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GH11 endo-xylanases, due to their inherent structural and biochemical properties, are the key to efficient bioconversion of lignocellulosic biomass into value-added products. A GH11 endo-xylanase (XynB) from Bacillus subtilis strain CAM 21 was cloned, over-expressed and purified (Mw∼24 kDa) using Ni-NTA affinity chromatography. XynB showed optimum activity at pH 7.0 and 50°C and was stable (>88%) in a broad range of pH (4-11). The apparent Km , K cat and K cat /Km of XynB were 2.9 mg/ml, 1961.2/sec, and 675.62 ml/mg/sec, respectively using birchwood xylan as substrate. XynB was a classical endo-xylanase as it hydrolyzed birchwood xylan to xylo-oligosaccharides and not xylose. Kinetic stability of XynB at 45-53°C was between 43-182 min. Secondary structure analysis of XynB using far-UV CD spectroscopy revealed presence of 51.85% β strands and 2.64% α helix and was consistent with the homology modeling studies. XynB hydrolyzed the xylan extracted from agro-industrial wastes and fruit/vegetable peels by releasing up to 670 mg/g of reducing sugars. The xylan extracted from weeds ( Ageratum conyzoides, Achyranthes aspera and Tridax procumbens ) had characteristic signatures of hemicelluloses and after XynB hydrolysis showed cracks, peeling and release of up to 135.2 mg/g reducing sugars.

Rodents and weeds are important pests to rice crops in Southeast Asia. The interaction between these 2 major pests is poorly documented. In temperate cereal systems, seeds of grass weeds can be an important food source for rodents and weed cover along crop margins provides important refuge for rodents. In 2012 and 2013, a replicated study (n = 4) in Bago, Myanmar compared 4 treatments (rodents and weeds; no rodents and weeds; rodents and no weeds; no rodents and no weeds) each of 0.25 ha in transplanted rice. Weeds were managed with hand weeding in the wet season, and hand weeding and herbicides in the dry season. Plastic fences were installed to exclude rodents. We examined the weed cover and relative abundance of weed species, rodent damage, rodent population dynamics and rice yield loss caused by rodents and weeds. The dominant rodent species was Bandicota bengalensis. In the dry season, Cyperus difformis was dominant at the tillering stage and Echinochloa crus-galli was the dominant weed species at the booting stage. In the wet season E. crus-galli was a dominant weed throughout the season. Damage by rodents was higher in the dry season. There were larger economic benefits for best weed management and effective rodent control in the dry season (258 US$/ha) than in the wet season (30 US$/ha). Concurrent control of weeds in and around rice fields combined with coordinated community trapping of rodents during the early tillering stage and ripening stage of rice are recommended management options., (© 2019 The Authors. Integrative Zoology published by International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.)

The soil microbiome plays an important role in the establishment of weeds and invasive plants. They associate with microorganisms supporting their growth and health. Weed management strategies, like tillage and herbicide treatments, to control weeds generally alter soil structure going alongside with changes in the microbial community. Once a weed population establishes in the field, the plants build up a close relationship with the available microorganisms. Seeds or vegetative organs overwinter in soil and select early in the season their own microbiome before crop plants start to vegetate. Weed and crop plants compete for light, nutrition and water, but may differently interact with soil microorganisms. The development of new sequencing technologies for analyzing soil microbiomes has opened up the possibility for in depth analysis of the interaction between 'undesired' plants and crop plants under different management systems. These findings will help us to understand the functions of microorganisms involved in crop productivity and plant health, weed establishment and weed prevention. Exploitation of the knowledge offers the possibility to search for new biocontrol methods against weeds based on soil and plant-associated microorganisms. This review discusses the recent advances in understanding the functions of microbial communities for weed/invasive plant establishment and shows new ways to use plant-associated microorganisms to control weeds and invasive plants in different land management systems., (© FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Winter-flooding of ricefields provides foraging habitat to waterfowl, which in return may bring agronomic benefits to farmers. Our study experimentally tested the effect of mallards (Anas platyrhynchos) on the standing stalks and weed seed bank in the Camargue (France), both of which present major challenges for farmers. Three duck densities were tested: (D1) 5 ducks ha(-1) (historical nocturnal density), (D2) 23 ducks ha(-1) (present nocturnal density), and (D3) 300 ducks ha(-1) (Asian rice-duck farming density). The ducks reduced the stalks significantly: -27 % (D1), -52 % (D2), and -91 % (D3). Conversely, they decreased the number of seeds by only 3 % (D3) and the seed mass by about 21 % (D1 and D3), which was not significant. Besides they had no effect on seed species richness. This study clearly demonstrates that the winter-flooding effect on straw decomposition can be enhanced by waterfowl foraging, hence showing an agronomic benefit from ducks to farmers. However, there was no clear effect in terms of seed bank reduction.

