Search Results (125)

Chickpea is a highly weed-prone crop with limited herbicide options and high labor demands, raising the following question: Can fall-planted legume–cereal cover crops (CCs) improve soil properties while reducing herbicide use and manual weeding pressure? To explore this, we evaluated the effect of fall-planted winter rye (WR) alone in 2021 and mixed with hairy vetch (HV) in 2022 and 2023 at Randolph farm in Petersburg, Virginia. The objectives were two-fold: (a) to examine the effect of CCs on soil properties using monthly growth dynamics and biomass harvested from fifteen 0.25 m²-quadrants and (b) to evaluate the efficiency of five termination methods: (1) green manure (GM); (2) GM plus pre-emergence herbicide (GMH); (3) burn (BOH); (4) crimp mulch (CRM); and (5) mow-mulch (MW) in suppressing weeds in chickpea fields. Weed distribution, particularly nutsedge, was patchy and dominant on the eastern side. Growth dynamics followed an exponential growth rate in fall 2022 (R² ≥ 0.994, p < 0.0002) and a three-parameter sigmoidal curve in 2023 (R² ≥ 0.972, p < 0.0047). Biomass averaged 55.8 and 96.9 t/ha for 2022 and 2023, respectively. GMH consistently outperformed GM in weed suppression, though GM was not significantly different from no-till systems by the season’s end. Kabuli-type chickpeas under GMH had significantly higher yields than desi types. Pooled data fitted well to a three-parametric logistic curve, predicting half-time to 50% weed coverage at 35 (MM), 38 (CRM), 40 (BOH), 46 (GM), and 53 (GMH) days. Relapses of CCs were consistent in no-till systems, especially BOH and MW. Although soil properties improved, CCs alone did not significantly suppress weed. Full article

Weeds pose a significant challenge to agricultural productivity, requiring control strategies that are both effective and environmentally sustainable. Therefore, this study evaluated the inhibitory potential of aqueous extracts from Ricinus communis L. leaves to manage the weeds Oryza sativa L. (weedy rice) and Cyperus ferax. Extracts were obtained through pressurized liquid extraction using water as the solvent. Bioassays were conducted during pre- and post-emergence stages by foliar spraying 15 and 30 days after sowing (DAS). The effect of extraction time (1–30 min) on inhibitory efficacy was also assessed. Chemical profiles of the extracts were characterized using high-performance liquid chromatography. The extracts significantly inhibited seed germination, with suppression rates reaching 92.7%. Plant growth was also diminished, particularly with earlier treatments (at 15 DAS), resulting in reductions of up to 32% and 53% in shoot length, and 69% and 73% in total dry mass for O. sativa L. and C. ferax, respectively. Mortality rates of O. sativa L. and C. ferax reached 64% and 58%, respectively. Phenolic compounds were identified in the extracts, and higher concentrations were observed at shorter extraction times. These findings underscore the potential of R. communis L. leaf extracts as an ecologically sustainable alternative for weed management, providing an effective and natural approach that may reduce reliance on synthetic herbicides and mitigate their environmental impact. Full article

Accurate crop row detection is crucial for determining weed pressure (weeds item per square meter). However, this task is complicated by the similarity between crops and weeds, the presence of missing plants within rows, and the varying growth stages of both. Our hypothesis was that in drone imagery captured at altitudes of 20–30 m—where individual plant details are not discernible—weed presence among crops can be statistically detected, allowing for the generation of a weed distribution map. This study proposes a computer vision detection method using images captured by unmanned aerial vehicles (UAVs) consisting of six main phases. The method was tested on 208 images. The algorithm performs well under normal conditions; however, when the weed density is too high, it fails to detect the row direction properly and begins processing misleading data. To investigate these cases, 120 artificial datasets were created with varying parameters, and the scenarios were analyzed. It was found that a rate variable—in-row concentration ratio (IRCR)—can be used to determine whether the result is valid (usable) or invalid (to be discarded). The F1 score is a metric combining precision and recall using a harmonic mean, where “1” indicates that precision and recall are equally weighted, i.e., β = 1 in the general Fβ formula. In the case of moderate weed infestation, where 678 crop plants and 600 weeds were present, the algorithm achieved an F1 score of 86.32% in plant classification, even with a 4% row disturbance level. Furthermore, IRCR also indicates the level of weed pressure in the area. The correlation between the ground truth weed-to-crop ratio and the weed/crop classification rate produced by the algorithm is 98–99%. As a result, the algorithm is capable of filtering out heavily infested areas that require full weed control and capable of generating weed density maps on other cases to support precision weed management. Full article

