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Amaranthus palmeri is an aggressive, highly invasive weed that thrives across a wide range of adverse environments worldwide; nevertheless, the mechanisms underlying its rapid expansion remain largely unstudied. Glutathione peroxidase (GPX) is a crucial enzyme within the antioxidant defense system, belonging to the phylogenetic conserved family of oxidoreductases present in all living organisms. Despite its significance, the role of GPX in A. palmeri has not been reported. This study identified eight GPX genes (ApGPXs) in A. palmeri through comprehensive bioinformatics and gene expression analyses. The research examined the characteristics, evolutionary relationships, chromosomal mapping, gene structure, subcellular localization, conserved motifs, and cis-acting elements of these genes, as well as their evolutionary conserved functions in relation to Arabidopsis thaliana GPXs and RT-qPCR analysis under various stress conditions. The ApGPXs were distributed across scaffolds (2, 4, and 12) of the A. palmeri genome. Phylogenetic analysis grouped GPX genes into four subgroups, and conserved motifs were found within certain phylogenetic subgroups. We identified Actin8 as the most stable internal reference gene for A. palmeri under diverse stress conditions. Gene expression analysis revealed that ApGPXs participate in both early and late regulatory responses to oxidative stress induced by NaCl, high temperature, osmotic pressure, and glufosinate ammonium. The Arabidopsis GPX mutant (AT4G31870) exhibited a stronger flg22-induced oxidative burst than the wild type, and qPCR confirmed that AtGPXs contribute significantly to glufosinate ammonium stress responses. Evolutionary analysis found high sequence similarity between ApGPX4 and AT1G63460, as well as ApGPX3 and AT4G11600. Also, ApGPX3 and AT4G11600 shared similar expression patterns under glufosinate ammonium stress. This research presents the first gene family study in A. palmeri and provides foundational insights for future studies in this economically critical species. Our findings establish a framework for mitigating A. palmeri’s impact on crop production and exploring ApGPXs in developing herbicide- and stress-tolerant cultivars. Full article

Cenchrus setaceus is an alien invasive species with significant ecological impact on both natural ecosystems and agricultural areas across the Canary Islands. In this study, we evaluated the allelopathic effects of foliar lixiviates from two endemic species, Artemisia thuscula and Plocama pendula, on Cenchrus setaceus and a group of crop species to assess (i) germination inhibition of the invasive species and (ii) selectivity towards non-target crops. A preliminary trial tested undiluted and diluted forms (1%, 10%) of concentrated lixiviates prepared at a 1:3 (w:v) leaf-to-water ratio, using C. setaceus and Lactuca sativa under growth chamber conditions. In the validation trial, lixiviates prepared at a 1:6 (w:v) ratio were applied directly to C. setaceus and seven crops (Zea mays, Allium cepa, Hordeum vulgare, L. sativa, Solanum lycopersicum, Brassica oleracea, and Raphanus sativus) under both growth chamber and greenhouse conditions. Germination indices were calculated across assays, and plumule and radicle lengths were measured in growth chamber assays. In both trials, C. setaceus germination was inhibited by up to 60% by both ratios of lixiviates (Dunn p < 0.05), with reduced speed and seedling growth (plumule: −37.5%; radicle: −85%). Crop sensitivity varied: A. cepa and H. vulgare showed no significant inhibition; B. oleracea and R. sativus were affected by P. pendula (germination reduced 2.5–2.7×); and Z. mays, L. sativa, and S. lycopersicum exhibited delayed germination and reduced seedling growth under both treatments. These results support the selective use of native plant lixiviates for integrated management of Cenchrus setaceus in sensitive agroecosystems. Full article

The increasing implementation of drift-reduction regulations in agriculture has driven the widespread adoption of drift-reducing spray nozzles. However, concerns remain about their impact on the biological efficacy of foliar-applied herbicides, particularly at early weed growth stages. This study evaluated the bio-efficiency of various drift-reducing flat-fan nozzles across three weed species (Chenopodium album, Solanum nigrum, and Echinochloa crus-galli), two growth stages, and six herbicides differing in mode of action and formulation properties. Dose–response bioassays were conducted using eight nozzle–pressure combinations under controlled greenhouse conditions. Spray characteristics, including droplet size distribution, coverage, contact angle, and surface tension, were quantified to elucidate interactions affecting herbicide efficacy. The results showed that nozzle effects were more pronounced for high-surface-tension formulations and poorly wettable weed targets. Several coarser droplet drift-reducing nozzles (e.g., ID3, APTJ) showed inferior performance in controlling small C. album and S. nigrum targets with bentazon and erectophile E. crus-galli targets with cycloxydim. At the same time, nozzle choice was less critical for tembotrione and nicosulfuron spray solutions, which have low surface tension. Across weed species, growth stages, and herbicides, nozzles producing finer, slower droplets demonstrated superior and more consistent performance compared to those producing larger, faster droplets. These findings offer science-based guidance for selecting nozzle types that balance drift mitigation with effective weed control under current and future regulatory constraints. Full article