Private property accounts for much of the planet's arable land, and most of this has been cleared for agricultural production. Agricultural areas retain only fragments of their original vegetation and this has been detrimental to many native plant and animal species. Habitat restoration and revegetation may be able to reconnect and enlarge existing remnant areas in agricultural landscapes and, thereby, enhance native plant and animal communities. However, conservation initiatives will be successful only if landowners actively participate in restoration actions. This study used four hundred postal questionnaires to assess the degree to which landowners in two regions of south-eastern Australia adopt restoration activities, their opinions regarding remnant and revegetated land and their management actions in these areas. One hundred and seventy nine completed questionnaires were received. Three quarters of respondents had undertaken restoration on their property or were planning to revegetate in the future. Landcare members were most likely to have previously revegetated and future revegetation intentions were best predicted by previous restoration activities and a primary income source that was off-farm. Landowners were more likely to manage restored and remnant areas if they perceived threats such as weeds, pest animals and fire risk would be detrimental to their property, than to enhance environmental outcomes. These results indicate that landowners are interested in restoring natural areas, but without greater assistance to restore ground layers and manage perceived threats posed by fire and invasive plants and animals, restoration actions will not have their desired biodiversity benefits., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The metabolism and toxicology of the herbicide 2, 4, 5-T are reviewed. (BB)

Discussed is the use of the herbicide 2,4-D. Though written for farmers and agricultural workers, the pamphlet considers turf weed control and use of 2,4-D near ornamental plants. Aspects of the use of this herbicide covered are: (1) the common forms of 2,4-D; (2) plant responses and tolerances to the herbicide; (3) dilution and concentration of the chemical; and (4) spraying. Much of the information on spraying 2,4-D involves use on crops and problem weeds like Canada thistle and field bindleweed. Other parts discuss spraying 2,4-D on turf, along fence rows and ditch banks, and for control of aquatic weeds. Some general information on sprayers and application techniques is given. In general, the information in this bulletin is non-technical and introductory in nature. (MR)

Presented is a brief review of plant growth substances and selective herbicides. Topics include herbicidal selectivity and inhibitors. (BB)

The history of the development of the herbicide industry, particularly the phenoxy herbicides 2, 4-D, and 2, 4, 5-T,is presented. (BB)

Phenotypic plasticity can alter traits that are crucial to population establishment in a new environment before adaptation can occur. How often phenotypic plasticity enables subsequent adaptive evolution is unknown, and examples of the phenomenon are limited. We investigated the hypothesis of plasticity-mediated persistence as a means of colonization of agricultural fields in one of the world's worst weeds, Raphanus raphanistrum ssp. raphanistrum. Using non-weedy native populations of the same species and subspecies as a comparison, we tested for plasticity-mediated persistence in a growth chamber reciprocal transplant experiment. We identified traits with genetic differentiation between the weedy and native ecotypes as well as phenotypic plasticity between growth chamber environments. We found that most traits were both plastic and differentiated between ecotypes, with the majority plastic and differentiated in the same direction. This suggests that phenotypic plasticity may have enabled radish populations to colonize and then adapt to novel agricultural environments. [ABSTRACT FROM AUTHOR]

Saudi Arabia has implemented ambitious environmental protection programs by creating numerous nature reserves throughout the country. Establishment of the latter nature reserves has led to farm abandonment and the initiation of ecosystem recovery processes. Agricultural practices are known to impact the structure and physicochemical properties of soils while also often markedly affecting natural ecosystem restoration processes. Moreover, weed proliferation in crop fields may modify soil seed banks (SSB), thereby impacting subsequent vegetation recovery. Therefore, it is essential to assess SSB compositions in degraded sites, such as abandoned farms (AF), so as to identify weed species and design efficient restoration strategies in hyperarid ecosystems. In this study, SSB compositions in upper and deep soil layers, standing vegetation compositions, and soil chemical properties were analyzed and compared for two natural ecosystems (NE), two abandoned orchards (AO), two AF, and two natural evaporite basins (EB). NE, AO, AF, and EB all exhibited similar chemical properties, suggesting that former agricultural activities have been guided by a fine understanding of the local environments. Agriculture had impacted the species composition of the observed standing vegetation and germinable SSBs, which could be partly explained by soil property modifications. The findings highlighted that SSBs would warrant detailed study prior to designing ecological restoration strategies, and that the drivers of horizontal and vertical weed dissemination in hyperarid ecosystems should also be explored to gain further insight into weed proliferation patterns and to adapt restoration strategies accordingly. [ABSTRACT FROM AUTHOR]

In the field of object detection, enhancing algorithm performance in complex scenarios represents a fundamental technological challenge. To address this issue, this paper presents an efficient optimized YOLOv8 model with extended vision (YOLO-EV), which optimizes the performance of the YOLOv8 model through a series of innovative improvement measures and strategies. First, we propose a multi-branch group-enhanced fusion attention (MGEFA) module and integrate it into YOLO-EV, which significantly boosts the model's feature extraction capabilities. Second, we enhance the existing spatial pyramid pooling fast (SPPF) layer by integrating large scale kernel attention (LSKA), improving the model's efficiency in processing spatial information. Additionally, we replace the traditional IOU loss function with the Wise-IOU loss function, thereby enhancing localization accuracy across various target sizes. We also introduce a P6 layer to augment the model's detection capabilities for multi-scale targets. Through network structure optimization, we achieve higher computational efficiency, ensuring that YOLO-EV consumes fewer computational resources than YOLOv8s. In the validation section, preliminary tests on the VOC12 dataset demonstrate YOLO-EV's effectiveness in standard object detection tasks. Moreover, YOLO-EV has been applied to the CottonWeedDet12 and CropWeed datasets, which are characterized by complex scenes, diverse weed morphologies, significant occlusions, and numerous small targets. Experimental results indicate that YOLO-EV exhibits superior detection accuracy in these complex agricultural environments compared to the original YOLOv8s and other state-of-the-art models, effectively identifying and locating various types of weeds, thus demonstrating its significant practical application potential. [ABSTRACT FROM AUTHOR]

