Weed Research Articles

Efficacy mixture of fomesafen and clomazone for weed control in potato

In 2022–2023 in Leningrad region at potato Liga variety trials were conducted to evaluate mixture of herbicides Nexus (240 g/l of fomesafen) and Traser (480 g/l of clomazone) in the following schedules: 1.0 l/ha + 0.25 l/ha; 1.0 l/ha + 0.5 l/ha; 1.25 l/ha + 0.25 l/ha and 1.25 l/ha + 0.5 l/ha. The use of herbicides in their pure form acted as standard. The experiments were carried out in accordance with the methods of herbicide registration trials (2013; 2020). The use of tank-mix of herbicides Nexus + Traser made it possible to most fully control of mixed type of weediness, typical for the North-Western region. When applying a tank-mix herbicides in the regulations of 1.0…1.25 l/ha + 0.5 l/ha, the decrease in the weight of annual dicotyledonous weeds was at a level exceeding 75.0 %; the decrease in the weight of annual cereal weeds reached 88.3 %. The use of the herbicide Nexus in its pure form was most noticeably inferior to the application of tank-mix of herbicides Nexus + Traser (1.0…1.25 l/ha + 0.5 l/ha) in terms of effect on plants of barnyard grass (Echinochloa crusgalli (L.) Beauv.)) and baconweed (Chenopodium album L.). The main advantage of a tank-mix of herbicides over the herbicide Traser in its pure form was realized in relation to the effect on pale persicaria (Polygonum lapathifolium L.). Reduced competition from weeds contributed to the preservation of potato yields of Liga variety cultivated in the North-Western region. Under normal moisture conditions, the potato yield after using a tank-mix of herbicides Nexus and Traser (31.0…35.8 t/ha) significantly exceeded the crop yield after using these herbicides in their pure form (17.5…23.3 t/ha).

Opportunities and Challenges on Natural Farming

Natural Farming, an ecological and sustainable agricultural practice, emphasizes minimal human intervention and the use of natural resources for crop cultivation. Unlike conventional farming, which relies heavily on chemical inputs, Natural Farming integrates practices such as minimal tillage and organic inputs like cow dung and plant-based preparations. This case study explores Natural Farming practices among farmers in Tamil Nadu, focusing on their experiences, opportunities, and challenges. The study includes detailed case studies of three farmers in Coimbatore District and each farmer employing different natural farming techniques and facing unique obstacles. The findings reveal that Natural Farming offers significant benefits, including reduced farming costs, improved soil health, and enhanced market opportunities for organic produce. Farmers reported that these practices lead to better crop resilience and higher-quality produce, often fetching premium prices. However, challenges persist, including difficulties in weed control, pest and disease management, labor shortages, and delay in certification, which can affect market access and profitability. The study underscores the potential of Natural Farming to transform agricultural practices by promoting sustainability and reducing dependence on chemical inputs. It also highlights the need for supportive interventions, such as enhanced market access, comprehensive farmer training, and government support to address the identified challenges and maximize the benefits of Natural Farming. This study contributes to a deeper understanding of Natural Farming's role in sustainable agriculture and its implications for farmers in Tamil Nadu.

Efficacy of Pre and Post Emergence Herbicides against Complex Weed Flora, Yield and Economics of Blackgram under High Hills Wet Temperate Zone of Himachal Pradesh

Background: Implementing integrated strategies for weed management is essential in maximizing blackgram yield. Unchecked weed proliferation leads to substantial decrease in crop productivity. Methods: The current field experiment was conducted at Salooni, Himachal Pradesh, to evaluate the efficacy of different integrated weed management practices during Kharif 2022 and 2023. Eleven treatments targeting weed control were evaluated both at pre and post - emergence stages. Result: The predominant weeds were Echinochloa colona, Galinsoga parviflora, Cyperus species and other broad leaf weeds were Plantago lanceolata, Trifolium repens, Trianthema species, Ageratum conyzoides. Data on weed dynamics revealed that; after weed-free treatment, the application of Imazethapyr 75 g/ha as PE fb HW at 30 DAS; Pendimethalin 1.0 kg/ha as PE fb HW at 30 DAS and Pendimethalin 1.0 kg/ha + imazethapyr 75 g/ha (PE) recorded a significantly lower total weed count as compared to other treatments. Parameters related to blackgram growth and yield, including plant height, number of branches per plant, pods per plant, grain yield and haulm yield were significantly higher with weed-free treatment followed by application of imazethapyr 75 g/ha as PE fb HW at 30 DAS, remaining at par with application of pendimethalin 1.0 kg/ha + imazethapyr 75 g/ha (PE) and pendimethalin 1.0 kg/ha as PE fb HW at 30 DAS. The most economically efficient weed control method was the combination of pendimethalin 1.0 kg/ha + imazethapyr 75 g/ha (PE), as it resulted in the highest net returns and marginal benefit-cost ratio.

