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Weed science plays a vital role in mitigating the negative impacts of weeds in agriculture and natural ecosystems. However, the field has received criticism for its limited theoretical foundation and excessive focus on phenomenological and narrow scope. Our contention is that weed science needs to integrate more ecological theories to foster a deeper understanding of weed ecology, biology, and management. By embracing theoretical frameworks, weed science can enhance its ability to predict and explain weed dynamics, identify underlying mechanisms, and develop sustainable management strategies. This insight emphasizes the advantages of integrating theoretical approaches and offers practical recommendations to integrate ecological theory effectively into weed science research. [ABSTRACT FROM AUTHOR]

Water hyacinth is an invasive species that spreads rapidly and causes several issues in aquatic habitats; therefore, efforts are required to eradicate weeds in aquatic ecosystems. Aquatic weed control in Indonesia using herbicide is very limited, so it can be an alternative for aquatic weed control management. This research goal was to examine the effectiveness of the herbicide with active agent Florpyrauxifenbenzyl 25 g/L in controlling and inhibiting the rapid growth of (E. crassipes). This research was carried out at the Ciparanje Greenhouse and Weed Science Laboratory, Faculty of Agriculture Universitas Padjadjaran, West Java, Indonesia, from August to October 2022. The experiment utilized a randomized block design (RBD) with eight treatments and four replications. The treatments consisted of herbicides with active ingredients Florpyrauxifen-benzyl 25 g/L doses of 5, 15, 25, 35, 45, herbicide 2,4-D DMA 825 g/L (1200), Penoxsulam 25 g/L (12.5) (g a.i/ha), and Control (Without Herbicide). According to the experiments, E. crassipes was effectively inhibited and controlled by the herbicide Florpyrauxifen-benzyl 25 g/L at a dose of 5 g a.i./ha. Florpyrauxifen-benzyl 25 g/L herbicide can inhibit relative growth rate, doubling time, number of leaves and clumps of E. crassipes up to 6 WAA. [ABSTRACT FROM AUTHOR]

Agricultural weeds frequently hybridize with each other or with related crop species. Some hybrid weeds exhibit heterosis (hybrid vigor), which may be stabilized through mechanisms like genome duplication or vegetative reproduction. Even when heterosis is not stabilized, hybridization events diversify weed gene pools and often enable adaptive introgression. Consequently, hybridization may promote weed evolution and exacerbate weed–crop competition. However, hybridization does not always increase weediness. Even when viable and fertile, hybrid weeds sometimes prove unsuccessful in crop fields. This review provides an overview of weed hybridization and its management implications. We describe intrinsic and extrinsic factors that influence hybrid fitness in agroecosystems. We also survey the rapidly growing literature on crop–weed hybridization and the link between hybridization and invasiveness. These topics are increasingly relevant in this era of genetic tools for crop improvement, intensive and simplified cropping systems, and globalized trade. The review concludes with suggested research priorities, including hybridization in the context of climate change, plant–insect interactions, and redesigned weed management programs. From a weed management perspective, hybridization is one of many reasons that researchers and land managers must diversify their weed control toolkits. [ABSTRACT FROM AUTHOR]

This document is an editorial from the journal Agronomy titled "The Future of Weed Science: Novel Approaches to Weed Management." The editorial discusses the need for new and innovative approaches to weed management in light of the European Union's focus on reducing chemical control. The document highlights various research papers that cover topics such as agroecological weed management, precision agriculture, remote sensing, and the potential role of allelopathy and nature-based compounds. The authors emphasize the importance of combining these methods, evaluating them under different conditions, and optimizing strategies for both agronomic performance and ecosystem services. [Extracted from the article]