Crop productivity is affected by various abiotic and biotic factors. Weeds act as the most serious biological constraint by reducing crop yield, harbouring insect pests and causing serious health hazards. Chemical herbicides were widely employed for weed control in agricultural fields. However, an increase in herbicide-resistant weeds and rising environmental concerns arising from the overuse of synthetic herbicides have led scientists to explore natural ways of managing weeds that are cost-effective and environment-friendly. Ecological control by allelopathic crops has proved to be of great significance in weed management. This review focuses on the problem of herbicide resistance in weeds and the role of allelochemicals in biological weed control. Additionally, the review includes the discussion on the allelopathic potential of various crop plants for weed control which can be exploited for the development of cost-effective and environment-friendly bioherbicide. Further, the discussion on retention and biodegrability of the allelochemicals in rhizosphere along with the studies involving genetic mechanisms underlying allelopathy that will direct the future researches for further progress using allelopathy as a potential tool in sustainable agriculture. [ABSTRACT FROM AUTHOR]

Background:Methods:Results:Conclusions:Ripgut brome (Bromus diandrus Roth) is a problematic weed in New Zealand cereals and has developed resistance to various herbicides worldwide, including ACCase, ALS, and EPSPS inhibitors. A population in New Zealand's South Island from wheat recently showed resistance to the ALS-inhibitor pyroxsulam. This study investigates the resistance level in this population.The resistant ripgut brome population was compared to a susceptible population from a nearby organic farm. The level of resistance to pyroxsulam was determined using dose–response assays. The cytochrome P450 inhibitor malathion was used to evaluate the possible role of cytochrome P450 in herbicide metabolism.The estimated LD50 for pyroxsulam in the resistant population was significantly higher (126 g ai ha−1), suggesting a 20-fold reduction in sensitivity compared to the control (6 g ai ha−1). Malathion pre-treatment increased herbicide sensitivity in susceptible and resistant populations.This study confirms significant resistance to pyroxsulam in a New Zealand ripgut brome population and suggests that a target-site resistance mechanism is the most likely explanation. This research adds to global evidence that ripgut brome can become resistant to pyroxsulam and underscores the escalating issue of herbicide-resistant weeds in New Zealand agriculture. [ABSTRACT FROM AUTHOR]

Pre‐emergent herbicides can reduce the abundance of invasive annual plants, but they can also harm native plants, particularly annuals or perennial seedlings, including seeds planted during restoration. We assessed the effects of imazapic and indaziflam on invasive target and nontarget native plants in the Great Basin, a region with extensive invasive annual grasses. We tested nontarget effects on native annual forbs in an agricultural field previously used to grow native annual forbs, which contained a large seed bank. We seeded perennial grass (Elymus elymoides) at multiple depths to determine susceptibility and resistance. Herbicides were applied at full and reduced rates to mimic the effect of litter in natural systems. We observed reductions in most non‐native species in all treatments, but also extensive reductions of native annual forbs, although these were offset at lower application rates, and some species (e.g. Amsinckia tessellata and Microsteris gracilis) were less susceptible than others. Herbicides, particularly indaziflam, reduced E. elymoides emergence, but planting seeds at 2–3 cm depths improved emergence, particularly for imazapic, with 15–68% greater emergence than seeds planted at 1 cm. We suggest surveys for native annual forbs and resistant invaders before applying herbicides and field testing to determine whether reduced rates could provide weed control while maintaining annual forbs. We suggest planting E. elymoides at 2–3 cm when applying herbicides, an approach that may be effective for other species. Herbicide use can be an effective tool, but our results indicate that mitigation of nontarget effects will be needed to maintain native plant diversity. [ABSTRACT FROM AUTHOR]

Field experiments were carried out at two sites to test the responses of weeds in cowpea crop to soil incorporation and surface mulching of corn residue alone or in combination with 50% rate of trifluralin herbicide. Conventional and zero tillage systems without corn residues, half of label rate and full label rate of trifluralin were included for comparison. Incorporated or mulched corn residues significantly reduced weed density and dry weight compared to conventional tillage treatment (control) at both sites. Residue incorporation and mulching plots in combination with 50% of label rate of trifluralin revealed significantly lower weed numbers and dry weight as compared to their respective controls. Soil incorporation and surface mulching of corn residue in combination with 50% rate of trifluralin achieved similar weed control and cowpea grain yield when compared to the 100% trifluralin treatment. Plots amended with corn residue showed greater levels of phenolics. Also, the periods of maximal suppressive effect against the test weed coincided with periods of maximum phenolic content, indicating the possible involvement of phenolics in weed suppression. Combination of allelopathic residues and a reduced rate of herbicides could reduce herbicide usage in agricultural systems while the weed control is not compromised. [ABSTRACT FROM AUTHOR]

The proliferation of weeds in agricultural fields competes directly with crops for essential resources such as, leading to reduced crop yields and economic profitability. The objective of this study was to evaluate the effect of weed management practices on dry bean productivity and economic profitability. Field experiments were conducted between 2018 and 2019 following a Randomized Complete Block Design with four replications and seven treatments. The treatments included: MW (Manual hoe weeding 21DAS), H1 (paraquat 3 l ha−1), H2 (acetochlor 3 l ha−1), H3 (atrazine 3 l ha−1), H1H2 (paraquat 1.5 l ha−1plus acetochlor 1.5 l ha−1), H1H3 (paraquat 1.5 l ha−1 plus atrazine 1.5 l ha−1) and H2H3 (atrazine 1.5 l ha−1 plus acetochlor 1.5 l ha−1). Dry seed yield obtained in 2018 were similar regardless of treatments. However, in 2019, among the herbicides, H1 induced the highest yield (1t ha−1), while the lowest (0.45 t ha−1) was recorded with H2. In addition, the decrease in yield under MW (0.86 t ha−1) was due to the high density of following species: Cynodon dactylon, Commelina benghalensis, Imperata cylindrica, Bidens pilosa, Euphorbia heterophylla and Euphorbia hirta. The economic analysis of treatments using the Ratio Cost Value (RVC > 1) classified them in descending order: MW > H1 > H2H3 > H3 > H1H3 > H2 > H1H2. However, when the cultivated area to be weeded is expanding and labor becomes scarce, the rains are regular and abundant, manual hoeing may become tedious. In this case, the application of 3 l ha−1 of paraquat becomes an alternative to manual hoeing for farmers wishing to increase dry bean seed production. [ABSTRACT FROM AUTHOR]

