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The intrusion of weeds into fertile areas has resulted in significant global economic and environmental impacts on agricultural production systems and native ecosystems, hence without ongoing and repeated management actions, the maintenance or restoration of these systems will become increasingly challenging. The establishment of herbicide resistan...
Contexts in source publication
Context 1
... development of fungi-based bioherbicides has shown increasing success for the control of various weeds (Table 2) [6,9,[42][43][44][45][46], and achievements in this field have dated back to the 1950s when Russian scientists mass-produced and formulated the spores of Alternaria cuscutacidae to control holoparasite Cuscuta species (dodder) [18]. Since then, multiple mycoherbicides have been established and made commercially available in Australia, Canada, China, South Africa, the Netherlands and the USA [6,9,[42][43][44][45][46][47][48][49]. ...Context 2
... then, multiple mycoherbicides have been established and made commercially available in Australia, Canada, China, South Africa, the Netherlands and the USA [6,9,[42][43][44][45][46][47][48][49]. Among these products, BioChon™ [43], Chontrol™/Ecoclear™ [6,50], Myco-Tech™ [6,50] and Stumpout ® [47,49] have been developed for the control of woody weeds (Table 2). These mycoherbicides, which are often applied via a mycelium paste to the target weed's cut stump, eventually block the vascular system of the plant with vigorously growing mycelia, whilst preventing it re-sprouting and increasing its decomposition [6,7,43,50]. ...Context 3
... literature suggests that fungi from the genus Colletotrichum are one of the mostused species within mycoherbicide formulations [48,54,[56][57][58][71][72][73]. Previous research developments using this genus have resulted in the production of several mycoherbicides (Table 2) including BioMal ® (sourced from C. gloeosporioides f. sp. malvae) [56,57,74], Col-lego™/LockDown™ (sourced from C. gloeosporioides f. sp. ...Context 4
... drawbacks have resulted in a lower demand for these products because their actions limit their use [75,76]. These limitations have also been noted in several other developed mycoherbicides such as Casst™ (sourced from Alternaria cassiae) [42], DeVine ® (sourced from Phytophthora palmivora) [65], Dr. Biosedge ® (sourced from Puccinia canaliculata) [67], Sarritor™ (sourced from Sclerotinia minor) [51,68], Smolder ® (sourced from Alternaria destruens) [51,52] and Woad Warrior ® (sourced from Puccinia thalaspeos) [7] (Table 2). In this regard, future research should aim to develop mycoherbicides that can be sustainably and economically applied for the long-term control of weeds. ...Context 5
... this regard, recent developments in this field have identified several other sources of fungi that have the potential to be formulated as a mycoherbicide, but these have yet to be commercialised for application ( Table 2). Several of these fungi include Albifimbria verrucaria, (formally Myrothecium verrucaria) [25,53], Fusarium oxysporum f. sp. ...Citations
... The use of soil microorganisms as bioherbicides relies on their ability to detoxify allelochemicals secreted in the soil by weeds. Moreover, these microorganisms can be host-specific, promoting crop plant growth while inhibiting weed growth (Bo et al. 2020;Ramesh and Abinaya 2022;Roberts et al. 2022;Jelena et al. 2023;Charudattan 2024;Tan et al. 2024). ...
Aim
This study aims to evaluate the impact of seed primimg with soil microorganism on the germination and metabolism of pearl millet seeds when exposed to the allelopathic effects of some specific weed extracts.
Methods
Pearl millet seeds were categorized into five distinct groups. Four of these groups were subjected to priming with different soil microorganisms: Bacillus velezensis, Pseudomonas fluorescens, Serratia marcescens, and Trichoderma viride. The remaining, fifth group underwent hydropriming. Subsequently, these groups were subjected to germination in the presence of weed extracts, a process that extended over five days. Following germination, various factors were assessed, including germination percentage, radicle and plumule length, and seed vigor. Furthermore, the study encompassed the analysis of biochemical parameters such carbohydrate and phytate hydrolysis, oxidative stress markers, antioxidant enzyme activity, and secondary metabolite.
Results
The findings of the study revealed that biopriming of pearl millet seeds with soil microorganisms led to a significant enhancement in germination, even when exposed to different weed extract treatments. This improvement was chiefly manifested through heightened levels of antioxidant enzymes, which mitigate the oxidative stress induced by the weed treatments. Moreover, the biopriming process improved the hydrolysis in germinated seeds, resulting in energy savings and a reduction in carbon utilization for secondary metabolism through the shikimic acid pathway and the phenylpropanol pathway. This facilitated the production of defense molecules like phenols and flavonoids.
