−1 and bands with lower intensity at ∼1155 and 1007 cm−1 in treated plants were confirmed. According to PC1 (the first principal component) and PC2 (the second principal component), the highest intensity bands responsible for treatment differentiation in C. album could be assigned to chlorophyll, lignin, and carotenes. According to PC1 in A. theophrasti leaves the treatment differences could be observed 7 days after mesotrione treatment and PC2 gave a clear separation between all control and treated leaf samples. Raman spectroscopy may be a good complement to invasive analytical methods, in assessing the plant abiotic stress induced by bleaching herbicides. [ABSTRACT FROM AUTHOR]

Johnson grass is one of the most dangerous and difficult to control weeds. The aim of this study was to determine the effect of different control methods on Johnson grass in tomato fields and to investigate the effect of these methods on the phenological stages and yield indicators of tomatoes. The study was carried out during the 2019 and 2020 seasons. The experiment treatments were as follows: hand hoe, mulch, preemergence herbicide pendimethalin (5 L/ha), postemergence herbicide fluazifop-P-butyl (1 L/ha), and control parcels. The number of flowers, the number of branches, and the length of the plant were determined in tomato. The yield and characteristics of the fruit were calculated and the fruits were analyzed. For Johnson grass, the time for germination, flowering, and seed maturity were determined. Plant height, fresh and dry biomass weight of weed, and rhizomes were also calculated. The results of this experiment showed that the best yield was 64.943 kg/ha in the hand hoe and the fluazifop-P-butyl treatment. The lowest density and fresh biomass of Johnson grass were detected in the fluazifop-P-butyl (217.3 stem/m2, 1009.4 g/m2) and the mulch (251.7 stem/m2, 1355.2 g/m2) treatments, respectively. The highest density and fresh biomass were detected in control parcels (448.8 stem/m2, 3239.2 g/m2), and in the pendimethalin treatment (334.2 stem/m2, 1956.4 g/m2), respectively. The percentage of lost yield in the control parcels was 90.1%. Hand hoe was found to be the most effective control method against Johnson grass followed by fluazifop-P-butyl, mulch, and pendimethalin. [ABSTRACT FROM AUTHOR]

In many EU countries, spray applications should comply with increasingly stringent requirements regarding the drift reduction class of spray nozzles. Many farmers fear that the use of drift-reducing nozzles producing coarse droplet spectra may compromise the performance of contact herbicides on small weed targets. This study examined the effects of various ISO 03 drift-reducing flat-fan nozzles (pre-orifice and single and dual flat-fan air induction nozzles) differing in spray drift reduction class and spray pressure (2.5 bar, 5.0 bar) on (1) spray coverage, (2) droplet characteristics and (3) efficiency of contact herbicides bentazon and phenmedipham against cotyledon and 2-leaf stage plants of Chenopodium album and Solanum nigrum. Performance was compared to that of an ISO 03 standard flat-fan nozzle producing a finer droplet size spectrum. All sprayings were performed at a spray volume of 200 L ha−1. In most dose–response experiments, several drift-reducing flat-fan nozzles performed equally well as standard flat-fan nozzles, regardless of herbicide, spray pressure, growth stage or weed species. However, droplet size spectra of air-induction nozzles were too coarse for an adequate spray coverage and efficient application of contact herbicides on cotyledon stage plants of S. nigrum. In addition, the performance of air-induction nozzles in controlling difficult-to-wet C. album weeds with phenmedipham was better at 5.0 bar than at 2.5 bar. In contrast with droplet size characteristics, spray coverage characteristics determined on water sensitive papers were not good proxies for estimating the biological efficiency of contact herbicides. Air induction nozzles at 5.0 bar allow efficient control of 2-leaf targets, but nozzles emitting finer droplet spectra, such as pre-orifice nozzles, should be preferred for controlling cotyledon stage weeds at low-herbicide doses. [ABSTRACT FROM AUTHOR]