SUMMARY: Weeds in agricultural settings continually adapt to stresses from ecological and anthropogenic sources, in some cases leading to resistant populations. However, consequences of repeated sub‐lethal exposure of these stressors on fitness and stress "memory" over generations remain poorly understood. We measured plant performance over a transgenerational experiment with Arabidopsis thaliana where plants were exposed to sub‐lethal stress induced by the herbicides glyphosate or trifloxysulfuron, stresses from clipping or shading in either one (G1) or four successive generations (G1–G4), and control plants that never received stress. We found that fourth‐generation (G4) plants that had been subjected to three generations of glyphosate or trifloxysulfuron stress produced higher post‐stress biomass, seed weight, and rosette area as compared to that produced by plants that experienced stress only in the first generation (G1). By the same measure, clipping and shade were more influential on floral development time (shade) and seed weight (clipping) but did not show responsive phenotypes for vegetative metrics after multiple generations. Overall, we found that plants exhibited more rapid transgenerational vegetative "stress memory" to herbicides while reproductive plasticity was stressor dependent and similar between clipping/shade and anthropogenic stressors. Our study suggests that maternal plant stress memory aids next‐generation plants to respond and survive better under the same stressors. Significance Statement: We show differential transgenerational phenotypes to different stressors over four generations in Arabidopsis. [ABSTRACT FROM AUTHOR]

Since the introduction and widespread adoption of chemical herbicides, "weed management" has become almost synonymous with "herbicide management." Over-reliance on herbicides and herbicide-resistant crops has given rise to herbicide resistant weeds. Integrated weed management (IWM) identifies three strategies for weed management— biological-cultural, chemical-technological, mechanical-physical—and recommends combining all three to mitigate herbicide resistance. However, adoption of IWM has stalled, and research to understand the adoption of IWM practices has focused on single stakeholder groups, especially farmers. In contrast, decisions about weed management often occur within a social ecosystem where multiple stakeholder groups co-create knowledge and practices. To more holistically investigate perceptions and decision-making related to herbicide resistant weed management, we conducted 23 in-depth interviews in combination with Q methodology with farmers and public-/private-sector agricultural professionals in the state of Georgia (U.S.). Our investigation focused on the management of an increasingly herbicide resistant weed, Palmer amaranth, which enabled broader conversations about agricultural systems, farmer livelihoods, and sustainability. Factor and thematic analyses allowed us to identify and characterize two distinct typologies: one primarily valued agronomic efficiency and relied upon chemical-technological management practices, while the other valued diversifying weed management strategies as the pathway to agronomic and economic success. Typologies diverged substantially in attitudes toward the three weed management strategies, the role of technology, and systems management generally. These two viewpoints have implications for how we understand underlying stakeholder motivations and choices around weed management strategies, both of which are crucial in promoting and supporting farmer use of diverse, ecologically-sound, weed management strategies. [ABSTRACT FROM AUTHOR]

One of the plantation products that is a mainstay export commodity and is considered quite strategic in supporting the Indonesian economy is tea. However, in recent years tea production has fluctuated, to keep Indonesia as the world's main tea producer, production problems and intensive efforts that support productivity need to be managed optimally. Tea quality is strongly influenced by environmental factors such as the presence of weeds. Assessment of the types of weeds in tea plants can be done by identification based on morphology. The purpose of this study was to identify weeds in tea plants (Camellia sinensis L.) in the Liki plantation unit at PT. Mitra Kerinci. This activity was carried out in July - August 2022 at PT. Mitra Kerinci, Sungai Lambai, Nagari Lubuk Gadang Selatan, Sangir District, South Solok Regency, West Sumatra Province. Observations were made using descriptive methods. It was concluded that there were 8 families and 14 species of broad-leaf weeds; 1 family and 2 species of Cyperaceae weeds; 1 family and 3 species of Poaceae weeds; and 3 families and 4 species of Filicinae weeds in this tea plantation.

A field experiment was carried out in the fall agricultural season 2023-2024 in the village of Tal Hussein, affiliated to the Hawija District in Kirkuk Governorate, and after preparing the soil by plowing and fertilizing and according to recommendations, planting was carried out on 7/14/2023 with the RAYAL (NEVADA) variety that was obtained from the markets. Local. A two-factor experiment was implemented according to a randomized complete block design (R.C.B.D.), with three sectors, each sector containing (20) experimental units. The matches between the parameters were randomly distributed, and the area of the experimental unit was (4x4) m. Each experimental unit contains (5) lines, and the space between one line and another is 75 cm, between one plant and another is 15 cm, one experimental unit and another is 50 cm, and between one repeat and another is 1.5 m. The experiment was under a sprinkler irrigation system, and the following results were obtained: The herbicides had a clear significant effect on the total number of bushes for all periods, where the Rimisulfuron + Atrazine mixture gave the lowest average on the bush number characteristic and amounted to 7.58, which did not differ from the Rimisulfuron pesticide alone, as well as a decrease in the dry weight of the bush, whether due to individual factors or interaction between the two factors, as it was recorded Rimisulfuron pesticide had the lowest average dry weight after the weedless treatment, reaching 13.50 and 0.00, respectively. As for the yield characteristics and its components, pesticides had a significant effect on most traits, especially the number of grains. A head and a weight of 300 Grain and grain yield gave the highest averages for the Rimisulfuron pesticide treatments, reaching 17.46, 644.75, and 185.00, respectively, except for grain yield, where the Atrazine pesticide treatment was