Conclusion
Seed priming with soil microorganism ultimately bolsters the seeds’ tolerance against allelochemicals originating from weed residue treatments.
... Though UV-C was tested as an alternative weed control method, the majority of terrestrial weed control methods currently used worldwide are manual/hand removal [62], mechanical removal [63,64], chemical control/herbicides [65], biological control [66,67], and fire [68]. Each control method possesses both pros and cons. ...
... Additionally, UV-C has been extensively utilized to control algae growth, although studies on its impact on plant health have so far focused on terrestrial weeds. This review particularly aims to open a new direction toward integrating the use of UV-C treatment with other eco-friendly management actions such as bioherbicides [67] as a long-term solution over traditional synthetic herbicide applications. These integrated, nonchemical eco-friendly weed control practices will undoubtedly help reduce chemical pollution and the development of herbicide resistance in environmental weeds. ...
Aquatic weeds, including invasive species, are a worldwide problem. The presence of aquatic weeds poses several critical issues, such as hindering the continuous flow of water in irrigation channels and preventing the proper distribution of adequate water quantities. Therefore, effective control measures are vital for agriculture and numerous downstream industries. Numerous methods for controlling aquatic weeds have emerged over time, with herbicide application being a widely used established method of weed management, although it imposes significant environmental risks. Therefore, it is important to explore nonchemical alternative methods to control existing and emerging aquatic weeds, potentially posing fewer environmental hazards compared with conventional chemical methods. In this review, we focus on nonchemical methods, encompassing mechanical, physical, biological, and other alternative approaches. We primarily evaluated the different nonchemical control methods discussed in this review based on two main criteria: (1) efficiency in alleviating aquatic weed problems in location-specified scenarios and (2) impacts on the environment, as well as potential health and safety risks. We compared the nonchemical treatments with the UV-C-radiation-mediated aquatic weed control method, which is considered a potential novel technique. Since there is limited published literature available on the application of UV-C radiation used exclusively for aquatic weed control, our review is based on previous reports of UV-C radiation used to successfully control terrestrial weeds and algal populations. In order to compare the mechanisms involved with nonchemical weed control methods, we reviewed respective pathways leading to plant cell death, plant growth inhibition, and diminishing reemergence to justify the potential use of UV-C treatment in aquatic habitats as a viable novel source for aquatic weed control.
... 24 Today, biological herbicides produced by microorganisms are commercially available. 25,26 Microorganisms can produce many herbicidal metabolites, whose structural features and biological functions are diverse. These compounds may be exclusive. ...
... Another herbicide which is prepared from Phytophthora palmivora, first causes root disease and then plant death. 25 Ethylene plays an important role in balancing plant growth and development and affects seed germination, root growth, and development. ...
BACKGROUND
The widespread use of chemical herbicides and the growing issue of weed resistance pose significant challenges in agriculture. To address these problems, there is a pressing need to develop biological herbicides based on bacterial metabolites.
RESULTS
In this study, we investigated the impact of the cell‐free culture filtrate (CFCF) from the ZT isolate, a bacilliform bacterium obtained from diseased wheat seeds, on the germination and seedling growth of various plant species, including wild oat, ryegrass, redroot, wheat, and chickpea. The results revealed that CFCF had a detrimental effect on the fresh and dry weight of stems and roots in most of the studied plants, except chickpeas. The CFCF was further subjected to separation into aqueous and organic phases using chloroform, followed by the division of the aqueous phase into 13 fractions using an alumina column. Notably, both the aqueous phase (20%) and all 13 fractions (ranging from 50% to 83%) displayed the ability to reduce the root length of ryegrass, a monocotyledonous weed. Liquid chromatography–mass spectrometry (LC–MS) analysis identified that fractions 3 and 7, which were effective against ryegrass but not redroot, contained Cry family proteins, including Cry10 Aa, Cry4 Ba, and Cry4 Aa. Additionally, 16s rRNA gene sequencing revealed that the ZT isolate is closely related (98.27%) to Bacillus wiedmannii.
CONCLUSION
Conclusively, metabolites from the ZT bacterium hold promise for monocotyledonous weed‐targeted herbicides, providing a constructive strategy to confront agricultural issues tied to chemical herbicides and weed resistance. © 2024 Society of Chemical Industry.