Echinochloa spp. are among the most problematic malignant weeds in paddy fields. Under long-term herbicide selection pressure, they have developed resistances to multiple herbicides, leading to diminished control efficacy. Precision herbicide application, tailored to the susceptibility disparities among Echinochloa species, has emerged as a promising strategy to enhance weed control efficacy and decelerate herbicide resistance development. Nevertheless, the herbicide susceptibility variation across different Echinochloa taxa remain uncharted. Therefore, in this study, we determined the susceptibility of five Echinochloa species to 15 commonly used herbicides using the whole-plant bioassay method. Additionally, we explored the feasibility of employing the CDDP molecular marker technique for the rapid identification of distinct Echinochloa species. The results showing that five Echinochloa species exhibited differential susceptibility to 12 of the 15 herbicides tested underscore the necessity of personalized herbicide application strategies. Among the seven CDDP markers, KNOX-3 generated a specific band in the Echinochloa caudata population, which can be used to distinguish it from the other four Echinochloa species. The findings of this study will facilitate the precision application of herbicides for Echinochloa management in paddy fields. Full article

This study evaluated the application of the aqueous extract from Baccharis trimera (Less) DC. in the control of weed species Oryza sativa L. and Cyperus ferax Rich. during the germination and early development stages. Extracts were obtained through pressurized liquid extraction using kinetic assays. Shorter extraction times (1 to 10 min) showed extracts with higher inhibitory effects on seed germination, shoot and root lengths, and fresh and dry mass of the plants. The survival of treated plants was also affected, especially during the early stages of development, reaching up to 40% of mortality. HPLC analysis identified phenolic compounds such as ferulic acid, rutin, quercitrin, and quercetin, with higher concentrations found in the extracts obtained at shorter times of extraction. The reduction in these compounds over longer extraction times was correlated with decreased inhibitory activity. The results indicate that the aqueous extract of B. trimera (Less) DC. holds potential for ecological weed management, standing out as a viable alternative to reduce weed resistance to synthetic herbicides. Full article

Agricultural water resource management is increasingly challenged by climate variability, land degradation, and socio-economic pressures, particularly in the Mediterranean region. This study, conducted in 2023–2024 within the REACT4MED project (PRIMA initiative), addresses sustainable water use through a comparative analysis of organic and conventional farms in the Stornara and Tara area (Puglia, Italy). The research aimed to identify critical indicators for sustainable water management and develop ecosystem restoration strategies that can be replicated across similar Mediterranean agro-ecosystems. An interdisciplinary, participatory approach was adopted, combining technical analyses and stakeholder engagement through three workshops involving 30 participants from diverse sectors. Fieldwork and laboratory assessments included soil sampling and analysis of parameters such as pH, electrical conductivity, soil organic carbon, nutrients, and salinity. Cartographic studies of vegetation, land use, and pedological characterization supplemented the dataset. The key challenges identified were water loss in distribution systems, seawater intrusion, water pumping from unauthorized wells, and inadequate public policies. Soil quality was significantly influenced by salt stress, hence affecting crop productivity, while socio-economic factors affected farm income. Restoration strategies emphasized the need for water-efficient irrigation, less water-intensive crops, and green vegetation in infrastructure channels while incorporating also the native flora. Enhancing plant biodiversity through weed management in drainage channels proved beneficial for pathogen control. Proposed socio-economic measures include increased inclusion of women and youth in agricultural management activities. Integrated technical and participatory approaches are essential for effective water resource governance in Mediterranean agriculture. This study offers scalable, context-specific indicators and solutions for sustainable land and water management in the face of ongoing desertification and climate stress. Full article