Glyphosate is one of the most widely used herbicides in agricultural, horticultural, and urban environments. However, its residue accumulation and oxidative damage pose serious threats to crop health and food safety. In this study, we evaluated the potential of epigallocatechin gallate, a natural polyphenol derived from tea, to alleviate glyphosate-induced stress in melon (Cucumis melo L.). LC-MS/MS analysis revealed that EGCG significantly reduced glyphosate residues in plant tissues. Transcriptome analysis indicated that glyphosate induced extensive transcriptional reprogramming, activating genes involved in detoxification and antioxidant defense. Co-treatment with glyphosate and EGCG partially mitigated this stress response and redirected gene expression toward secondary metabolic pathways, particularly flavonoid and phenylalanine biosynthesis. Under herbicide stress, EGCG restored the transcription of key flavonoid biosynthetic genes, including PAL, C4H, CHI, and OMT. Meanwhile, EGCG also modulated the expression of APX, SOD, and GST, suggesting a selective effect on antioxidant systems. Co-expression network analysis identified key hub genes associated with oxidative stress and flavonoid metabolism. These findings demonstrate the dual regulatory role of EGCG in suppressing acute oxidative stress while enhancing metabolic adaptability, highlighting its potential as a natural additive for reducing herbicide residues in fruit crops. Full article

Microbial herbicides, recognized for their target specificity, environmental compatibility, and simple production processes, hold promising potential for sustainable agriculture. This study isolated a strain of Alternaria gaisen (designated GD-011) from infected Medicago sativa L. in Qinghai Province, China, and evaluated its herbicidal potential through systematic development and efficacy assessment. Using single-factor and orthogonal experimental designs, the optimal sporulation substrate was identified as wheat bran, and the fermentation medium was optimized to consist of 14.5 g wheat bran, 19.4 g wheat middlings, 1.5 g rapeseed cake, and 14.6 g corn flour. Based on colony diameter and OD₆₀₀ measurements, diatomite was selected as the most suitable carrier, while bentonite, humic acid, and polyvinyl alcohol were chosen as the stabilizer, protectant, and dispersant, respectively. Pot trials under controlled conditions demonstrated strong herbicidal activity of GD-011 against three common weed species: Chenopodium album L., Elsholtzia densa Benth., and Galium aparine L. The highest efficacy was observed against C. album, with disease incidence and fresh weight inhibition reaching 80.83% and 79.87%, respectively. Inhibition rates for both E. densa and G. asparine exceeded 60%. A wettable powder formulation developed from GD-011 showed particularly effective control of C. album and E. densa, providing a practical foundation for the application of GD-011 as a novel bioherbicide. Full article

Glyphosate, a widely used herbicide, is under scrutiny for its potential neurotoxic effects. This study investigated whether oral exposure to glyphosate, even at doses currently considered safe in Europe, alters the neurochemical profile of enteric nervous system (ENS) neurons in the porcine jejunum. Fifteen immature female pigs were allocated to three groups: control (C), low-dose (G50; 50 µg/kg b.w./day), and higher-dose (G500; 500 µg/kg b.w./day). Following 28 days of exposure, jejunal samples were subjected to double-labelling immunofluorescence staining for neuronal markers, including Hu C/D and PACAP, CGRP, CART, nNOS, or VAChT. Results revealed dose-dependent neurochemical alterations across all enteric plexuses, with glyphosate increasing the number of neurons expressing PACAP, CGRP, CART, and nNOS, while reducing VAChT-positive neurons. The effect of glyphosate on enteric neurons appeared largely uniform across different plexus types, with more pronounced changes at the higher dose and only minor regional variation. Overall, the findings suggest that glyphosate exposure, even within regulatory limits, may alter the neurochemical profile of enteric neurons in a broadly uniform manner, potentially reflecting responses to oxidative stress or early neurotoxic effects, as reported in previous studies. This study challenges current safety thresholds and emphasises the need to reassess regulatory guidelines, particularly in the context of chronic exposure and potential risks to vulnerable populations. Full article