A comparative study of drone and manual herbicide application for weed management in wet direct-seeded rice (Oryza sativa L.)

A field experiment was conducted at Tamil Nadu Agricultural University, Coimbatore, during the Navarai season (January-April) of 2024 to assess the efficiency of drone-based herbicide application in terms of weed control, energy use, and cost effectiveness in wet direct-seeded rice (Oryza sativa L.). The study compared the effectiveness of weed control using herbicide combinations applied as pre-emergence followed by early post-emergence, with both drone and knapsack sprayer. The treatments included the application of pretilachlor followed by early post-emergence bispyribac sodium, and pyrazosulfuron followed by penoxsulam + cyhalofop butyl, using both drone and knapsack sprayer. Additionally, weed-free and unweeded control plots were included. Results indicated that the application of pretilachlor followed by bispyribac sodium using a drone sprayer significantly reduced weed density and weed dry weight compared to the unweeded plot. This treatment also resulted in a higher grain yield (5286 kg ha-1). Moreover, drone application of pretilachlor followed by bispyribac sodium provided a higher net return (? 51631/ha), benefit-cost ratio (2.17), energy-use efficiency (9.53), and energy productivity (0.30 kg/MJ). The experiment concluded that drone-based spraying of pretilachlor followed by bispyribac sodium is an effective weed management strategy for wet direct-seeded rice, offering superior yield attributes, energy use efficiency, and profitability.

Weed management in organic dryland wheat production in the Pacific Northwest

AbstractGrowth in demand for organic small grains has increased interest in producing certified organic crops in the semiarid US Pacific Northwest. The region is well‐suited for small grain production, and there is a strong market for organic food products on the US West Coast. However, many growers encounter significant and persistent challenges with weed management, particularly management of perennial weeds such as Canada thistle [Cirsium arvense (L.) Scop.] and field bindweed (Convolvulus arvensis L.), but also common winter and spring annual grass weeds including cheatgrass (Bromus tectorum L.) and wild oat (Avena fatua L.). Coupled with the need to minimize soil disturbance, weed management can become nearly intractable and production limiting. From 2004 to 2024, several short and intermediate studies have been conducted to assess weed control tactics and crop rotation effects on weed management. Lessons learned include incorporating alfalfa (Medicago sativa L.) and spring barley (Hordeum vulgare L.) into rotations for suppression of field bindweed, or alfalfa and winter triticale (x Triticosecale Wittmack) for suppression of Canada thistle. Optimization of cultural inputs, particularly seeding rate, are critical for each crop in rotation. Animal integration and new crops such as quinoa (Chenopodium quinoa Willd.) are alternatives to conventional crops and potentially profitable. Incorporation of precision mechanical and chemical systems is feasible in narrow‐row cereals, and when combined with crop rotation, it could reduce or eliminate the need for repeated transitions back to convention production for organic growers.

Elucidating the eco-friendly herbicidal potential of microbial metabolites from Bacillus altitudinis.

Microbial herbicides play a vital role in agricultural preservation, amid growing concerns over the ecological impact from extensive development and use of chemical herbicides. Utilizing beneficial microbial metabolites to combat weeds has become a significant focus of research. This study focused on isolating herbicidal active compounds from Bacillus altitudinis D30202 through activity-guided methods. First, the n-butanol extract (n-BE) of B. altitudinis D30202 underwent fractionation using macroporous adsorption resin D101 and Sephadex LH-20, identifying Fr. F as the most potent segment against wild oats (Avena fatua L.). Ultra-performance liquid chromatography - quadrupole time-of-flight mass spectrometry (UPLC - QTOF-MS) identified nine compounds in the active fraction Fr. F. Subsequently, three subfractions (Fr.F-1 to Fr.F-3) were derived from Fr.F via semi-preparative liquid chromatography, resulting in methyl indole-3-acetate (MeIAA) purification. MeIAA, functioning as an auxin analog, exhibited effects of indole-3-acetic acid (IAA) on wild oats' growth, with a root length median inhibitory concentration of 81.06µg/ml. Furthermore, we assessed MeIAA's herbicidal impact on five weed species across diverse families and genera, providing a first-time analysis of MeIAA's mechanism on wild oats. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed structural damage to leaves and roots post-MeIAA treatment. MeIAA treatment increased superoxide anion and hydrogen peroxide levels in wild oat roots, alongside with elevated peroxidase (POD) and superoxide dismutase (SOD) activity, chlorophyll-degrading enzymes (Chlase, MDACase), malondialdehyde (MDA) content, and relative conductivity in leaves. Conversely, it decreased catalase (CAT) activity and chlorophyll content. Therefore, this study provides a new material source and theoretical foundation for ecologically sustainable agricultural weed control.