Copyright of Turkish Journal of Weed Science is the property of Gaziosmanpasa Universitesi Matbaasi, Department of Plant Protection, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the 50th edition of Weed Research the Editor‐in‐Chief introduced the concept of 'the post‐herbicide era'. This appears increasingly prescient as herbicides continue to face ever‐increasing legislative restrictions and evolved resistance. They are also an important enabler of intensive agriculture which is a key contributor to the planetary crises, such as climate change and biodiversity loss. Integrated weed management (IWM) is the clear direction of travel for both weed science and practice, and is increasingly being holistically integrated into overall crop management. However, most definitions of 'weeds' date from the era of intensive agriculture, so may not be suitable for the post‐herbicide era and IWM. It is argued that deciding if a plant is a weed is fundamentally a 'value judgement', so weeds are, therefore, ethical and social constructs, and not a scientific concept. The proposed definition is 'A plant, or population of plants, in a specific time and place, causing significant harm, either immediately or in the longer term, based on a holistic analysis of both their positive and negative attributes'. Thus, plants are defined as weeds on a case‐by‐case basis, that is, at a specific time and place, which counters the belief that a particular plant species are weeds. Significant harm is the value statement at the heart of the definition. As seedbanks and living plants persist from year to year and plants can become invasive, a caveat about the harm being in the future is required. The analysis of harm must also be holistic, for example, consider all ecosystem services that the plants provide. 'Other plants' or 'aliae plantae' are suggested to describe non‐crop plants that are not weeds that this definition creates. [ABSTRACT FROM AUTHOR]

Questions: Two scientific disciplines, vegetation science and weed science, study arable weed vegetation, which has seen a strong diversity decrease in Europe over the last decades. We compared two collections of plot‐based vegetation records originating from these two disciplines. The aim was to check the suitability of the collections for joint analysis and for addressing research questions from the opposing domains. We asked: are these collections complementary? If so, how can they be used for joint analysis? Location: Europe. Methods: We compared 13 311 phytosociological relevés and 13 328 records from weed science, concerning both data collection properties and the recorded species richness. To deal with bias in the data, we also analysed different subsets (i.e., crops, geographical regions, organic vs conventional fields, center vs edge plots). Results: Records from vegetation science have an average species number of 19.0 ± 10.4. Metadata on survey methodology or agronomic practices are rare in this collection. Records from weed science have an average species number of 8.5 ± 6.4. They are accompanied by extensive methodological information. Vegetation science records and the weed science records taken at field edges or from organic fields have similar species numbers. The collections cover different parts of Europe but the results are consistent in six geographical subsets and the overall data set. The difference in species numbers may be caused by differences in methodology between the disciplines, i.e., plot positioning within fields, plot sizes, or survey timing. Conclusion: This comparison of arable weed data that were originally sampled with a different purpose represents a new effort in connecting research between vegetation scientists and weed scientists. Both collections show different aspects of weed vegetation, which means the joint use of the data is valuable as it can contribute to a more complete picture of weed species diversity in European arable landscapes. [ABSTRACT FROM AUTHOR]

An experiment was conducted in summer, 2016 at the Department of Weed Science, The University of Agriculture Peshawar to investigate the effect of herbicides on the management, growth and reproduction of duckweed (Lemna minor). The experiment was laid out in Completely Randomized Design (CRD) with three replecations and various herbicidal treatments. Duckweed was collected from fresh water bodies and transferred to the experimental units (pots). Data were recordrd on fresh biomass, budding (%), duckweed mortality (%), plant growth, root length, frond diameter, growth of microscopic algae and macrophytes associated with duckweed, and water surface coverage (%). Results revealed that herbicides had a significant effect on duckweed fresh biomass, budding % and water surface coverage. Minimum fresh biomass (2.98 g pot-1), budding (24 %) and water surface coverage (14.67 %) were recorded for glyphosate as compared to weedy check (4.45 g pot-1, 58.7 % and 22.67 %, respectively). Moreover, highest plant mortality (24.33 %) after four weeks was noted in glyphosate. Glyphosate effectively controlled the duckweed, followed by MCPA as compared to bromaxonil, isoproturon and paraquat. Therefore, glyphosate and MCPA proved suitable, economical and less laborious for the management of duckweed for large scale infestation. [ABSTRACT FROM AUTHOR]

The evolution of weed resistance to herbicides is an ever-increasing problem that affects crop yield and food production. In Syngenta, we believe that this difficult and complex issue can be most efficiently addressed through a deep understanding of the evolutionary dynamics and mechanism of resistance. A profound knowledge of resistance is key to developing the next generation of resistance-breaking compounds with existing or novel herbicide sites of action. We use a multidisciplinary laboratory-based, glasshouse and field biology approach to study herbicide resistance and provide strong science-based solutions to delay the onset and manage resistance. We have developed and implemented simple early-season resistance detection methods to allow farmers make an informed decision for effective weed control. We have built mechanistic, individual-based computer models to design profitable, long-term sustainable weed management programs. Our zero tolerance approaches employ herbicides with different sites of action, applied in mixtures and sequences, to minimise the risk of resistance evolution. Weeds are targeted at the right growth stage with optimal herbicide formulation and spray technology for maximising weed control and depleting the seed bank. We are promoting the use of competitive crop varieties and other nonchemical methods for an integrated weed management strategy. We have a global web of external collaborations for studying and managing herbicide resistance. We are committed to farmers' education and training on herbicide resistance, and regularly share our methods and findings via conferences and peer-reviewed scientific publications for the benefit of the wider weed science community and field practitioners. [ABSTRACT FROM AUTHOR]