Abstract. During the period 2020-2021 the Institute for roses and aromatic plants – Kazanlak completed a field experiment on producing Rosa canina L. seedlings “Plovdiv 1” variety using herbicides. Herbicide efficiency and selectivity of flumioxazin (Pledge 50 WP) and pendimethalin (Stomp aqua) were tested. The soil herbicides were imported before pricking out Rosa canina L. seedlings. Results show that Pledge 50 WP is successfully fighting the annual species established in the experimental field (Amaranthus retroflexus L., Chenopodium album L., Polygonum aviculare L., Setaria glauca L.). Stomp aqua also shows very good results with annual weeds species leaving only 10% weeds density compared to the control. Treatment with these herbicides provides plants with healthy growing conditions for at least three months so that they can be permanently planted in autumn. No phytotoxic signs were apparent for Rosa canina L. seedlings during the whole experiment.

Many allelopathic crops are cultivated in agricultural fields, and these plants can influence the growth of other plants in the cultivation environment with their phytotoxic compounds. One of these plants is the faba bean. In this study conducted under the ecological conditions of Sakarya/Arifiye, the allelopathic effects of Eresen-87, Salkim, Bilecik, and Sakarya faba bean genotypes on weeds such as Johnson grass (Sorghum halepense L.), curly dock (Rumex crispus L.), purslane (Portulaca oleracea L.), and wild mustard (Sinapis arvensis L.) were investigated. Weed seeds used in the experiment were collected from agricultural fields in the Sakarya province. Extracts from dried plant parts of faba bean genotypes were prepared and applied to petri dishes containing weed seeds at concentrations of 5% and 10%, with four replications. At the end of the research, it was observed that all faba bean genotypes at all application doses caused a decrease in germination rate (%), root length (cm), and shoot length (cm) parameters in the four weed species tested. The best results were determined as Eresen-87 and Bilecik at 10% concentration. When the activities of fresh and dry extracts of faba bean genotypes was compared, it was determined that dry application had a higher allelopathic effect.

One of the most damaging obstacles to crop production is weeds; weeds pose a serious risk to agricultural output. Due to the homogenous morphological properties of weeds, farmers are unable to identify and classify the weed leaves.This study can aid farmers in identifying, categorizing, and quantifying the true extent of crop yield reduction. Computer vision is a sophisticated technique widely used for weed and crop leaf identification and detection in the agricultural field. This work has used three different datasets, such as 'Deep Weed', 'Crop Weed Filed Image Dataset (CWFID), and Multi-view Image Dataset for Weed Detection in Wheat Field (MMIDDWF), and collected 5090 images for training the model. This work uses segmentation techniques for vegetation and semantics for weed object detection. Furthermore, the masked image is distributed as small tiles; often the patches are square tiles, as in 25 × 25 (px), 50 × 50 (px), and 100 × 100 (px). This work has proposed a Deep Learning segmentation model named 'Pyramid Scene Parsing Network-USegNet' (PSPUSegNet) for data classification and compared the accuracy of the data from existing segmentation models such as UNet, SegNet, and USegNet. The suggested model, PSPUSegNet, obtained 96.98% precision, 97.98% recall, and 98.96% data accuracy in the Deep Weed dataset. The proposed model has self-supervised in term of deep learning mechanism.Our findings demonstrate that the deep weed dataset has achieved greater data accuracy compared to the CWFID and MMIDDWF datasets. The findings support the effectiveness of the suggested approach for weed species recognition. [ABSTRACT FROM AUTHOR]