Effect of Different Weed Management Practices on growth and yield in Potato at Khumaltar, Lalitpur, Nepal

Potato (Solanum tuberosum L.) is the fifth most important crops in the world in terms of production with an estimate of 375 million metric tons. In Nepal, potato ranks second in terms of production and sixth in terms of area coverage. Potato production is affected by weed infestation. Weeds compete with crops for nutrients, water and other resources, which eventually reduce the crop yield. The critical period of crop-weed competition for potato is 25-40 days from planting depending on the climatic-zone and planting seasons. The most common method of weed control in Nepal is manual method, while herbicides are uses in less areas. Weeds are considered as the major problem in conventional and organic farming, due to lower yields by weeds and higher costs of labor for weed control. Mulching is one of the best and safest practice for effective weed management in potato due to which micro-climate manipulation is developed. Metribuzin is widely used herbicides in potato that controls a range of broadleaf weed species and suppresses many grassy weeds. To study the performance of different weed management practices in potato ten treatments were set up viz., three herbicides (pendimethalin@ 1.0 kg a.i ha-1, metribuzin@ 0.5 kg a.i ha-1 and atrazine @ 0.25 kg a.i ha-1) constituting seven treatments, one mulching with rice straw, one treatment with two manual hoeing, and another treatment with no any weed management practices as control.The treatments were laid out in RCB design with 4 replications. The potato variety Janak Dev was planted on 12th Feb 2021 and 23rd Jan 2022 with tuber rate of 4.1 t.ha-1 with row spacing of 60 cm and plant to plant 20 cm in a plot size of 4 x 3 meter in flat bed. Growth parameters such as plant height, plant fresh and dry biomass were recorded. Data on weed density, weed dry biomass, and tuber yield were taken.The economics of the different treatments were calculated. Among the treatments metribuzin@ 0.25 kg a.i ha-1 as pre-emergence proved effective in controlling weeds showing highest weed control efficiency (200.7 %) and tuber yield (32.79 t ha-1) . However, the treatment rice straw mulch @ 6 t ha-1 produced the highest tuber yield (38.31 t ha-1), 73.4 % increased yield over control, weed control efficiency(147.1%), economic benefit (NRS 13,40,850), benefit cost ratio (4.93).The treatment rice straw mulch @ 6 t ha-1 showed superiority among the different weeds management practices.

Prioritizing weeds for biological control development in the western USA: Results from the adaptation of the biological control target selection system

Nonnative invasive plants (weeds) negatively impact native ecosystems, and their effects are likely to increase with continuing global trade. Biological weed control has been employed as a cost-effective and sustainable management option for weeds in the USA since 1902. Biological control programs require careful prioritization of target weeds to ensure the most appropriate targets are selected to obtain the greatest beneficial outcomes with available resources. The Biological Control Target Selection (BCTS) system was developed by researchers in South Africa as an objective, transparent approach to prioritizing new weed biological control targets. The BCTS system was recently modified and applied to 295 state-regulated weeds in the western USA for which no biological control agents have yet been released. This paper presents the results of that application, identifying the most suitable candidates for new biological control programs as well as problematic weeds for which the likelihood of successful biological control is low.Top-ranked species in the western USA are biennial or perennial weeds that occur in stable habitats, are established in more than one state, have traits deemed difficult to control with conventional methods, have large negative impacts and no conflicts of interest outside of the horticultural industry, and have substantial information available on potential biocontrol agents. Fifteen of the 20 top-ranked species are already targets of ongoing biological control programs in the USA. When species with current programs are excluded from the analysis, the next 20 top-ranked species largely differ by having less information available on potential biological control agents and having native or economically important congeners in the USA. Results from this framework provide valuable insights to the prioritization of current and future biocontrol research programs in the western USA.