Herbicides (HBCs) are extensively used in modern agriculture. However, their potential negative impacts on environmental media have emerged as a significant environmental concern. In this study, we employed positive matrix factorization (PMF) to identify the potential sources of HBCs. Furthermore, we utilized a multi-matrix ecological risk model to assess the risks associated with HBCs in both surface water and groundwater in the black soil region of Northeast China. The findings revealed that the levels of ∑ 15 HBCs in surface water and groundwater ranged from 585.84 to 6466.96 ng/L and 4.80 to 11,774.64 ng/L, respectively. The PMF results indicated that surface runoff and erosion accounted for 50% of the total HBCs in water, serving as the primary sources. All tested HBCs exhibited acute risk values within acceptable levels. The risk index for the ∑ 15 HBCs was categorized as "moderate risk" in 31% of the surface waters and 13% of the groundwaters. However, 4% of the groundwater sampling sites reached the "high risk" level. The chronic risk quotient of ∑ 15 HBCs in surface water and groundwater was 92% and 62% at the "high risk" level, respectively. Interestingly, non-carcinogenic HBCs contributed more significantly to the ecotoxicology of the aquatic system than carcinogenic HBCs. This study provides comprehensive information on the legacy of HBCs in water bodies and emphasizes the potential risks posed by HBCs to aquatic systems. The results obtained from this study could help relevant management authorities in developing and implementing effective regulations to mitigate the ecological and environmental risks associated with HBCs. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective: The toxicology of herbicides, which are currently in use is under-explored. One highly used but under investigated herbicide is pendimethalin. Here we mined high-throughput data from the US National Toxicology Program (NTP) to identify whether pendimethalin possesses an estrogenic capability in human cells. We also evaluated effects of pendimethalin and its reference commercial formulated herbicide Stomp Aqua on the transcriptome profile of three human mammary epithelial cell lines, cancerous MCF-7 and non-cancerous MCF-10 A and MCF-12 A to see whether this compound could have endocrine disrupting effects and if co-formulants present in the commercial formulation could amplify its toxicity. Results: The data mined from the US NTP database suggests that pendimethalin activates estrogen receptors at a concentration of approximately 10?M. MCF-7, MCF-10A and MCF-12A cells were exposed to 10 ?M pendimethalin and Stomp Aqua at an equivalent concentration. Transcriptome analysis showed changes in gene expression patterns implying that pendimethalin affected ubiquitin-mediated proteolysis and the function of the spliceosome. The formulated pendimethalin product Stomp Aqua gave comparable effects suggesting pendimethalin was responsible for the observed transcriptome alterations. Given the lack of information on the exposure to this pesticide, our study prompts the need for biomonitoring studies, especially under occupational use scenarios, to understand if low level exposure to pendimethalin could have endocrine disrupting effects on populations exposed to this compound. A deeper understanding of the exposure and mechanisms of action of this endocrine-disrupting pesticide is needed. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are noteworthy used nanomaterials in a wide array of fields, particularly in the agricultural sector. Plants play a multifarious role in the ecosystem and provide a source of food for mankind. The responsibility of the scientific community is to recognize the deleterious impact of AgNPs (1–100 nm in size) on critical crop growth and development of plants, which is required for the assessment of environmental threats to plant, human, and animal health. The continued use of AgNPs in agriculture areas may have negative effects on plant biochemical and physiological responses. The current context focused mainly on AgNPs uptake, transport, and accumulation on crop plants and summarizes different levels of phytotoxicity of AgNPs on plant functions and focused on mechanisms of phytotoxicity employed by AgNPs. Moreover, some tolerance mechanisms and various survival strategies developed by plants under AgNPs toxicity are discussed. This background provides comprehensive information necessary to facilitate profound understanding of the toxic impacts of AgNPs on crop plants. [ABSTRACT FROM AUTHOR]

False cleavers (Galium spurium L.) is an annual broadleaf weed, commonly found in cereal crops around the world. It reduces crop yields mainly by the competition for nutrients and plant lodging, which decreases the photosynthetic rate of cultivated plants. Two field experiments were carried out in different locations to examine the efficacy of post-emergence herbicides against false cleavers in durum wheat (Triticum durum Desf.). Herbicides that belong to sulfonylureas, triazolopyrimidines, and other groups (e.g., nitriles and synthetic auxins) were applied. The results revealed that the herbicide florasulam + aminopyralid provided low efficacy (57%) against this weed species, while the most effective herbicides were bromoxynil + 2,4-D and halauxifen-methyl + florasulam. Bromoxynil + 2,4-D efficacy against false cleavers was 73% and 97% at Domokos and Velestino, respectively, while halauxifen-methyl + florasulam efficacy ranged between 89% and 97%. Moreover, the herbicides metsulfuron-methyl + bensulfuron-methyl and pyroxsulam/florasulam + 2,4-D provided low efficacy (<11%) against false cleavers, revealing resistance to ALS-inhibiting herbicides. Regarding the impact of false cleavers and other weed species on the growth of durum wheat, the results showed that the greatest dry biomass (8508.3–8922.7 kg ha−1 and 13,041.4–13,523 kg ha−1 at Domokos and Velestino, respectively) was found in the bromoxynil + 2,4-D, halauxifen-methyl + florasulam, and weed-free treatments. Similar results were also recorded for 1000-seed weights and crop yields, while there were no statistically significant differences among the treatments for spike length. Finally, our results revealed that the herbicides bromoxynil + 2,4-D and halauxifen-methyl + florasulam effectively controlled the resistant false cleavers population. However, it is important to note that halauxifen-methyl + florasulam was recently registered in Greece and other countries and, thus, should be used sensibly by farmers in a rotation with other herbicides to prevent the development of resistant populations. [ABSTRACT FROM AUTHOR]