Sustainable strategies for managing weeds are critical to meeting agriculture's potential to feed the world's population while conserving the ecosystems and biodiversity on which we depend. The dominant paradigm of weed management in developed countries is currently founded on the two principal tools of herbicides and tillage to remove weeds. However, evidence of negative environmental impacts from both tools is growing, and herbicide resistance is increasingly prevalent. These challenges emerge from a lack of attention to how weeds interact with and are regulated by the agroecosystem as a whole. Novel technological tools proposed for weed control, such as new herbicides, gene editing, and seed destructors, do not address these systemic challenges and thus are unlikely to provide truly sustainable solutions. Combining multiple tools and techniques in an Integrated Weed Management strategy is a step forward, but many integrated strategies still remain overly reliant on too few tools. In contrast, advances in weed ecology are revealing a wealth of options to manage weeds at the agroecosystem level that, rather than aiming to eradicate weeds, act to regulate populations to limit their negative impacts while conserving diversity. Here, we review the current state of knowledge in weed ecology and identify how this can be translated into practical weed management. The major points are the following: (1) the diversity and type of crops, management actions and limiting resources can be manipulated to limit weed competitiveness while promoting weed diversity; (2) in contrast to technological tools, ecological approaches to weed management tend to be synergistic with other agroecosystem functions; and (3) there are many existing practices compatible with this approach that could be integrated into current systems, alongside new options to explore. Overall, this review demonstrates that integrating systems-level ecological thinking into agronomic decision-making offers the best route to achieving sustainable weed management. [ABSTRACT FROM AUTHOR]

The bioeconomic models developed in Weed Science consider the effect of a species on the crop. Bioeconomic models accounting for species interactions within the weed community might represent more realistic approximation to the economic outcome of weed control options in Mediterranean cereal crops. A bioeconomic model, based in community dynamics, competition and economic submodels, was developed and used to investigate the long-term agronomic, economic and environmental consequences of using herbicide-based strategies for the control of winter wild oats (Avena sterilis) and rigid ryegrass (Lolium rigidum) in winter wheat. The results of simulations indicated that different winner strategies can be postulated depending on selection criterion. Based on purely economic outcome, the best strategy was the application of half-dose herbicide to both species whereas if the goal is to achieve a long-term economically viable and environmental friendly decision making, then the strategy chosen would be the one based on a full-dose herbicide application for the control of L. rigidum and half-dose for control of A. sterilis. The sensitivity of the model to variation in economic and competition parameters was checked. The most sensitive model parameters were the potential yield and the wheat price. Bioeconomic models offer practical guidance regarding the possibilities and limitations of various strategic approaches for weed control. [ABSTRACT FROM AUTHOR]

Weeds have proved to be a huge cause of yield loss in the past and are still a recurring problem. Weeds harbor many pests and virus and bacterial carrying vectors. To date the most effective methods of control have been herbicides. Herbicides are very effective but come at a huge cost to the environment and lately there were many cases of ineffective herbicides that used to effectively control weeds. This can be referred to as herbicide resistance (HR). HR can be referred to as the genetically inherited ability of a plant to withstand toxins that usually when applied kill it. This problem has led to the invent and need to come up with not just environmentally friendly control measures but also highly effective alternate methods of weed control. To date many have been devised like allelopathy but is not 100% effective. Molecular diagnostics is a set of methods used to analyze biological markers in the genome and proteome-the genetic code and how cells express their genes as proteins. The main focus of this paper is a deeper look into molecular weed diagnosis (MWD), the various methods of HR in weeds and methods of control that have been devised from results collected. [ABSTRACT FROM AUTHOR]