Growth, Yield and Grain Quality of Cowpea (Vigna unguiculata (L.) Walp.) and Weed Flora as Affected by Physical and Chemical Methods of Weed Control

Growth, Yield and Grain Quality of Cowpea (<scp><i>Vigna unguiculata</i></scp> (L.) Walp.) and Weed Flora as Affected by Physical and Chemical Methods of Weed Control

Development of Brassica carinata A. Braun resistant to acetolactate synthase–inhibiting herbicides

AbstractBrassica carinata A. Braun (carinata) has become an important oil crop for biofuel production in subtropical regions. Carinata is highly sensitive to acetolactate synthase (ALS)‐inhibiting herbicides, limiting its introduction into existing crop rotations. The objective of the study was to develop carinata lines resistant to ALS‐inhibiting herbicides. A susceptible carinata line was crossed with a resistant Brassica napus L. line. Lines derived from those crosses were screened at high doses of imidazolinones, which allowed identifying five lines with high levels of resistance. Doses to reduce plant growth 50% (GR50) and cause 50% injury (ID50) were four to nine times greater than susceptible lines. Resistant lines exhibited cross resistance with halosulfuron (sulfonylurea). Resistance was confirmed under field conditions with doses 2X and 4X for imazethapyr and 4X–8X for halosulfuron of their respective label doses. While susceptible lines died, resistant lines exhibited no injury or growth reductions compared with nontreated controls. Sequencing of the ALS gene indicated that all resistant lines carried a Trp574Leu amino acid substitution, a mutation responsible for resistance in other species. Crosses between resistant lines and a susceptible line demonstrated that the inheritance of the mutation corresponded with the resistance phenotype in the F2. The resistance trait behaved as a single, fully dominant allele, which makes it easier to transfer it to carinata lines with desirable agronomic traits. The resistant lines developed here provide flexibility for use in multiple crop rotations and opens the possibility to use ALS‐inhibiting herbicides for weed control within this crop's growing season.

The Impact of Polydimethylsiloxane as a Herbicide Adjuvant for Weed Control in the Lime Citrus × aurantifolia (Christm.) Swingle Plot

The objective of this research was to evaluate the effect of polydimethylsiloxane (PDMS) CH3[Si(CH3)2O]nSi(CH3)3 as an adjuvant in bioherbicides and synthetic herbicides (chemicals) for weed (Johnson grass S. halepense and star grass Cynodon sp.) management in the lime plot. A total of 20 treatments were conducted, which included bioherbicides and synthetic herbicides, each with three replications, the dose was 50% more polydimethylsiloxane and 100% according to the product label. The experimental design was a randomized block design, with a factorial arrangement with three factors: A (products) with 10 levels, B (adjuvants) with 2 levels and C (evaluation dates) with 5 levels, each block consisted of an area of 5 m by 4 m. The assessment was carried out periodically, every week (5 evaluations), the scale proposed by EWRS was used. The results were in percentages and a 3-factor factor analysis was performed, where A (products) = 10 levels, B (adjuvants) = 2 levels and C (evaluation dates) = 5 levels, and the mean comparison test with Tukey (&amp;alpha; &amp;le; 0.05), using SAS software. According to the results obtained, a significant difference is only presented between factors A (products) and B (adjuvants) (P &amp;lt; .0001). In factor A, the highest levels in weed control were glyphosate, diuron + carfentrazone and ammonium glufosinate with an average of 80.8, 74.0 and 70.8%, respectively. Regarding the interaction between the factors, only the A*B factors were present (P &amp;lt; .0001), only in the glyphosate, BH2 and diuron were the treatments with the highest interaction when using the 50% dose + polydimethylsiloxane as an adjuvant at a dose of 2 ml per 1 L of water with 76.2, 72.93 and 71.33%, respectively. The date when the treatments had the highest weed control effect was at the second and third week. These results underline the effect of polydimethylsiloxane to optimize the use of herbicides, not only in combination with chemical herbicides, but also with bioherbicides, offering an efficient and economic alternative for weed management (Johnson grass S. halepense and star grass Cynodon sp.).