... aeschynomene) [113,120], Lubao1 and Lubao 2 (from C. gloeosporioides) [114], Velgo ® (from C. coccodes) [119], and C. truncatum (not yet commercially developed) [122]. Although fungi are effective in eliminating weeds, they are not widely used because they are usually more expensive than chemical herbicides, and their success in weed control is not as suitable as that of chemical herbicides [127,128]. These limitations are shared by several other developed fungal bioherbicides such as Casst™ (from Alternaria cassiae) [111], DeVine ® (from Phytophthora palmivora) [129], Dr. Biosedge ® (from Puccinia canaliculata) [130], Sarritor™ (from Sclerotinia minor) [131,132], Smolder ® (from Alternaria destruens) [127,132], and Woad Warrior ® (from Puccinia thalaspeos) [133]. ...
... Although fungi are effective in eliminating weeds, they are not widely used because they are usually more expensive than chemical herbicides, and their success in weed control is not as suitable as that of chemical herbicides [127,128]. These limitations are shared by several other developed fungal bioherbicides such as Casst™ (from Alternaria cassiae) [111], DeVine ® (from Phytophthora palmivora) [129], Dr. Biosedge ® (from Puccinia canaliculata) [130], Sarritor™ (from Sclerotinia minor) [131,132], Smolder ® (from Alternaria destruens) [127,132], and Woad Warrior ® (from Puccinia thalaspeos) [133]. Therefore, future research should be directed toward reducing the production cost of fungal bioherbicides while searching for fungi with better herbicidal efficacy. ...
Weeds compete with crops for water and nutrients and can adversely affect crop growth and yield, so it is important to research effective weed control methods. This paper provides an overview of the impact of weeds on crop yield and describes the current state of research on weed management in field herbaceous crops. Physical weed control mainly refers to thermal technologies represented by flame weed control and laser weed control, which can efficiently and accurately remove weeds. Mechanical weed control requires a combination of sensor technologies, machine vision technology, and high-precision navigation to improve weed control accuracy. Biological weed control relies heavily on plant extracts and pathogens to create herbicides, but it is costly, and some can be toxic to mammals. Chemical weed control is a common method, resulting in environmental pollution and weed resistance. To reduce the use of chemical herbicides, scholars have proposed integrated weed management strategies, which combine biological control, control of the seed bank, and improve crop competitiveness. Integrated weed management strategies are considered to be the future direction of weed management. In conclusion, physical, mechanical, biological, and chemical weed control methods are commonly used in weed management. Each method has its applicable scenarios, and the implementation of integrated weed management strategies can lead to better weed control, improving crop yield and quality. The main objective of this review is to organize the research progress on weed management methods for herbaceous crops in the field and to provide a reference for the agricultural sector to develop weed control strategies. Specifically, this paper categorizes weed management methods into four groups, discusses and presents the advantages and disadvantages of the aforementioned weed control methods, and discusses future research directions.
... Currently, botanical and phytotoxins, such as essential oils, appear to be the most efficient agents for the biocontrol of weeds (Acheuk et al. 2022). Roberts et al. (2022) discuss the topic in depth, including commercial products available on the market today. Marrone (2023) takes a more marketoriented approach to the topic and provides future prospects for weed control. ...
... Furthermore, intensive application arises questions about the risk of their transfer to main crops. Today there is no widely used commercial biological herbicide and most BCAs for weed management are sold in countries outside the EU(Bremmer Johan et al. 2021;Roberts et al. 2022). By 2010, unintentional introductions of BCAs for weed control in the EU accounted for all available weed-related BCAs(Shaw et al. 2018). ...
Global agriculture is heavily dependent on sustainable plant protection. Worldwide, the concept of integrated pest management (IPM) is being followed. IPM utilizes a range of strategies, with chemical synthetic pesticides being employed only as a last resort. However, in agricultural practice, farmers continue to rely primarily on this option. To further reduce this dependence, new strategies are being sought to strengthen the use of biological control within the IPM approach including the identification of novel non-synthetic natural compounds. Here, we discuss and report on the state of the art in biological control research in areas such as biocontrol agents and application of ecological principles. These practices can help to establish sustainable plant protection systems, with the greatest impact achieved when they are used in appropriate combinations. We highlight the conditions that currently prevent or hinder the increased use of biocontrol measures. On the background of agroecological experiences, we discuss why additional advancements in plant protection practices are imperative to more effectively break the life cycles of pests, diseases and weeds. We emphasize the significance of a judicious application of chemical control technologies, adapted to local conditions. Additionally, we highlight the key role and expertise of operators in implementing these practices and their knowledge thereof.
