Search Results (1,568)

The accurate mapping of weeds in agricultural fields is essential for effective weed control and enhanced crop productivity. Moving beyond the limitations of RGB imagery alone, this study presents a cross-modal feature fusion network (CMFNet) designed for precise weed mapping by integrating RGB and near-infrared (NIR) imagery. CMFNet first applies color space enhancement and adaptive histogram equalization to improve the image brightness and contrast in both RGB and NIR images. Building on a Transformer-based segmentation framework, a cross-modal multi-scale feature enhancement module is then introduced, featuring spatial and channel feature interaction to automatically capture complementary information across two modalities. The enhanced features are further fused and refined by integrating an attention mechanism, which reduces the background interference and enhances the segmentation accuracy. Extensive experiments conducted on two public datasets, the Sugar Beets 2016 and Sunflower datasets, demonstrate that CMFNet significantly outperforms CNN-based segmentation models in the task of weed and crop segmentation. The model achieved an Intersection over Union (IoU) metric of 90.86% and 90.77%, along with a Mean Accuracy (mAcc) of 93.8% and 94.35%, respectively. Ablation studies further validate that the proposed cross-modal fusion method provides substantial improvements over basic feature fusion methods, effectively localizing weed and crop regions across diverse field conditions. These findings underscore their potential as a robust solution for precise and adaptive weed mapping in complex agricultural landscapes. Full article

One of the guiding principles of the sustainable use of herbicides is their targeted action exclusively against weeds, consisting of blocking photosynthesis and synthesis of amino acids and growth regulators. Herbicides are major elements of plant production, indispensable to the functioning of modern agriculture. Nevertheless, their influence on all elements of the natural environment needs to be continuously controlled. This review article summarizes research addressing the effects of herbicides on the natural environment and the changes they trigger therein. Herbicides, applied to protect crops against weed infestation, are usually mixtures of various active substances; hence, it is generally difficult to analyze their impact on the environment and organisms. Nonetheless, an attempt was made in this review to discuss the effects of selected herbicides on individual elements of the natural environment (water, soil, and air) and organisms (humans, animals, plants, and microorganisms). In addition, the article presents examples of the biodegradation of selected herbicides and mechanisms of their degradation by bacteria and fungi. Based on this information, it can be concluded that the uncontrolled use of herbicides has led to adverse effects on non-target organisms, as documented in the scientific literature. However, further research on the environmental effects of these chemicals is needed address the missing knowledge on this subject. Full article

Herbicides are essential tools for the phytosanitary security of agricultural areas, but their excessive use can cause problems in agricultural production systems and have negative impacts on human health and the environment. The objective of this study was to present and discuss the main causes behind the increase in herbicide commercialization in Brazil between 2010 and 2020. Data from the Brazilian pesticide database, provided by the Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA), were used. In 2010 and 2020, Brazil sold 157,512 and 329,697 tons of herbicide active ingredients, respectively, representing a 128.1% increase in commercialization over 11 years. Some herbicides, such as clethodim, haloxyfop-methyl, triclopyr, glufosinate, 2,4-D, diclosulam, and flumioxazin, showed increases in sales volumes between 2010 and 2020 of 2672.8%, 896.9%, 953.5%, 290.2%, 233.8%, 561.3%, and 531.6%, respectively, percentages far exceeding the expansion of Brazil’s agricultural area. The primary reason for this sharp increase in herbicide sales was the worsening cases of weeds resistant and tolerant to glyphosate, with species such as Conyza spp., Amaranthus spp., Digitaria insularis, and Eleusine indica standing out. This situation created the necessity of the use of additional herbicides to achieve effective chemical control of these weed species. Full article

Thousands of species of parasitic weeds, such as dodder, pose significant threats to agricultural crops due to their ability to spread rapidly through seeds. When cultivated lands become infested with dodder, the quality of production declines, leading to substantial damage. The most effective way to limit the infestation of agricultural lands by parasitic weeds, particularly dodder, is to control the quality of seeds intended for sowing. To obtain seed material free of dodder seeds, special separation machines equipped with magnetic drums are used. These machines operate on the principle of magnetic fields acting on ferromagnetic particles, which helps differentiate the physical states of the seeds intended for separation. This paper presents experimental research on magnetic drum separation techniques for removing dodder seeds from alfalfa seed mixtures. The study examines variables such as magnetic drum speed, feed rate, amounts of iron powder, water, solution (water and glycerin), and the initial content of dodder seeds. The experimental results indicated that using a water–glycerin solution at optimal concentrations for moistening the seeds enhances the separation efficiency of dodder seeds from alfalfa seed mixtures, compared to using only water. Additionally, the numerical content of dodder seeds in the A and C sorts, which primarily contain the seeds of the main crop, decreases with each pass through the machine, resulting in higher quality seed material. The research found that using appropriate parameters—drum rotation speed (20 rpm), iron powder quantity (19 g/min), and seed feed rate (25.39 g/s)—achieved a “free” classification for dodder in alfalfa seeds. These findings are valuable for evaluating the performance of separation equipment with magnetic drums to obtain high-quality seed material. They are also beneficial for designers, machine-building units, and economic agents specializing in this field. Full article