Canada thistle is a pervasive perennial weed, causing challenges to agricultural and natural ecosystems globally. Although research has focused on the phenology, genetics, and control of Canada thistle, little is known about the rhizosphere microbiome and the role plant–microbe interactions play in invasion success. This study investigated the rhizosphere microbiome of Canada thistle across diverse climates, soils, and crops in the U.S. northern Great Plains. Soil and rhizosphere samples were collected and bacterial 16S and fungal ITS2 sequencing were performed to characterize the core microbiome and identify potential factors contributing to invasion success. Amplicon sequencing revealed a stable core microbiome that was detected in the Canada thistle rhizosphere across all locations. The core microbiome was dominated by the bacterial phyla Actinobacteriota and Proteobacteria and fungal phyla Ascomycota and Basidiomycota. Differential abundance analysis showed rhizosphere fungal communities were enriched in pathogen-containing genera with a 1.7-fold greater abundance of Fusaria and a 2.6-fold greater abundance of Gibberella compared to bulk soil. Predictive functional profiling showed rhizosphere communities were enriched (p < 0.05, FDR corrected) in plant pathogen fungal guilds which represented 19% of the fungal community. The rhizosphere microbiome was similar in composition across environments, highlighting the stable association between Canada thistle and specific microbial taxa. This study characterized the core microbiome of Canada thistle, and the findings highlight plant–microbe interactions shaping invasive behavior. These findings are important for understanding the ecological impacts of plant invasion and soil-microbe ecological processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Conyza Canadensis SHMT1 (CcSHMT1) structure was firstly resolved and a typical α-class PLP-dependent enzyme. • The dimethyl 2-acetamido terephthalate containing compounds had excellent herbicidal activity through virtual screening and biological assays. • The compound 9ay (IC 50 =193.8 g a.i./ha) exhibited the highest herbicidal efficiency and had no obvious side-effect on maize. • The first-in-class Cc SHMT1 inhibitor that could be developed as a potent herbicide with a new mode-of-action. Herbicide application is a highly efficiency method of weed control that boots agricultural output and assures food security. The development of novel herbicides focuses on improved bioactivity and new modes of action. The amino acid biosynthesis was validated as a promising novel mode of action for herbicidal compounds. However, the amino acid biosynthesis enzyme remains largely unexplored for herbicidal targets. Serine hydroxymethyl transferase (SHMT) is an essential enzyme in the photorespiratory cycle. The study aims to explore Conyza canadensis SHMT1 (Cc SHMT1) as a promising target for herbicide discovery. Structure determination of Cc SHMT1 was resolved by X-ray crystallography. Virtual screening docking experiments were performed with Glide version 5.5. Novel derivatives of dimethyl 2-acetamido terephthalate were further designed, synthesized, and bioassay. The druggability of the inhibitor was evidenced by ultrastructural changes in mitochondria, in vivo and vitro enzyme activity assays, and genetics analysis. Cc SHMT1 has a typical PLP-dependent enzyme 3D structure. The dimethyl 2-acetamido terephthalate-containing compounds had herbicidal activity. Dimethyl 2-(2-(4-(2-(4-bromo-2-chlorophenoxy) acetyl)piperazin-1-yl)acetamido) terephthalate (Compound 9ay , EC 50 = 193.8 g a.i./ ha) exhibited the highest herbicidal activity on tested weed among the synthesized compounds. Compound 9ay had no obvious adverse effect on the growth of maize and honeybees. Compound 9ay was verified to target Cc SHMT1 as an herbicide candidate. A first-in-class Cc SHMT1 inhibitor that could be developed as a potent herbicide with a new mode of action and provide an avenue for discovering novel inhibitors of pyridoxal-5-phosphate-dependent enzymes. [ABSTRACT FROM AUTHOR]

Blue heliotrope (Heliotropium amplexicaule Vahl) is an extremely drought-hardy perennial weed that is often problematic within agricultural production systems and natural environments in some parts of the world. It has the capacity to outcompete and displace desirable plant species and it contains various biochemical compounds that are toxic to grazing livestock and humans. Heliotropium amplexicaule plants can grow within a range of climatic and environmental conditions and produce seeds that remain dormant for several years within the soil which exhibit staggered emergence long after the original parent plants have expired. While control options, including biological, chemical, cultural, and physical methods, are available, many are not suitable as a single-use approach for the long-term management of this species. Therefore, an integrated weed management (IWM) program is necessary for the confident and long-term management of H. amplexicaule, particularly within dryland ecosystems. This review explores the biology, ecology, distribution, and suitable management options currently available for H. amplexicaule, while identifying research gaps that can be addressed to assist in its future management. While particular emphasis is placed on the Australian experience, information from a global perspective is included, providing valuable insights for the long-term management of H. amplexicaule worldwide. [ABSTRACT FROM AUTHOR]

The unculturable bacterium 'Candidatus Liberibacter soianacearum' (CLso) is responsible for a growing number of emerging crop diseases. However, we know little about the diversity and ecology of CLso and its psyllid vectors outside of agricultural systems, which limits our ability to manage crop disease and understand the impacts this pathogen may have on wild plants in natural ecosystems. In North America, CLso is transmitted to crops by the native potato psyllid (Bactericera cockerelli). However, the geographic and host plant range of the potato psyllid and CLso beyond the borders of agriculture are not well understood. A recent study of historic herbarium specimens revealed that a unique haplotype of CLso was present infecting populations of the native perennial Solanum umbelliferum in California decades before CLso was first detected in crops. We hypothesized that this haplotype and other potentially novel CLso variants arc still present in S. umbelliferum populations. To test this, we surveyed populations of S'. umbelliferum in Southern California for CLso and potato psyllid vectors. We found multiple haplotypes of CLso and the potato psyllid associated with these populations, with none of these genetic variants having been previously reported in California crops. These results suggest that CLso and its psyllid vectors are much more widespread and diverse in North American natural plant communities than suggested by data collected solely from crops and weeds in agricultural fields. Further characterization of these apparently asymptomatic haplotypes will facilitate comparison with disease-causing variants and provide insights into the continued emergence and spread of CLso. [ABSTRACT FROM AUTHOR]

Field bindweed (Convolvulus arvensis L.) is an important weed species in agricultural areas in Türkiye and worldwide. The study, conducted in 2018-2019, involved collecting seeds from 16 different provinces in Türkiye (Adana, Ankara, Çanakkale, Denizli, Diyarbakır, Erzurum, Hatay, İzmir, Karaman, Kayseri, Konya, Malatya, Samsun, Şanlıurfa, Tekirdağ and Uşak). These seeds were then germinated under greenhouse conditions (29/19°C day/night), and molecular characterization of the samples was performed. As a result of comparing the samples with a specific reference from NCBI GenBank, it was found that the similarity ratios were close to each other but formed different groups. The study revealed that samples from Adana, Konya and Samsun belonged to different groups in terms of similarity. Subsequently, the dose-response rates of these samples to 2,4-D, a herbicide licensed against field bindweed, were determined. In the dose-response analysis of the herbicides, ED50 values of 131.93, 115.42 and 141.89 g.a.i/ha were determined for Adana, Konya and Samsun, respectively. The study concluded that the dose-response of field bindweed in Adana, Konya and Samsun provinces, belonging to different molecular groups, to 2,4-D herbicide is close to each other but exhibits different values. [ABSTRACT FROM AUTHOR]