Effect of Crimson® NG Adjuvant on Glyphosate Efficacy in Corn

There is limited published data on the impact of the addition of Crimson&amp;reg; NG to glyphosate on weed control efficacy in corn under Ontario environmental conditions. Four field experiments were conducted at the University of Guelph, Ridgetown Campus, Ridgetown, Ontario during 2022 and 2023 with two water sources to evaluate weed control with glyphosate alone and in combination with Crimson&amp;reg; NG. Glyphosate was applied at rates of 900, 1029, or 1221 g ae ha-1, with and without Crimson&amp;reg; NG at 1.0 and 2.5% v/v, using water with 56 ppm (Ridgetown) and 1600 ppm (Plattsville) hardness. Results showed that glyphosate at 900 g ae ha-1 controlled velvetleaf, Powell amaranth, common ragweed, common lambsquarters, barnyardgrass, and giant foxtail 97-100%, independent of water hardness. Neither increased glyphosate rates nor the addition of Crimson&amp;reg; NG significantly improved weed control. No corn injury was observed with all herbicide/adjuvant treatments evaluated. These findings confirm that glyphosate at 900 g ae ha-1 is highly effective for the control of common annual grass and broadleaf weeds. Weed control efficacy with glyphosate was not influenced by water source and there was no improvement in weed control efficacy from increasing the rate of glyphosate or from the addition of Crimson&amp;reg; NG.

The Impact of Autumn Tillage Activities on the Development of Weeds in Grape Crops

The article examines the impact of autumn tillage activities on the development of weeds as an element of agrotechnical control technology with integrated weed protection. In order to optimize the measures of autumn tillage in weed control, the main plowing and loosening of the soil around grape bushes in Ganja-Dashkasan district at different depths and at different times were studied. As a result of the research, it was found that if deeper plowing of the soil (25-28 cm) and deeper loosening of the soil around grape bushes (25 cm), depending on soil and climatic conditions, is carried out in October, it has the effect of reducing the number of weeds compared with other options, while the biological efficiency in this option becomes higher.

Sustainable integrated weed control strategies to reduce herbicide use in sunflower production

This research aims to develop integrated weed control strategies that can effectively reduce the quantity of herbicides used in cultivation of sunflower. To address the challenge of weed management in mechanized crop fields and mitigate the adverse effects on the ecosystem, an experiment with 10 treatments was arranged in randomized block designs and replicated 3 times. The treatments included combinations of herbicide application, band application of herbicide and power weeder weeding. The higher weed control efficiency (WCE) was achieved in a weed-free environment. Additionally, higher WCE was observed in the treatment where weeds were managed through band application of pendimethalin (38.7 capsule suspension (CS)) in the seed row as a pre-emergence method and weeding was done with a power weeder twice. These 2 treatments registered more than 90 % WCE due to lesser weed occurrence. The present investigation also registered higher grain yield under weed-free control (2212 kg/ha). It was tailed by Pre-emergence (PE) herbicide (1 kg/ha of Pendimethalin (38.7 CS)) in seed row after irrigation followed by (fb) power weeder twice (on 15-20 and 30-35 DAS), PE herbicide (1 kg/ha of Pendimethalin (38.7 CS)) in seed row before irrigation fb power weeder twice (on 15-20 and 30-35 DAS) and PE herbicide (1 kg/ha of Pendimethalin (30 EC)) in seed row after irrigation fb power weeder twice (on 15-20 and 30-35 days after sowing (DAS)). Based on the results, pendimethalin (38.7 CS) can also be applied either before or after irrigation, as it will not significantly lose its efficacy in controlling weeds. These findings have practical implications for sunflower cultivation, offering effective strategies for integrated weed control.

Selectivity of pre-emergent herbicides in cassava (Manihot esculenta Crantz) and its relationship with the stem cutting planting system