• The effects of PS on HTAP characteristics and phytotoxicity were studied. • PS can significantly improve the humification index of HTAP. • PS reduced the proportions of aldehydes, ketones, and N-heterocyclic compounds in HTAP. • PS can reduce the phytotoxicity of HTAP. Hydrothermal technology (HT) has received much attention in recent years as a process to convert wet organic waste into hydrochar. The aqueous phase (HTAP) produced by this process is still a burden and has become a bottleneck issue for HT process development. In this study, we provide the first investigation of the HTAP characteristics, phytotoxicity, and their correlation with persulfate (PS) (PS, 2.0 mmol/g TS)-assisted municipal sludge HT. The results showed that PS accelerated the hydrolysis of protein substances and increased the concentration of NH 4 + by 13.4% to 190.5% and that of PO 4 3− by 24.2% to 1103.7% in HTAP at hydrothermal temperatures of 120 to 240 °C. PS can reduce the phytotoxicity of HTAP by reducing aldehydes, ketones, N heterocyclic compounds, and particle size and by increasing its humification index. The maximum values of the root length and biomass of pakchoi (Brassica chinensis L.) seedlings occurred when electrical conductivity was 0.2 mS/cm of HTAP. This work provided a new strategy for the selection and design of HTAP management strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Herbicides based formulations are conventionally used as wettable powder or as Emulsifiable concentrate. The Emulsifiable Concentrates (EC) are prepared by mixing the active content with solvents and surfactants. However, these formulations have undesirable phytotoxic effects due to hazardous solvent and are unsafe to operators during application. Thus, capsule suspension (CS) formulation is considered as an alternative to EC formulations. In this study, we report the preparation of CS formulation of herbicide oxyfluorfen by polymerizing Methylene diphenyldiisocyanate (MDI) and Ethylenediamine (EDA). Water suspensions of the oxyfluorfen microcapsules were prepared by adding anionic, nonionic, polymeric surfactants and formulation auxiliaries. The study also aimed to determine the effect of surfactant on the stability of the microcapsule suspension. It was found that the nature of surfactant influenced the properties of the formulation. The synthesized microcapsules were characterized by Scanning electron microscope (SEM), Fourier Transform Infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). The microcapsule suspensions were applied on rice crop to establish the safety and its future use instead of oxyfluorfen EC. [ABSTRACT FROM AUTHOR]

Sugarcane expansion has been associated with soil contamination by agrochemicals. Pesticides can affect plant growth, and their mixture might have potentiated effects on exposed species. This research aimed to evaluate the influence of fipronil on the phytotoxicity of 2,4-D on three green manure plant species: Canavalia ensiformis, Dolichos lablab, and Lupinus albus. Plants were exposed (for 21 days, at 25 °C) to a control soil and five concentrations of each pesticide and their combinations (36 treatments, considering a full-factorial approach). Effect concentrations of 50% growth inhibition (EC50) were estimated. No phytotoxicity effects were identified when plants were exposed to different fipronil concentrations (up to 0.12 mg kg−1). All species exposed to 2,4-D showed a decrease in shoot and root length and fresh/dry biomass. L. albus and D. lablab roots showed the highest sensitivity when exposed to 2,4-D among the endpoints (EC50 = 0.02 and 0.05 mg kg−1, respectively), while C. ensiformis roots were the most tolerant (EC50 = 0.98 mg kg−1). However, the interference of fipronil on the toxicity of 2,4-D was not detected in different mixture proportions, indicating no interaction between pesticides. Residues of 2,4-D might also impair other crops' growth, compromise productivity, and limit phytotechnologies for soil recovery. [ABSTRACT FROM AUTHOR]