The continued use of agrochemicals in Valle de Arista, SLP, Mexico, has generated loss of effectiveness of active ingredients and impacts on public health and the environment. To identify environmental and socioeconomic impacts, a quantification method was designed using the Kovach Environmental Impact Quotient and environmental accounting of pesticides (Leach and Mumford) that included agricultural diagnosis and identification of agrochemical impacts. Producers, technical advisors and agrochemicals dealers were surveyed as key agents of tomato (Solanum lycopersicum) and chili pepper crops (Capsicum annuum) due to their economic importance. Gower quotation coefficients were calculated to measure similarity of quantitative, qualitative and dichotomous variables with continuous, discrete and binary characteristics. The use of fungicides (carbendazim and chlorothalonil) showed the greatest environmental impact, followed by insecticides (endosulfan and thiametoxam) and herbicides. The negative externality averaged US$15.60 ha⁻¹ annually, corresponding to 50% of tomato, 31.25% of poblano pepper and 18.75% of serrano pepper. Estimated damages due to the use of greenhouses were 37.7% to the consumer, 21.2% to the worker, 14.8% to aquatic life, 3.6% to birds, 9.2% to bees and 3.3% to insects. Full article

Use of dicamba, an auxin-mimic herbicide, has increased in recent years. Both the effects of dicamba on non-target plants and the determination of a biological model to determine the dicamba ecotoxicity dynamics are important to monitor the correct and safe use of this herbicide. The objectives of this study were to determine the effects of low doses (simulating herbicide drift) and to determine the acute toxicity of dicamba to aquatic bioindicator species (Lemna minor, Pomacea canaliculate, Hyphessobrycon eques, and Danio rerio) and terrestrial non-target plants (Cucumis sativus, Solanum lycopersicum, and Lactuca sativa) in tropical conditions. Measurements of acute toxicity of dicamba at the concentrations that cause 50% of symptoms of injury (LC50) and other biometric variables were performed. Dicamba was virtually non-toxic to all aquatic bioindicator species (LC50 > 118.0 mg L⁻¹), while it was highly toxic to all terrestrial non-target plants (LC50 < 0.5 mg L⁻¹). Severe injury symptoms (70% to 100%) caused by application of low doses of dicamba were found for all non-target terrestrial plants. Severe injury symptoms (70% to 100%) caused by volatilization of dicamba were found only for S. lycopersicum. Since S. lycopersicum was found as the most sensitive non-target plant, showing high injury symptoms caused by dicamba and significant injury from volatilized dicamba, this species is suitable for environmental monitoring of dicamba applications. Full article

Acetolactate synthase (ALS) is an important enzyme in plant branched-chain amino acid biosynthesis and the target of several major herbicide classes. Despite its agronomic importance, the role of ALS genes in stress adaptation in the invasive weed Amaranthus palmeri remains unstudied. In this study, four ApALS genes with high motif conservation were identified and analyzed in A. palmeri. Phylogenetic analysis classified ApALS and other plant ALS proteins into two distinct clades, and the ApALS proteins were predicted to localize to the chloroplast. Gene expression analysis demonstrated that ApALS genes are responsive to multiple stresses, including salt, heat, osmotic stress, glufosinate ammonium, and the ALS-inhibiting herbicide imazethapyr, suggesting roles in both early and late stress responses. Herbicide response analysis using an Arabidopsis thaliana ALS mutant (AT3G48560) revealed enhanced imazethapyr resistance, associated with higher chlorophyll retention. Furthermore, high sequence homology between AT3G48560 and ApALS1 suggests a conserved role in protecting photosynthetic function during herbicide stress. This study provides the first comprehensive analysis of the ALS gene family in A. palmeri and offers important insights into its contribution to stress resilience. These findings establish a vital foundation for developing novel strategies to control this pervasive agricultural weed and present potential genetic targets for engineering herbicide tolerance in crops. Full article