Cassava (Manihot esculenta Crantz, Euphorbiaceae), an important source of food for millions of people in the world, is distributed mainly in Asia, Africa, Latin America, and the Caribbean. Weeds are important biotic constraints on cassava production, and herbicide application can provide effective weed control in this crop. However, the different possibilities of herbicide selectivity (factors associated and not associated with the plants) must be studied before implementation. The aim of this study was to evaluate the effects of the combination of different pre-emergence herbicides and two stem cutting planting systems (vertical and horizontal) on phytotoxicity and several agronomic traits of the cassava crop. The experiment was conducted through a factorial arrangement in a completely random design in Corrientes, Argentina. The factors studied were planting systems (horizontal and vertical position), weed control methods (hoeing or application of diuron, S-metolachlor, pendimethalin or clomazone, 625; 1920; 900 and 1000 g a.i. ha−1, respectively), and cropping seasons (2018–2019 and 2019–2020). The following variables were measured: phytotoxicity, plant height, relative plant stand, total weight of tuberous roots per plant, starch concentration of tuberous roots, and starch production per ha. The highest precipitations occurred in the 2018–2019 cropping season. The vertical planting system in combination with herbicides showed lower phytotoxicity values and higher values of plant height, starch concentration, and starch production per ha than the horizontal planting system. The highest phytotoxicity values were recorded with the application of diuron combined with the horizontal planting system and in the 2018–2019 season, with a 33.33% decrease in relative plant stand compared to the use of hoeing. Starch concentration remained unchanged with the use of clomazone and pendimethalin, whereas the effect of these herbicides on starch production varied with the cropping season, decreasing only in 2019–2020. Starch production was significantly lower with the use of S-metolachlor (up to 55.29% in 2018–2019) and of diuron (up to 60.57% in 2019–2020) than with the use of hoeing. In conclusion, phytotoxicity values were higher for the horizontal planting system than for the vertical system. The herbicide with the highest phytotoxic effect on the cassava crop was diuron; the effect increased when combined with the horizontal planting system in the cropping season with higher rainfall. This work provides the basis for integrated weed management concerning the use of herbicides and their selectivity according to planting systems for cassava crops.

Advancements in smart agriculture through innovative weed management using wavelet-based convolution neural network

Smart agriculture has shifted the paradigm by integrating advanced technologies, particularly weed management. This paper introduces an innovative approach to weed control by applying a Wavelet-based Convolution Neural Network (WCNN). In the era of precision agriculture, our study explores the integration of WCNN into real-world scenarios, emphasizing its adaptability to diverse environmental conditions. Utilizing the spatial-frequency analysis features of wavelets and convolutional neural networks, the WCNN model is the most effective at finding weeds, classifying them, and managing them specifically in agricultural fields in real-time. This research contributes to the scientific discourse on smart agriculture and addresses the challenges of invasive weeds, presenting a sustainable solution for optimizing resource utilization. Our investigation includes a detailed exploration of WCNN’s adaptive learning mechanisms and dynamic adjustment to changing agricultural landscapes. The model seamlessly integrates with existing smart farming infrastructure, showcasing a substantial reduction in manual intervention and a simultaneous increase in agricultural productivity. We incorporate fog computing and resource optimization into our framework, enhancing the efficiency of onboard data processing. To evaluate the real-world efficacy of WCNN, we conducted comprehensive experiments in texture classification and image labelling using two distinct datasets: the plant seedling and soybean weed datasets. Results demonstrate the superior performance of WCNN, achieving higher accuracy in training and test scenarios with significantly fewer parameters than traditional CNNs. For the soybean weed dataset, WCNN achieved remarkable accuracy in the training (0.9970) and testing (0.9987) phases, with correspondingly low losses of 0.0109 and 0.0048. The WCNN model demonstrated high accuracy during training (0.9739) and testing (0.9902), with minimal losses of 0.0898 and 0.0239 in the plant seedling dataset.

Raw feedstock vs. biochar from olive stone: Impact on the sorption–desorption of diclosulam and tropical soil improvement

The addition of carbon-rich materials, such as raw feedstocks (RAW) and biochars, to agricultural soils is on the rise. This activity has many advantages, such as improving fertility, increasing water retention, and sequestering carbon. However, they can also increase the sorption of residual herbicides in the soil, reducing the effectiveness of weed control. Thus, the objective of this study was to evaluate soil improvement and the sorption–desorption process of diclosulam in soil unamended and amended with RAW from olive stone and their biochars produced in two pyrolysis temperatures (300 and 500 °C). Oxisol was used in this study, unamended and amended with RAW and biochars (BC300 and BC500) in a rate of 10% (w w−1). The sorption–desorption process was assessed by batch-equilibrium experiments and the analysis was performed using high-performance liquid chromatography (HPLC). The addition of the three materials to the soil increased the contents of pH, organic carbon, P, K, Ca, Mg, Zn, Fe, Mn, Cu, B, cation exchange capacity, base saturation and decreased H + Al. The unamended soil had Kf (Freundlich sorption coefficient) values of diclosulam sorption and desorption of 1.56 and 12.93 mg(1 − 1/n) L1/n Kg−1, respectively. Unamended soil sorbed 30.60% and desorbed 13.40% of herbicide. Soil amended with RAW, BC300, and BC500 sorbed 31.92, 49.88, and 30.93% of diclosulam and desorbed 13.33, 11.67, and 11.16%, respectively. The addition of RAW and biochars from olive stone has the potential to change the soil fertility, but does not interfere with the bioavailability of diclosulam in weed control under field conditions, since the materials slightly influenced or did not alter the sorption–desorption of diclosulam.