This study investigates the effects of substrate composition on root architecture, plant growth, and allelopathic secondary metabolites, specifically benzoxazinoids (BXs), in the rhizospheres of rye (Secale cereale L.) and redroot pigweed (Amaranthus retroflexus L.). Given the complexities of root exudate analysis, including the influence of substrate on root morphology and exudation, the experiment compared plant growth and BX release in two substrates: glass microbeads and a mixture of clay beads and attapulgite. Rye, pigweed, and co-cultures of the two were grown under controlled conditions, with root and shoot parameters measured to assess substrate suitability. Additionally, UPLC-QTOF-MS was used to analyze BXs in rye and rye–pigweed co-cultures. The results demonstrated that the clay bead and attapulgite mixture provided better growth conditions and was effective for BX extraction, making it a suitable substrate for studying allelopathy in controlled environments. The findings highlight the critical role of substrate composition in both plant development and the study of root exudates, with implications for better understanding of crop–weed interactions and allelopathy. Full article

The contamination of agricultural soils by microplastics (MPs) has significant implications for herbicide efficacy and soil health. This study investigates the effects of MPs on critical processes such as the sorption, desorption, and degradation of herbicides, highlighting their influence on these compounds’ mobility, persistence, and bioavailability. MPs interact with herbicides through sorption mechanisms, often reducing the availability of these compounds for weed control by retaining them on their surfaces. This sorption not only limits the immediate efficacy of herbicides but also alters their desorption process, resulting in a prolonged release into the soil environment. Additionally, MPs can inhibit microbial activity involved in herbicide degradation, increasing the time degradation of the half-life of these substances and extending their persistence in the environment. These processes collectively enhance the risks of bioaccumulation and environmental contamination. Understanding these interactions is essential for developing strategies to mitigate the impacts of MPs on herbicide performance and promote sustainable agricultural practices. Full article

Setaria viridis (green foxtail) is an invasive weed species in various agricultural systems, prompting the search for effective compounds to control its germination. The species has primary and secondary dormancy depending on the time elapsed since post-harvesting, making management strategies more difficult. Several weed plants, such as Lantana camara L., can be a source of allelochemicals with herbicidal effects, being a potential candidate for the control of S. viridis. We investigated the effects of L. camara extracts on the germination and initial growth of S. viridis seeds with different degrees of dormancy and revealed a dose-dependent bioherbicide effect. Aqueous extracts of L. camara were analyzed by HPLC-DAD and applied (0.1 to 5.0 mg/mL) to 12- and 110-day post-harvest S. viridis seeds. Seeds were evaluated daily and germination percentage (GP), speed germination index (SGI), and radicle length (RL) were calculated. Phenolic acids and flavonoids were major components of the extract. Lower concentrations (0.1 and 0.5 mg/mL) stimulated and accelerated the germination of S. viridis, breaking its dormancy. Both 1.0 and 5.0 mg/mL concentrations hindered germination, especially in 12 dph seeds. The 1.0 mg/mL concentration resulted in longer roots, whereas 5.0 mg/mL inhibited root development. Lantana camara extracts potentially stimulate germination and radicle growth of S. viridis at low concentrations while inhibiting these parameters at higher doses. These results may open new possibilities for using L. camara in weed-control strategies. Full article

Background: Rice, one of the main foods in Brazil and the world, is sensitive to chilling (0–15 °C), especially in the germination and reproductive stages. Chilling causes delayed germination and affects coleoptile elongation at the S3 stage (needlepoint), causing poor plant establishment, stunted growth, and non-vigorous plants, also impacting weed management. Elucidating the mechanisms responsible for resilience under cold conditions helps the development of tolerant cultivars. Transcription factors (TFs) act in stress response signaling, making them indispensable in the tolerance mechanism. Objective: Thus, this study aimed to identify and characterize the expression profile of transcription factors in the response to chilling stress in rice at the germination stage. Methods: To determine the transcriptional profile of 2408 genes belonging to 56 TF families, RNAseq was performed on the shoot tissue of seedlings of Oro (chilling-tolerant) and Tio Taka (chilling-sensitive) genotypes grown under control conditions (25 °C) and chilling stress (13 °C) until the S3 stage. Results: Of the total genes analyzed, 22% showed significant differential expression in the analyzed cultivars. There were 117 genes that showed significant differential expression in the tolerant cultivar, 60 of which were downregulated and 57 upregulated. In the sensitive cultivar, 248 genes had a significant differential expression, of which 98 genes were downregulated and 150 genes were upregulated. A total of 170 genes encoding TFs were commonly and significantly differentially expressed in the tolerant and sensitive genotypes. Conclusions: Here, we revealed potential new targets involved in the regulation of chilling stress in rice at the S3 stage. Full article