Arctium lappa L., commonly known as burdock, is a biennial plant whose roots are a valuable source of bioactive phenolic compounds with notable health-promoting properties. However, the bioactivity of these compounds is influenced by both extraction parameters and plant growth conditions. This study investigated the combined effect of extraction temperature, land management, and cultivation altitude on the antioxidant and anticholinergic potential of burdock root extracts obtained through pressurized liquid extraction (PLE). Extractions were performed at 50 °C, 100 °C, and 150 °C, with 50 °C being the temperature that best preserved phenolic content and bioactivity. Remarkably, root extracts obtained at 50 °C and collected from an untreated organic field at 150 m altitude yielded higher phenolic levels (42 mg gallic acid/g extract) than conventional solid–liquid extraction (38 mg gallic acid/g extract). A comparative analysis of three ecotypes, including Organic Land Ecotype (OLE) and Spontaneous Land Ecotype (SPLE), both collected at 150 m altitude, and Spontaneous Mountain Ecotype (SPME), collected at 800 m (over sea level), revealed that a higher altitude significantly increased phenolic content and anticholinergic potential. Furthermore, roots from non-weeded soils exhibited superior bioactivity compared to those from weeded areas. These findings underline that the successful obtention of highly bioactive burdock root extracts depends not only on extraction conditions, but also critically on cultivation altitude and land management strategies. Full article

Soybean–maize intercropping is a traditional yet high-yield cultivation model that faces technical challenges in weed management due to the different herbicide requirements of soybean and maize. This study presents the design and experiments of the innovative dual-herbicide direct injection system, which can simultaneously deliver glyphosate and fomesafen through real-time concentration modulation. The system operates by measuring the relationship between the mixing ratio and the conductivity value, mathematical model, and control algorithm. Experimental validation demonstrated that the correlation coefficient of herbicide mixing ratios and measured conductivity values across pressure ranges of 0.1–0.3 MPa are greater than 0.98, which means that measuring the mixing ratio using conductivity is reliable. Optimal operational performance was achieved at 0.2 MPa spraying pressure, characterized by superior mixing uniformity (CV < 5%) and system stability. This technological advancement provides a practical solution for precision agrochemical application in complex cropping models, with potential applications extending to other crop combinations requiring differential herbicide treatments. Full article

Armillaria root rot (ARR) is a fungal disease caused by Desarmillaria caespitosa and the leading cause of peach tree decline in the Southeastern U.S. It affects the roots and lower stems of trees, leading to the decay of the tree’s root system. Planting peach trees shallow on berms and excavating soil around the root collar after two years can extend the economic life of infected trees. However, berms pose operational challenges, including elevation changes, soil erosion from water flow, and herbicide and fertilizer runoff, thereby reducing orchard management efficiency. This study aimed to develop a tractor-mounted rotary tillage method to flatten the area between peach trees planted on berms, improving safety and reducing runoff. A custom paddle wheel attachment (20.3 cm height, 30.5 cm length) was retrofitted to an existing mechanical orchard weed management implement equipped with a hydraulic rotary head. A hydraulic flow meter, two pressure transducers, and an RTK-GPS receiver were integrated with a wireless data acquisition system to monitor the paddle wheel rotational speed and tractor ground speed during field trials. The effects of three paddle wheel speeds (132, 177, and 204 RPM) and three tractor ground speeds (1.65, 2.255, and 3.08 km/h) were evaluated in two orchards with Cecil sandy loam soil (bulk density: 1.93 g/cm³; slope: 2–6%). The paddle wheel speed had a greater influence on the torque and power requirements than the tractor ground speed. The combination of a 177 RPM paddle speed and 3 km/h tractor speed resulted in the smoothest soil surface with minimum torque demand, indicating this setting as optimal for flattening berms in similar soil conditions. Future research will include optimizing the paddle wheel structure and equipping the berm leveling machine with tree detection sensors to control the rotary head position. Full article