Ginger Phytotoxicity: Potential Efficacy of Extracts, Metabolites and Derivatives for Weed Control

The negative implications for weeds encourage the finding of novel sources of phytotoxic agents for sustainable management. While traditional herbicides are effective, especially at large scales, the environmental impact and proliferation of resistant biotypes present major challenges that natural sources could mitigate. In this study, the potential of ginger metabolites as phytotoxic agents has been investigated for the first time. Root extracts, prepared via various extraction techniques, showed phytotoxicity in wheat (Triticum aestivum L. cv. Burgos) coleoptile bioassays at 800–100 ppm, and the most active extract (prepared by sonication with ethyl acetate) was purified by chromatographic methods, yielding seven compounds: five phenolic metabolites with gingerol and shogaol structures, β-sitosterol, and linoleic acid. Some of the major phenolic metabolites, especially [6]-shogaol and [6]-gingerol, exerted phytotoxicity on wheat coleoptiles, Plantago lanceolata and Portulaca oleracea (broadleaf dicotyledon weeds). This promoted the study of a collection of derivatives, revealing that the 5-methoxy, oxime, and acetylated derivatives of [6]-shogaol and [6]-gingerol had interesting phytotoxicities, providing clues for improving the stability of the isolated structures. Ginger roots have been demonstrated to be a promising source of bioactive metabolites for weed control, offering novel materials with potential for the development of agrochemicals based on natural products.

Productivity of Wheat Landraces in Rainfed and Irrigated Conditions under Conventional and Organic Input in a Semiarid Mediterranean Environment

Wheat landraces are locally adapted populations that are suitable for low-input agronomic management and constraining pedo-climatic conditions. The productivity of landraces under high-input and optimal conditions is usually lower than modern wheat varieties. The present study compared the response of Sicilian wheat landraces and modern varieties to organic management, including organic fertilization, and conventional management, including mineral fertilization and chemical weed control, under rainfed condition and supplementary irrigation in a field trial conducted on a xerofluvent soil in a semiarid Mediterranean climate. Modern varieties were on average more productive than landraces, although certain landraces achieved comparable yields, in particular under organic management. The increase in grain yield under conventional management in comparison with the organic management was higher for modern varieties than landraces. The loss of productivity in rainfed conditions was lower for landraces compared to modern varieties. The grain quality traits were similar between landraces and modern varieties and in both cases the conventional management led to an improvement of the traits. These findings highlight the resilience and adaptability of traditional wheat landraces to low-input agricultural systems and offer valuable insights into improving the sustainability and productivity of wheat production in Mediterranean environments.

Recognition of maize seedling under weed disturbance using improved YOLOv5 algorithm

Using UAV-based RGB images to recognize maize seedlings is of great significant for precise weed control, efficient water and fertilizer management. However, the presence of weeds with morphological resemblances at the maize seedling stage affects the recognition of maize seedlings. This research employs UAV RGB images and deep learning algorithms to achieve accurate recognition of maize seedlings under weed disturbance. Firstly, the adaptive anchor frame algorithm is employed to intelligently select optimal anchor frame sizes suited for the maize seedling from UAV images. This strategic selection minimizes time and computational demands associated with multiple anchor frame sampling. Subsequently, the Global Attention Mechanism (GAM) is introduced, bolstering feature extraction capabilities. A range of deep learning models, including YOLOv3 and YOLOv5, are applied for maize seedling recognition, culminating in the identification of an optimal model. To account for real-world scenarios, we investigate the influences of UAV flight height and weed disturbance on maize seedling recognition. The results indicate a multi-class Average Precision (mAP) of 94.5 % and 88.2 % for detecting maize seedlings at flight heights of 15 m and 30 m, respectively, with an average detection speed of 0.025 s per single image. This emphasizes the efficacy of the improved YOLOv5 deep learning model in recognizing maize seedlings under weed disturbance using UAV RGB images.