This study explores agroecological practices designed to improve soil quality and crop yield in small-scale agriculture, focusing on soil inoculation with beneficial bacteria over conventional fertilizers. Conducted at the SZIA Agroecological Garden MATE in Gödöllő, Hungary, the research utilizes 12 plots to evaluate different conservation tillage methods, including minimum and no-tillage, with and without microbial inoculation. Commenced in 2022, this study centers on potato cultivation (Solanum tuberosum L.) and includes comprehensive chemical and physical analyses of soil and harvested potatoes, alongside continuous monitoring of growth. Statistical analysis using One-way Anova in R revealed p-values predominantly above 0.05, indicating no significant differences across most parameters, though variations in soil plasticity and pH (KCl) were noted. Results suggest that substantial treatmeent differences may require a longer observation period. Notably, plots with microbial inoculation exhibited higher harvest weights and tuber sizes compared to control plots. Additionally, trends and interactions were found between weed abundance, total harvest, and plant height. The findings indicate that the benefits of integrated agroecological practices, including conservation tillage, may take time to materialize, emphasizing the necessity for extended observation. This research lays the groundwork for future studies, underscoring the importance of patience in achieving improvements in soil health and crop quality through sustainable agricultural methods. Full article

Recently, there has been growing interest by farmers and researchers in various agroecological approaches enhancing biodiversity and conservation including the use of natural herbicides derived from fungi to provide adequate weed control. This change is driven by growing concerns about herbicide resistance, environmental impacts and regulatory requirements. This review summarizes the results of various studies and highlights the efficacy and benefits of fungal bioherbicides in weed control. Fungi-based bioherbicides utilize the natural weed suppression capability of selected fungi to reduce weed density and competitiveness without completely eradicating the plants and such an approach is at the core of agroecology. Bioherbicides contribute to conservation by providing an environmentally friendly alternative to chemical herbicides. By reducing the reliance on synthetic chemicals, fungal bioherbicides help preserve soil health, water quality and protect non-target species, including beneficial organisms such as pollinators and soil microbes. They also promote biodiversity by selectively targeting specific weed species, leaving native plants and other organisms unharmed and favoring diversified weed flora without the dominance of a few species. Despite their promising potential, bioherbicides face several challenges, including delayed action, production difficulties and the potential toxicity of certain fungal toxins to mammals. This review highlights the growing adoption of fungal bioherbicides as an eco-friendly component of Integrated Weed Management (IWM). Further research is necessary to identify optimal fungal strains for controlling persistent weeds without putting at risk the overall biodiversity and to develop improved formulations for enhanced efficacy. Full article

Mythimna separata (Walker), a significant migratory pest in many Asian countries, can cause severe damage to wheat crops. Understanding whether wild oat can serve as an alternate host is important for informing predictive models of M. separata infestation levels in wheat fields and can improve pest and weed management strategies. We first conducted both choice and no-choice experiments and found that M. separata readily laid eggs on both wheat and wild oat, with no significant oviposition preference. However, newly hatched larvae exhibited a strong preference for wheat, with 53.34% more larvae feeding on wheat compared to wild oat. Development time from egg to adult emergence was significantly shorter in M. separata fed on wheat than on wild oat, although the durations of the larval and pupal stages varied depending on the host plant. Despite these differences in development time, host plants did not significantly affect larval survival, pupal weight, fecundity, and adult longevity. The mean number of eggs laid by females that fed on wheat and wild oat were 1202.12 and 1270.54 eggs/female, and larval survival rates were 81% and 84%, respectively. Our findings suggest that wild oat can serve as a suitable host for M. separata and may act as a refuge when wheat fields are treated with insecticides. The high larval preference for wheat over wild oat indicates that M. separata on wild oat may easily disperse to wheat, complicating pest control and highlighting the need to include wild oat in pest management strategies. Full article