Background: This technical note presents a methodological approach to agrichemical inventory documentation. It complements exposure assessments in field settings with time-restricted observational periods. Conducted in Michoacán, Mexico, this method leverages large language model (LLM) capabilities for categorizing agrichemicals from brief video footage. Method: Given time-limited access to a storage shed housing various agrichemicals, a short video was recorded and processed into 31 screenshots. Using OpenAI’s ChatGPT (model: GPT-4o^®), agrichemicals in each image were identified and categorized as fertilizers, herbicides, insecticides, fungicides, or other substances. Results: Human validation revealed that the LLM accurately identified 75% of agrichemicals, with human verification correcting entries. Conclusions: This rapid identification method builds upon behavioral methods of exposure assessment, facilitating initial data collection in contexts where researcher access to hazardous materials may be time limited and would benefit from the efficiency and cross-validation offered by this method. Further refinement of this LLM-assisted approach could optimize accuracy in the identification of agrichemical products and expand its application to complement exposure assessments in field-based research, particularly as LLM technologies rapidly evolve. Most importantly, this Technical Note illustrates how field researchers can strategically harness LLMs under real-world time constraints, opening new possibilities for rapid observational approaches to exposure assessment. Full article

Weeds are a primary factor affecting sugarcane production and productivity in Thailand. During the late-rainy season, when cultivation is carried out under rainfed conditions, weed competition becomes increasingly severe, prompting farmers to perform secondary weed control using post-emergence herbicides. Therefore, to guide farmers on the appropriate use of herbicides for effective weed management and long-term control during the critical period of sugarcane growth, this study evaluates the effectiveness of pre- and post-emergence herbicides. Conducted in Northeast Thailand using a randomized complete block design (RCBD) with four replications, the experiment revealed that several pre-emergence herbicides, namely pendimethalin + imazapic (825 + 75 g a.i. ha⁻¹), indaziflam (62.5 g a.i. ha⁻¹), and sulfentrazone (875 g a.i. ha⁻¹), and a combination of indaziflam + sulfentrazone (46.88 + 750 g a.i. ha⁻¹) were applied one day after sugarcane planting, demonstrating high weed control efficacy. These treatments significantly reduced the summed dominance ratio (SDR) of both total weed (41.65–78.54%) and dominant weeds (70.13–86.04%), including Digitaria ciliaris (Retz.) Koel., Dactyloctenium aegyptium (L.), Brachiaria distachya (L.) Stapf, and Cyperus rotundus, compared with the no-weeding treatment. In summary, effective weed management in sugarcane fields under late-rainy season can be achieved through the application of pendimethalin + imazapic at 825 + 75 g a.i. ha⁻¹, which produced the highest sugarcane yield (a 139.00% increasing compared with no weeding) and net profit (a 79.75% increasing compared with hand weeding) in loamy sand soil conditions, where D. ciliaris, D. aegyptium, and C. rotundus were dominant weeds. Similarly, indaziflam at 62.5 g a.i. ha⁻¹ yielded the best results (a 71.68% increasing compared with no weeding) and net profit (a 121.04% increasing compared with no weeding) in sandy loam soil, where B. distachya was the only dominant weed. This weed management strategy is potentially transferable to sugarcane production systems in other regions that share comparable soil properties, climatic conditions, and dominant weed species. Full article

Background/Objectives: The herbicide resistance of blackgrass (Alopecurus myosuroides Huds.) is one of the most serious problems in the winter cereal monoculture in Europe. Recently, Greek farmers expressed complaints of reduced susceptibility of this weed to winter wheat herbicides. Keeping this in mind, this study focused on the investigation of blackgrass resistance to herbicides at both phenotypic and molecular levels. Methods: Whole-plant rate-response pot assays were conducted to study the possible evolution of resistance (cross- or multiple-resistance) in a blackgrass population to ACCase- and ALS-inhibiting herbicides. Analysis of the ACCase gene sequence, herbicide metabolism study and competition with winter wheat studies were also conducted. Results: High levels of cross-resistance mainly to the ACCase post-emergence clodinafop-propargyl, medium to fenoxaprop-P-ethyl, cycloxydim, pinoxaden, as well as lower levels of resistance to ALS-inhibitors (mesosulfuron-methyl + iodosulfuron-methyl-sodium and pyroxsulam) were confirmed. In addition, the pre-emergence soil-applied herbicides chlorotoluron + diflufenican and prosulfocarb provided excellent control of the S and R blackgrass populations. The analysis of the ACCase gene sequence revealed a point mutation at position 1781, resulting in an amino acid substitution from isoleucine (Ile) to leucine (Leu). Furthermore, the combined application of the herbicides with piperonyl butoxide (PBO, applied 2 h before herbicide application) indicated that there was herbicide metabolism, which may be mediated by cytochrome P450. The R blackgrass population, when grown in competitive interaction with winter wheat, produced more tillers and aboveground fresh weight compared to the S population and caused greater reduction in winter wheat. Conclusions: The results suggest that a blackgrass population has developed multiple resistance to ACCase- and ALS-inhibiting herbicides, due to ACCase gene mutation and herbicide metabolism. No fitness cost and no compromised competitive ability associated with the blackgrass resistance were observed. Full article