Specialty crop herbicides are not a priority for the agrochemical industry, and many of these crops do not have access to effective herbicides. High‐value fruit and vegetable crops represent small markets and high potential liability in the case of herbicide‐induced crop damage. Meanwhile, conventional and organic specialty crop producers are experiencing labor shortages and higher manual weeding costs. Robotic weeders are promising new weed control tools for specialty crops, because they are cheaper to develop and, with fewer environmental and human health risks, are less regulated than herbicides. Now is the time for greater investment in robotic weeders as new herbicides are expensive to develop and few in number, organic crops need better weed control technology and governments are demanding reduced use of pesticides. Public funding of fundamental research on robotic weeder technology can help improve weed and crop recognition, weed control actuators, and expansion of weed science curricula to train students in this technology. Robotic weeders can expand the array of tools available to specialty crop growers. However, the development of robotic weeders will require a broader recognition that these tools are a viable path to create new weed control tools for specialty crops. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Copyright of Julius-Kühn-Archiv is the property of Julius Kuehn Institut and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• The physiological and growth response of Salvia aethiopis to five selected herbicides, at a variety of doses is presented. • Herbicide application was shown to affect crop performance in this species and the level of response was dependent upon the specific herbicide and the dose applied. • These data indicate that of the herbicides tested, bentazon should be the used for broad leafed weed control, for the commercial production of Salvia aethiopis. Salvia aethiopis is an aromatic species within the Lamiaceae family, used both as a herb and as an ornamental plant, the yield and quality of which, when cultivated on a commercial basis, is frequently affected by weed infestation. Therefore, the application of herbicide is often required for the commercial production of this species. Considering which, for the current study, a pot experiment based upon a completely randomized design, with three replications, was conducted to evaluate the physiological and growth response of S. aethiopis to five commonly used herbicides (bentazon, phenmedipham/desmedipham, metribuzin, oxyfluorfen and oxadiargyl). These herbicides were applied at three concentrations (0.75X, 1X and 1.25X where X is equal to the recommended dose of herbicide). The data obtained from this study, demonstrated that herbicide application led to an increase in crop damage, minimum fluorescence (F 0) and malondialdehyde content (MDA) and a concomitant decrease in the maximum quantum efficiency of PSΙΙ (F V /F M), maximum fluorescence (F M), SPAD value, relative water content (RWC), plant height and shoot and root dry weight as compared to the control. However, the level of response/tolerance was dependent upon the specific herbicide and the dose applied. Of the selected herbicides, S.aethiopis has shown to display the most tolerance to bentazon. As such, these data indicate that of the herbicides tested, bentazon should be the preferred herbicide used for broad leafed weed control, during the commercial production of this species. [ABSTRACT FROM AUTHOR]

Herbicides that act by inhibiting the biosynthesis of very-long-chain fatty acids ( VLCFAs) have been used to control grass weeds in major crops throughout the world for the past 60 years. VLCFA-inhibiting herbicides are generally highly selective in crops, induce similar symptoms in susceptible grasses and can be found within the herbicide groups classified by the HRAC as K3 and N. Even after many years of continuous use, only 12 grass weed species have evolved resistance to VLCFA-inhibiting herbicides. Here, the cases of resistance that have evolved in major grass weed species belonging to the Avena, Echinochloa and Lolium genera in three different agricultural systems are reviewed. In particular we explore the possible reasons why VLCFA herbicides have been slow to select resistant weeds, outline the herbicide mode of action and discuss the resistance mechanisms that are most likely to have been selected. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The article presents abstracts of article related to weed science including "Mutagenesis as a tool for development of broomrape control," by Evgenia Dor, Eugene Smirnov, and Joseph Hershenhorn, "A GIS cloud as a weeds mapping tool," Shay Mey-Tal and Dror Kiakov, and "Weed control in wine vineyards," by Shmuel Ovadia and Tuvia Yaacoboy.

Y oung SL (2012) True Integrated Weed Management. Weed Research 52, 107-111. Summary Using the simplest of definitions, integrated weed management has been described as 'putting components [of weed control] together, not taking them apart'. Yet, weed science has stopped at the 'field edge' in assembling the components into a truly integrated approach. What is keeping weed scientists from developing real integrated weed control regardless of space and time? The answer to this question lies with our colleagues in the engineering and computer science fields, who have made significant advances in developing automated machinery for real-time detection and control of weeds in cropping systems. By using the latest technologies that can quickly identify weeds and react with precisely targeted applications, conceptually, weed control tools could be integrated for use at anytime and at any point in a field. This paper provides justification for using a single platform in the field that can instantaneously assess individual weeds and determine the most appropriate control method, simultaneously. In addition, I have modified an existing concept design to show the potential for a highly responsive weed management system that can transcend spatiotemporal restrictions and within-field variability. [ABSTRACT FROM AUTHOR]