Successful seed germination and plant seedling growth often require association with endophytic bacteria. Barnyard grass (Echinochloa crus-galli (L.) P. Beauv.) is a main weed during rice cultivation and has frequently been found in drought-prone fields such as cornfields in recent years. To determine whether endophytic bacteria enhance the survival chances of barnyard grass in dryland conditions, endophytic bacteria were collected from barnyard grass seeds. An endophytic bacterial strain, BC-14, was selected and confirmed as Cronobacter dublinensis based on its morphology, physiology, biochemistry, and genomic information. Moreover, C. dublinensis BC-14 secreted IAA in the Luria–Bertani broth up to 28.44 mg/L after 5 days; it could colonize the roots of barnyard grass. After the inoculation with seeds or the well-mixed planting soil, the bacterium can significantly increase the root length and plant height of barnyard grass under drought conditions. When comparing with the control group on the 28th day, it can be seen that the bacterium can significantly increase the contents of chlorophyll b (up to 7.58 times) and proline (37.21%); improve the activities of superoxide dismutase, catalase, and peroxidase (36.90%, 51.51%, and 12.09%, respectively); and reduce the content of malondialdehyde around 25.92%, which are correlated to the drought tolerance. The bacterial genomic annotation revealed that it contains growth-promoting and drought-resistant functional genes. In a word, C. dublinensis BC-14 can help barnyard grass suppress drought stress, promote plant growth, and enhance biomass accumulation, which is helpful to interpret the mechanism of weed adaptability in dry environments. Full article

Anthracocystis panici-leucophaei, causal agent of smut on Digitaria insularis (sourgrass), was evaluated as a biological control agent for this weed. Two types of inocula (teliospore and sporidia) were tested to assess its infectivity. The effects of teliospore and sporidia inoculations at different phenological stages of sourgrass were compared, as well as the potential of sporidia and teliospores in post-emergence sourgrass management. Virulence tests were conducted with the isolates obtained from D. insularis and evaluation of specificity of A. panici-leucophaei. Both teliospores and sporidia of A. panici-leucophaei are infective to D. insularis in three different phenological stages. Newly emerged plants with one pair of leaves are more sensitive to A. panici-leucophaei. Infection by A. panici-leucophaei inhibits the growth of sourgrass, decreasing several physiological parameters of D. insularis plants. The fungus produces systematic infection of sourgrass plants and may induce the formation of sori in a significant proportion of the plant panicles, partly castrating those plants. Among sixteen A. panici-peucophaei isolates tested, isolate 46 was the most virulent and inhibited the growth of sourgrass plants, and thus appears to have good potential as a biological control agent to be deployed against sourgrass. A. panici-leucophaei was demonstrated to be specific to D. insularis. Full article

Field trials were conducted at the Field Experimental Station in Winna Góra. Weed control after maize sowing increased the grain yield by 15.7% compared to that after herbicide application at the BBCH 14/15 stage. Higher effectiveness of silicon application in maize cultivation can be achieved on plantations free from primary or secondary weed infestation. The application of a 50% NPK dose increased the grain yield by 8.6%, while a 100% dose improved it by 13.9% compared to that of the control object (without mineral fertilization). Furthermore, it was observed that the effectiveness of the silicon increased with higher total precipitation during the maize growing season, as evidenced by the results from 2022. In that year, the difference between the control (without silicon application) and the treatment with silicon applied at the BBCH 15/16 stage was more than 33%. The average mass losses from the green tea bags ranged from 54.9% to 71.9% in the variant of the sowing experiment carried out after spraying with the herbicide and from 69.4% to 72.4% in the variant with herbicide spraying at the BBCH14 stage. The rooibos tea’s mass losses were lower, as expected, and ranged from 18.6% to 36.4% in the first variant and from 30.8% to 38.6% in the second variant. The mass losses of the green tea and rooibos tea were the highest in the variant with herbicide spraying at the BBCH14 stage and the lowest in the variant of the sowing experiment carried out after herbicide spraying. The stabilization factor (S) ranged from 193 × 10⁻³ to 254 × 10⁻³ in sowing after herbicide spraying and from 188 × 10⁻³ to 226 × 10⁻³ in the variant with herbicide spraying at the BBCH14 stage. The k (decomposition constant) ranged from 7.8 × 10−3 to 11.5 × 10⁻³ in the first variant and from 7.2 × 10⁻³ to 13.4 × 10⁻³ in the variant with herbicide spraying at BBCH14. Full article

Phosphite (Phi), an analog of phosphate (Pi), is an anion widely used in phytosanitary management and agricultural biostimulation schemes. Given that, unlike some species of bacteria, plants do not naturally have the mechanisms to metabolize Phi once they have absorbed it, Phi must be used in perfect coordination with adequate nutritional management of Pi in the crop since an excessive level of Phi combined with a deficient supply of Pi causes a disruption in ionic balances that can result in serious toxicity or even the death of the plant. In addition to the adequate Phi/Pi balance, high doses of Phi by themselves cause alterations in the mechanisms of perception and response to phosphorus deficiency leading to toxicity in plants. Hence, in various plant species, it has been proven that Phi can be used with herbicidal effects. Genes that encode enzymes involved in the metabolization of Phi have been isolated from bacterial genomes, and they have been transferred by genetic engineering to plant genomes, allowing the development of dual fertilization and weed control systems. This review provides background on the novel uses of Phi in agriculture and breaks down its potential use as an alternative herbicide in sustainable agriculture approaches supported by green chemistry. Full article