The continued emergence of weedy rice (Oryza sativa L.) in Taiwan poses serious challenges to seed purity and commercial rice cultivation, particularly under transplanting systems. These off-type individuals, often marked by a red pericarp, reduce varietal integrity and complicate seed propagation. This study evaluated the morphological variation among 117 Taiwan weedy rice (TWR) accessions and 55 control cultivars, which include 24 temperate japonica cultivars (TEJ), 24 indica cultivars, and seven U.S. weedy rice (UWR) types. Principal component analysis (PCA) showed that TWR shares vegetative traits with modern cultivars but exhibits grain morphology resembling indica landraces—indicating weak artificial selection pressure on grain traits during nursery propagation. TWR was also found to possess a suite of adaptive weedy traits, including semi-dwarfism, delayed heading, high shattering, and superior seed storability, facilitating its persistence in field conditions. These findings provide critical insights for integrated weed management and cultivar purity strategies, emphasizing the importance of certified seed use, stringent field hygiene, and disruption of weedy rice reproductive cycles. Full article

Weed control is fundamental to modern agriculture, underpinning crop productivity, food security, and the economic sustainability of farming operations. Herbicides have long been the cornerstone of effective weed management, significantly enhancing agricultural yields over recent decades. However, the field now faces critical challenges, including stagnation in the discovery of new herbicide modes of action (MOAs) and the escalating prevalence of herbicide-resistant weed populations. High research and development costs, coupled with stringent regulatory hurdles, have impeded the introduction of novel herbicides, while the widespread reliance on glyphosate-based systems has accelerated resistance development. In response to these issues, advanced image-based plant phenotyping technologies have emerged as pivotal tools in addressing herbicide-related challenges in weed science. Utilizing sensor technologies such as hyperspectral, multispectral, RGB, fluorescence, and thermal imaging methods, plant phenotyping enables the precise monitoring of herbicide drift, analysis of resistance mechanisms, and development of new herbicides with innovative MOAs. The integration of machine learning algorithms with imaging data further enhances the ability to detect subtle phenotypic changes, predict herbicide resistance, and facilitate timely interventions. This review comprehensively examines the application of image phenotyping technologies in weed science, detailing various sensor types and deployment platforms, exploring modeling methods, and highlighting unique findings and innovative applications. Additionally, it addresses current limitations and proposes future research directions, emphasizing the significant contributions of phenotyping advancements to sustainable and effective weed management strategies. By leveraging these sophisticated technologies, the agricultural sector can overcome existing herbicide challenges, ensuring continued productivity and resilience in the face of evolving weed pressures. Full article

Eragrostis plana is an invasive plant in horticulture that is extremely difficult to control. The use of chemical herbicides causes weed resistance and contamination of crops. Therefore, leaf extracts obtained from E. camaldulensis, C. barbatus, and L. leucocephala were evaluated in the control of this weed. The extracts were obtained from leaves by infusion, pressurized liquid extraction, and ultrasound-assisted extraction using water or ethanol as solvents, which are green methods. The phytochemicals from E. camaldulensis and C. barbatus reduced the germination and growth of the weed, reaching up to 97% inhibition of germination, 52% reduction in shoot length, and 46% reduction in root length for the germinated seeds. Full article