The species composition of vegetation in field manure piles is significant in terms of weed spread via farmyard manure. For the purpose of vegetation assessment, 12 manure piles were selected in different regions of Moravia (Czech Republic). During the mapping of the manure piles vegetation, 89 weed species were found. Among the species with dominant representation are: Chenopodium album subsp. album, Atriplex sagittata, Echinochloa crus-galli, Amaranthus retroflexus, Tripleurospermum inodorum, Polygonum aviculare. Specific conditions of the field manure piles create a unique selective pressure that allows only certain weed species to survive. The species composition of weed vegetation in the manure piles indicates high availability of nitrogen and phosphorus. The excess of nutrients creates conditions for the production of a large number of fruits and weed seeds in manure fields. The observed manure field piles were dominated by weed species with long persistence of their seeds in the soil. The vegetation of field manure piles is considered the primary source of weed seeds in manure and plays a significant role in the spread of weeds in agricultural landscapes. [ABSTRACT FROM AUTHOR]

Capitalizing on the widespread adoption of smartphones among farmers and the application of artificial intelligence in computer vision, a variety of mobile applications have recently emerged in the agricultural domain. This paper introduces GranoScan, a freely available mobile app accessible on major online platforms, specifically designed for the real-time detection and identification of over 80 threats affecting wheat in the Mediterranean region. Developed through a co-design methodology involving direct collaboration with Italian farmers, this participatory approach resulted in an app featuring: (i) a graphical interface optimized for diverse in-field lighting conditions, (ii) a user-friendly interface allowing swift selection from a predefined menu, (iii) operability even in low or no connectivity, (iv) a straightforward operational guide, and (v) the ability to specify an area of interest in the photo for targeted threat identification. Underpinning GranoScan is a deep learning architecture named efficient minimal adaptive ensembling that was used to obtain accurate and robust artificial intelligence models. The method is based on an ensembling strategy that uses as core models two instances of the EfficientNet-b0 architecture, selected through the weighted F1-score. In this phase a very good precision is reached with peaks of 100% for pests, as well as in leaf damage and root disease tasks, and in some classes of spike and stem disease tasks. For weeds in the post-germination phase, the precision values range between 80% and 100%, while 100% is reached in all the classes for pre-flowering weeds, except one. Regarding recognition accuracy towards end-users in-field photos, GranoScan achieved good performances, with a mean accuracy of 77% and 95% for leaf diseases and for spike, stem and root diseases, respectively. Pests gained an accuracy of up to 94%, while for weeds the app shows a great ability (100% accuracy) in recognizing whether the target weed is a dicot or monocot and 60% accuracy for distinguishing species in both the post-germination and pre-flowering stage. Our precision and accuracy results conform to or outperform those of other studies deploying artificial intelligence models on mobile devices, confirming that GranoScan is a valuable tool also in challenging outdoor conditions. [ABSTRACT FROM AUTHOR]

In the intricate web of plant–animal interactions, granivore birds can play a dual antagonist–mutualist role as seed predators and dispersers. This study delves into the ecological significance of the house sparrow (Passer domesticus) as seed disperser by endozoochory. A sample of individual droppings and faecal pools were collected from a communal roost in central Spain to examine the presence of seeds. Seed viability was determined using the tetrazolium test. Our findings revealed that around 22% of the analysed droppings contained seeds, contradicting the prevalent notion of house sparrow solely as seed predator. Viability tests demonstrated that 53.9% of the defecated seeds were viable, although it varied between plant species, including those from fleshy‐fruited common fig and five species of dry‐fruited herbs. This study challenges the traditional perspectives on the ecological role of the house sparrow, and glimpses on their contribution to seed dispersal. Understanding the nuanced roles of granivore species like the house sparrow is crucial for developing holistic conservation and management strategies in urban and agricultural landscapes. Future studies are encouraged to unravel the actual role of this cosmopolitan species as disperser of a likely broad spectrum of wild, cultivated and exotic plants. [ABSTRACT FROM AUTHOR]

Background: Maize, being highly productive and versatile cereal crop, is influenced by various biotic and abiotic stresses. Among biotic stresses, weed infestation is one of the serious concerns in maize cultivation. Weeds can affect maize by competing for light, water and nutrients resulting in yield loss of up to 70% in severe cases. Methods: A field experiment was conducted during kharif season for two consecutive years of 2019 and 2020 in agriculture farm of Palli Siksha Bhavana (Institute of Agriculture), Visva-Bharati, Sriniketan, West Bengal, India. The experiment was laid out in randomized block design and replicated thrice. The experiment comprised of seven weed management treatments viz. T1 (tembotrione 9% + atrazine 45% WG @ 1000 g/ha), T2 (tembotrione 9% + atrazine 45% WG @ 1250 g/ha), T3 (tembotrione 9% + atrazine 45% WG @ 1500 g/ha), T4 (Tembotrione 34.4% SC @ 286 ml/ha), T5 (Atrazine 50% WP), T6 (Hand weeding), T7 (Weedy check). Result: Experimental results revealed that among different herbicide mixtures, tembotrione + atrazine 1500 g/ha was found to be effective in suppressing the weeds growth and found no residual effect on soil chemical and biological properties during both the years of the experiment. [ABSTRACT FROM AUTHOR]