Light-dependent protochlorophyllide oxidoreductase (LPOR, E.C.1.3.1.33) plays a crucial role in the biosynthesis of chlorophyll in plants. Therefore, inactivating LPOR can hinder the production of chlorophyll to achieve the effect of weed control. In this research, utilizing an active substructure splicing method, 20 new 1,2,4-oxadiazole compounds targeting LPOR were synthesized. Among them, compounds 5j, 5k and 5q exhibited superior inhibitory efficacy in greenhouse herbicidal trials. In vitro enzyme activity assays indicated that 5q significantly inhibited Arabidopsis thaliana LPOR (AtLPOR), with an IC₅₀ value of 17.63 μM. Furthermore, compound 5q exhibited superior crop safety and holds potential application prospects for weed management in cotton. Molecular docking and dynamic simulations were employed to elucidate the binding mode and molecular mechanism of 5q with AtLPOR. These experimental and theoretical results indicate that 5q is a promising candidate for the development of novel herbicides targeting LPOR. Full article

The long-term application of traditional chemical herbicides has caused a significant escalation in herbicide resistance of barnyard grass (Echinochloa crus-galli). As an eco-friendly alternative, biological herbicides demonstrate substantial application potential. Acknowledging the growing herbicide resistance of E. crus-galli, this study aimed to screen target bacteria with inhibitory effects on the growth for bio-herbicide development. By using ungerminated E. crus-galli seeds as the screening substrate, a bacterial strain (BFYBC-8) with potent inhibitory activity was isolated and identified as Brucella pseudorignonensis. Pot experiments revealed that inoculation with B. pseudorignonensis BFYBC-8 significantly suppressed E. crus-galli growth, reducing plant height by 16.7% and root length by 85.1%, while markedly inhibiting biomass accumulation. Fluorescent labeling with green fluorescent protein (GFP) showed that BFYBC-8 successfully colonized the root intercellular spaces of E. crus-galli and extended continuously along the tissue matrix. Additionally, the strain’s supernatant metabolic products exhibited exceptional thermostability: inhibitory activity against E. crus-galli was maintained after thermal treatment at 28 °C, 60 °C, 80 °C, and 100 °C. Crucially, the bacterium displayed no toxicity to agronomically important crops such as rice, wheat, and corn. This study highlights B. pseudorignonensis BFYBC-8 as a promising candidate for bioherbicide development and provides an important reference for applying seed-associated pathogenic bacteria in developing bioherbicides for sustainable weed management. Full article

Transgenic insect-resistant maize can effectively control insect pests, which is of great significance to improve maize yield and quality. Transgenic maize LD05 is an insect-resistant and herbicide-tolerant maize independently developed by Shandong Academy of Agricultural Sciences and highly resistant to major lepidopteran pests. In order to study the pest resistance of transgenic maize LD05 in different ecological areas of China, this study conducted a laboratory bioassay, and artificial inoculation test and natural pest investigation in field were carried out in one pilot of each of five maize ecological zones in China. The results of laboratory bioassay showed that transgenic maize LD05 had high resistance to Ostrinia furnacalis (Guenée), Mythimna separata (Walker), Helicoverpa armigera (Hübner) and Spodoptera frugiperda (J. E. Smith), the main lepidopteran pests threatening maize production in China. The results of artificial inoculation test and natural pest investigation in field showed that transgenic maize LD05 had high resistance to major lepidopteran pests in different ecological areas of China, which was consistent with the pest resistance management strategy, and can provide important theoretical basis and technical support for the industrialization of transgenic maize LD05 in the future. Full article