This study introduces a novel pressurized liquid extraction (PLE) strategy utilizing biobased solvents to simultaneously extract non-polar and polar compounds with antioxidant and anticholinergic properties from burdock roots. The influence of altitude and weeding on the bioactive composition of three burdock root ecotypes was evaluated: two from 150 m (one subjected to weeding during growth and another not subjected to weeding) and one from 800 m without weeding. A simplex-centroid mixture design identified 100% 2-methyltetrahydrofuran as the optimal solvent for PLE, offering superior extraction of bioactive compounds due to its ability to form strong hydrogen bonds with phenolic groups. Extraction at 100 °C was found to be optimal, avoiding the low yields and undesirable reactions observed at 40 °C and 160 °C, respectively. Altitude emerged as the most significant factor influencing bioactivity and composition, with roots from 800 m exhibiting the highest bioactivity. Key bioactive compounds included caffeoylquinic acids, caryophyllene oxide, spathulenol, and bisnorallocholanic acid. At 150 m, weeding reduced anticholinergic capacity but increased antioxidant synthesis, though the levels were lower than those observed at higher altitudes. These findings highlight that burdock roots grown at high altitudes without weeding produce extracts rich in antioxidant and neuroprotective compounds, offering significant potential for functional ingredient development. Full article

Amaranthus, a genus in Amaranthaceae, is divided into three subgenera—Amaranthus, Acnida, and Albersia—and contains approximately 70 to 80 species. Understanding its phylogenetic relationships is essential for species classification, genetic diversity assessment, and evolutionary studies. This knowledge is vital for improving Amaranthus utilization in crop improvement and managing the ecological impacts of invasive weeds. In this study, we analyzed the chloroplast genomes of 27 Amaranthus species across all three subgenera to characterize their genomic features and construct a comprehensive phylogenetic tree. Our aim was to elucidate the phylogenetic relationships within the genus and evaluate interspecific affinities among the subgenera. We also addressed the taxonomic ambiguity surrounding A. bouchonii and A. powellii to determine their distinct species within the genus. Chloroplast genome sizes ranged from 149,949 to 150,818 bp, with GC content varying between 36.52% and 36.63%. Comparative structural analyses confirmed highly conserved quadripartite structures, gene content, and organization, comprising 87 protein-coding genes, 37 tRNAs, and 8 rRNAs. Repeat and codon usage analyses revealed conserved repeat patterns and a preference for codons ending in A or U. Selection pressure analysis indicated a predominantly purifying selection, with matK showing signs of positive selection, particularly in A. spinosus. Phylogenetic analysis of 80 protein-coding genes confirmed the monophyly of subgenus Amaranthus but found Alberisa and Acnida to be paraphyletic. Despite their morphological similarity, A. bouchonii and A. powellii were placed in separate clades within subgenus Amaranthus, with A. bouchonii clustering with A. retroflexus, and A. powellii aligning with the A. hybridus complex. Additionally, we identified 16 variable regions as potential molecular markers for species identification. Our study provides the most comprehensive Amaranthus chloroplast genome dataset to date, offering new insights into its evolutionary relationships and valuable genomic resources for taxonomy, germplasm management, and invasive risk assessment. Full article

Mangrove ecosystems are globally significant for their biodiversity and ecosystem services but face persistent threats from invasive species and anthropogenic disturbances. This study investigates the interactions between Cyperus rotundus, a widespread invasive weed, and fungal communities in the mangrove-adjacent wetlands of Isla Santay, Ecuador. Using metagenomic sequencing of the ITS region, we analyzed fungal diversity in samples from an anthropogenically pressured area and a non-impacted site. Results revealed significant differences in microbial assemblages: the rhizosphere sample from the disturbed area exhibited lower fungal richness and was dominated by Magnaporthaceae (9%) and Aureobasidium melanogenum (5%), both associated with stress-tolerant traits. In contrast, the rhizosphere sample from the non-impacted site showed higher species diversity, with Cladosporium dominicanum (62%) and Talaromyces (11%) as dominant endophytic taxa. Principal Coordinates Analysis (PCoA) and co-occurrence networks highlighted distinct fungal partitioning between the two sample tissues, indicating that C. rotundus mediates microbial composition in response to environmental gradients. These findings underscore the role of microbial communities in the plant’s invasive success and suggest that leveraging beneficial fungi could enhance ecosystem resilience and support wetland restoration. By integrating molecular approaches with ecological insights, this work contributes to a deeper understanding of microbial dynamics in coastal wetlands and informs targeted management strategies to preserve mangrove habitats. Full article