Waterhemp (Amaranthus tuberculatus (Moq.) Sauer) is one of the most problematic weeds in the Midwestern agricultural systems in the USA. As a consequence of extensive herbicide selection pressure, many waterhemp populations across the USA evolved resistance to multiple herbicides, leading to limited options for chemical control. Genome editing tools, including CRISPR/Cas9, have great potential in weed science, especially when coupled with a gene drive system for a sustainable weed management. The application of modern biotechnological tools requires availability of an efficient regeneration and genetic transformation system. The objectives of this research were to develop an efficient protocol for successful regeneration of waterhemp via callus culture and optimize an Agrobacterium-mediated transformation method for waterhemp. Hypocotyl explants cultured on callus induction medium (CIM), C6 containing 1.0 mg L−1 kinetin and 4.0 mg L−1 2,4-D for 2 wk followed by subculture into shoot induction medium (SIM), S8 containing 3.0 mg L−1 BAP, 0.05 mg L−1 2,4-D, and 0.3 mg L−1 GA3 for 4 to 6 wk was successful in shoot regeneration. Leaf explants failed to respond to any treatment combinations tested for regeneration. Using the hypocotyl explant–based regeneration protocol optimized in this research, Agrobacterium-mediated transformation was performed using uidA and hpt genes as a proof of concept. Although transgenic plants were not regenerated, molecular characterization of the transformed calluses confirmed the presence of transgenic genes, for example uidA and hpt. This is the first report of the tissue-cultured-based regeneration and Agrobacterium-mediated transformation of hypocotyl derived calluses in waterhemp, which is a step forward in exploring the possibilities of genome editing research in weed science. [ABSTRACT FROM AUTHOR]

Canary grass (Phalaris canariensis L.) is a versatile crop with global significance; it is primarily cultivated for its small elliptical seeds, which are used as bird feed and for human consumption. This crop is adapted to various climates and soils, so it can be grown successfully in Hungary. However, challenges such as weed control, climate change impacts, and soil factors require strategic management for sustained success in canary grass cultivation. Our study investigated the impact of management and environmental (as seasonal and soil) factors on pre-harvest weed vegetation in canary grass fields in Southeast Hungary between 2017 and 2020. In addition to showing the weed vegetation of the canary grass, the aim of our work was to promote more effective weed management of canary grass by revealing correlations between soil, seasonality, and management variables, influencing weed diversity and coverage. Using the analysis of covariance (ANCOVA) and correlation tests, we tested significant variables, providing insights into the complex interactions affecting weed composition. A redundancy analysis (RDA) further unveiled the relationships between explanatory variables and weed species' composition. The findings offer valuable information for effective weed management strategies in canary grass cultivation. Our comprehensive study on canary grass fields in Southeast Hungary sheds light on significant factors influencing weed composition and abundance. The average weed coverage was 10.8%, with summer annuals and creeping perennials being the most prevalent life forms. Echinochloa crus-galli, Cirsium arvense, Xanthium italicum, and Setaria viridis were among the dominant species. ANCOVAs revealed the impact of soil, management, and seasonal factors on weed cover, species richness, diversity, and yield levels. Soil properties like texture, pH, and nitrogen content showed varying effects on weed parameters. The vintage effect, tillage systems, and farming practices also played crucial roles. The redundancy analysis highlighted the influence of the year, soil sulfur content, and winter preceding crops on weed composition. In conclusion, the herbaceous vegetation in the studied area is dominated by summer germinating and creeping perennial species. Despite slight differences in average coverage and occurrence, a well-defined set of significant species is evident. Multicollinearity among variables suggests limitations to further increase the number of variables that can be included in the analysis. The ANCOVAs showed that the soil, seasonal, and farming variables significantly influence overall weed vegetation and crop yield, with a lesser impact on species richness and diversity. The reduced RDA model highlights the strong influence of the year on species' composition, emphasizing the inherent factors during canary grass cultivation that are challenging to modify through farming practices. [ABSTRACT FROM AUTHOR]

Weedy rice, a pervasive and troublesome weed found across the globe, has often evolved through fertilization of rice cultivars with little importance of crop‐weed gene flow. In Argentina, weedy rice has been reported as an important constraint since the early 1970s, and, in the last few years, strains with herbicide‐resistance are suspected to evolve. Despite their importance, the origin and genetic composition of Argentinian weedy rice as well its adaptation to agricultural environments has not been explored so far. To study this, we conducted genotyping‐by‐sequencing on samples of Argentinian weedy and cultivated rice and compared them with published data from weedy, cultivated and wild rice accessions distributed worldwide. In addition, we conducted a phenotypic characterization for weedy‐related traits, a herbicide resistance screening and genotyped accessions for known mutations in the acetolactate synthase (ALS) gene, which confers herbicide resistance. Our results revealed large phenotypic variability in Argentinian weedy rice. Most strains were resistant to ALS‐inhibiting herbicides with a high frequency of the ALS mutation (A122T) present in Argentinian rice cultivars. Argentinian cultivars belonged to the three major genetic groups of rice: japonica, indica and aus while weeds were mostly aus or aus‐indica admixed, resembling weedy rice strains from the Southern Cone region. Phylogenetic analysis supports a single origin for aus‐like South American weeds, likely as seed contaminants from the United States, and then admixture with local indica cultivars. Our findings demonstrate that crop to weed introgression can facilitate rapid adaptation to agriculture environments. [ABSTRACT FROM AUTHOR]