... Out of this total loss, $76.3 billion is attributed to weeds only (Oerke, 2006). The annual losses caused by weeds related to their management and production costs has been estimated to over US$26 billion in the USA, AU$ 3.3 billion in Australia and US$11 billion in India (Chauhan, 2020;Llewellyn et al., 2016;Gharde et al., 2018;Roberts et al., 2022). In India, the weedrelated losses in agricultural production contribute to about 33%, which is higher than the losses caused by any other pest or disease (Soni et al., 2023). ...
... The agriculture sector is facing major challenges related to the increase of global population and food security that threatens globally. Since 1940s, the primary tool to manage weeds has been with synthetic herbicides/weedicides, which accounted for over 44% of all pesticides sold globally (Roberts et al., 2022). Though chemical herbicides are the most effective and expeditious tools of weed management, but their constant use has led to bioaccumulation of carcinogenic chemicals in our food and environment which are responsible for cancer, birth defects, respiratory and skin problems in humans, and in reducing beneficial soil microbiota, especially involved in nutrient cycling and soil fertility, thereby affecting the crop productivity/yields. ...
... The weed killing mechanism by a bioherbicide can be due to an array of mechanisms, such as production of several enzymes which can cause degradation of host's cell wall, lipid membranes and proteins; production of phytotoxic secondary metabolites and peptides; causing several metabolic changes in the host which can reduce the function of cellular activities, enzymes and hormones leading to decreased nutrient absorption, deregulation of photosynthesis membrane permeability, induced lipid peroxidation, and inhibition of seed germination and development. All these factors can alter a plant's photosynthetic rides, increase oxidative stress and influence stomata closer, finally reducing plant growth, increasing senescence and causing death of the inoculated weed (Roberts et al., 2022). ...
A weed, a kind of pest, is a plant growing where it is not desired, or a plant out of its place. Weeds are a major threat to biodiversity and agricultural productivity. The annual losses caused by weeds has been estimated to over US$26 billion in the USA, AU$ 3.3 billion in Australia and US$ 11 billion in India exclusively in 10 major crops. The rising awareness about the potential health risk with chemical residues among individuals and farmers, emphasis is on growing organic crops to keep us healthy and a long life. In addition, the constant use of herbicides in agriculture system also paves the way for the emergence of resistance of weed variety. Bioherbicides, an eco-friendly alternative to non-chemical management of weeds, are defined as the formulations based on indigenous living host-specific microorganisms and ancillary components applied in an inundative manner similar to chemical herbicides. The term microbial herbicide preferably be used for microbial-based formulations. These are derived from fungi, bacteria and viruses. The bioherbicides market is rapidly growing and expected to witness market growth at a rate of 15% and is expected to reach US$1.84 by 2029. In spite of all efforts, acceptance of bioherbicides by the users is low due to a wide range of constraints (e.g., environmental, technological, host-specificity, regulatory, funding and human-related). Environmental conditions playing a significant role on the microbial germination, penetration, infection and biocontrol efficacy of the target host. Twenty-six microbe-based herbicides have been developed globally. At present, 13 bioherbicides are available in the market namely DeVineTM, CollegoTM (LockdownR), BioMalR, BioChonTM, MycoTechTM, Chontrol™ (EcoClearTM), SmolderR, SarritorTM, SolvinixR, Gibbartrianth, BiophomaTM and Di-Bak ParkinsoniaR. For successful deployment of bioherbicides into agriculture, horticulture and forestry, in addition to boosting their market, scientists need to develop consumer-friendly bioherbicides with a long-shelf life, non-effected by environmental conditions, ability to control varied weeds in a crop, and with a biocontrol efficacy better than or at par with the synthetic herbicides. Objective of this review is to discuss biocontrol strategies for controlling weeds, phases of bioherbicide development, market, current global status, development of currently available bioherbicides, constraints/limitations in their production & demand and future prospects for their adoption in weed management system.
... Biological weed control remains relatively unexplored, mainly due to the challenges of implementing it on a large scale (Roberts et al., 2022). Recent studies have documented sourgrass infection by fungi, shedding light on the potential of biological control as a non-chemical alternative for managing this weed. ...
Sourgrass [ Digitaria insularis (L.) Mez ex Ekman] is one of the most challenging herbicide-resistant weeds in the grain-producing areas of Southeast, Central-west, and Northeast of Brazil. This species is a perennial grass that is highly competitive with the C4 photosynthetic pathway. It easily adapts to different environments and reproduces through both seed and rhizomes. The objective of this review was to compile what is known about sourgrass biology, the state of herbicide resistance and its associated mechanisms, and main weed management strategies. The high seed viability, ease of dispersal and the strong propensity to develop resistance to herbicides like glyphosate and acetyl coenzyme A carboxylase (ACCase) inhibitors in the prevalent no-tillage system in Brazil make the sourgrass one of the most difficult weeds to control. Due to the great genetic variability, the resistance mechanisms conferring glyphosate-resistance among sourgrass populations range from reduced absorption, altered translocation, enhanced metabolism, target-site mutations, and 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) overexpression. In addition, Trp2027Cys mutation was found to confer cross-resistance to ACCase inhibitors. Sourgrass management strategies include herbicide rotation, herbicide tank mix or sequential applications, as well as the use of mulch to reduce infestations. These measures must be implemented before crop sowing because the range of management options is greater than in after crop sowing. Additionally, the best control of sourgrass is achieved when management is carried out during the early growth stages, before the plants develop rhizomes and form clumps.
... Most companies developing biopesticides are considered minor and medium sized, while large multinational companies have invested little in biopesticide discovery. One reason is the need for significant modifications in its current screening methodology, requiring a large material investment and a technical team with experience in fermentation and microbial formulations [179,181,184]. Perhaps the path to success will be establishing multidisciplinary teams, including participants from academia, government, and industry, who, using their knowledge and experience, can provide different perspectives to achieve advancement. ...
This review aimed to show that bioherbicides are possible in organic agriculture as natural compounds from fungi and metabolites produced by them. It is discussed that new formulations must be developed to improve field stability and enable the commercialization of microbial herbicides. Due to these bottlenecks, it is crucial to advance the bioprocesses behind the formulation and fermentation of bio-based herbicides, scaling up, strategies for field application, and the potential of bioherbicides in the global market. In this sense, it proposed insights for modern agriculture based on sustainable development and circular economy, precisely the formulation, scale-up, and field application of microbial bioherbicides.
Graphical abstract
... In a long search for effective bioherbicides to control weeds in agricultural lands, there have been relatively few successes in both the biocontrol and the commercialization. 1,2 This has been despite considerable effort by weed scientists, entomologists, plant pathologists and agronomists. One of several exceptions in the quest for a commercialized bioherbicide would be the successful biocontrol of strangler weed (Morrenia odorata) in citrus by the application of the fungal plant pathogen, Phytophthora palmivora. ...
... Yet, there are fewer than two dozen registered bioherbicides in the world and most have not seen success commercially. 1,19,20 One of the attempts to use F. oxysporum as a bioherbicide was for Striga, using a wild-type strain called Foxy2 from Ghana for bioherbicide development in Kenya. 21 This product did not have adequate efficacy in the field and therefore, despite high level development for over a decade, Foxy2 was not commercialized. ...
The high‐level view of global food systems identifies three all‐encompassing barriers to the adoption of food systems solutions: knowledge, policy, and finance. These barriers, and the siloed characteristics of each of these, have hindered the development and adoption of microbial herbicides. How knowledge, policy, and finance are related to the Toothpick Project's path of commercializing a new bioherbicide, early in the scope of the industry, is discussed here. The Toothpick Project's innovation, developed over four decades and commercialized in 2021, uses strains of Fusarium oxysporum f.sp. strigae selected for overproduction and excretion of specific amino acids, killing the parasitic weed Striga hermonthica (Striga or witchweed), Africa's worst pest threat to food security. Historically, bioherbicides have not been a sufficient alternative to the dominant use of synthetic chemical herbicides. To be used safely as bioherbicides, plant pathogens need to be host specific, non‐toxic, and yet sufficiently virulent to control a specific weed. For commercialization, bioherbicides must be affordable and require a sufficient shelf life for distribution. Given the current triple storm encountered by the chemical herbicide industry (herbicide‐resistant weeds, lawsuits, and consumer pushback), there exists an opportunity to use certain plant pathogens as bioherbicides by enhancing their virulence. By discussing barriers in the scope of knowledge, policy, and finance in the development of the Toothpick Project's new microbial bioherbicide, we hope to help others to anticipate the challenges and provide change‐leaders, particularly in policy and finance, a ground level perspective of bioherbicide development. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
... The use of biotechnologies related to genetic engineering in weed control, creating crops resistant to glyphosate, led to a simplified management of agroecosystems [8]. Recently, several bioherbicides and natural herbicides have been studied as environmentally friendly tools that should be included in sustainable and integrated weed control strategies [9][10][11]. ...
The need to reduce the use of agrochemicals in order to work towards sustainable farming systems has influenced scientific research on weeds in recent years [...]