Research has documented the effects of tankmixing glyphosate with numerous insecticides on cotton growth and yield; however, no information is available concerning the addition of a residual herbicide such as an aqueous capsule suspension (ACS) formulation of pendimethalin to glyphosate plus an insecticide. Mixtures such as this are important as producers continue to search for costs savings in cotton production and the inclusion of residual herbicides in the planting regimen is needed to mitigate the development and spread of glyphosate-resistant (GR) weeds. Therefore, this research during 2006 and 2007 determined the effects of postemergence (POST) combinations of glyphosate applied alone or plus the ACS formulation of pendimethalin with eight different insecticides on second-generation GR cotton. Glyphosate (®Roundup Weathermax) was applied at 1058 g ha-1 alone or tank-mixed with pendimethalin (®Prowl H2O) at 1064 g ha-1. The insecticides acephate (®Orthene 90 SP) at 560 g ha-1, betacyfluthrin (®Baythroid XL) at 37 g ha-1 , dicrotophos (®Bidrin 8 E) at 448 g ai ha-1, dimethoate (®Dimethoate 4E) at 280 g ha-1, imidacloprid (®Trimax) at 53 g ai/ha-1, lambda-cyhalothrin (®Karate Z) at 37 g ha-1, oxamyl (®Vydate C-LV) at 448 g ha-1, thiamethoxam (®Centric 40 WG) at 53 g ha-1, or zeta-cypermethrin (®Mustang Max) at 25 g ai/ha were also tank-mixed with glyphosate and pendimethalin. Results indicate that visual crop response in the form of minor malformation and veinal yellowing of contacted leaves can be observed following a POST co-application of pendimethalin with glyphosate (3 to 16%). Addition of insecticides to the glyphosate plus pendimethalin mixture did not affect visual injury. Plant growth and seedcotton yield were not impacted by treatments. [ABSTRACT FROM AUTHOR]

Past research has shown that a postemergence (POST) mixture of a residual herbicide, such as Smetolachlor, with glyphosate can result in improved weed control and maximize cotton yield. Published research is limited on the tolerance of a POST mixture of an aqueous capsule suspension (ACS) formulation of pendimethalin with glyphosate applied at different growth stages to cotton. Research of this issue is important as producers continue to search for cost savings in cotton production, and the inclusion of residual herbicides such as pendimethalin in the planting regimen is needed to abate the expansion of glyphosate-resistant (GR) weeds. This research was conducted in 2006 and 2007 to evaluate the effects of POST combinations of glyphosate with an ACS formulation of pendimethalin on second-generation GR cotton growth, development, and yield. Treatments evaluated in the study included a factorial arrangement of herbicides [glyphosate (®Roundup Weathermax) at 1540 g ha-1 alone or in combination with ACS pendimethalin (®Prowl H2O) at 1064 or 2128 g ha-1 or S-metolachlor (Dual Magnum) at 1064 or 2128 g ha-1] and cotton growth stage (4- to 5- or 6- to 8-leaf). Ammonium sulfate at 2524 g ha-1 was included with each treatment. Results indicated that visual crop response in the form of veinal yellowing and slight leaf malformation can be observed following a POST tank-mixture of pendimethalin with glyphosate. Response is limited to contacted leaves. Visual crop response following mixture of glyphosate with pendimethalin was minimal 21 d after both application timings and was not manifested in reductions in plant height or seedcotton yield compared to glyphosate applied alone. [ABSTRACT FROM AUTHOR]

Agricultural weeds evolve in response to crop cultivation. Nevertheless, the central importance of evolutionary ecology for understanding weed invasion, persistence and management in agroecosystems is not widely acknowledged. This paper calls for more evolutionarily-enlightened weed management, in which management principles are informed by evolutionary biology to prevent or minimize weed adaptation and spread. As a first step, a greater knowledge of the extent, structure and significance of genetic variation within and between weed populations is required to fully assess the potential for weed adaptation. The evolution of resistance to herbicides is a classic example of weed adaptation. Even here, most research focuses on describing the physiological and molecular basis of resistance, rather than conducting studies to better understand the evolutionary dynamics of selection for resistance. We suggest approaches to increase the application of evolutionary-thinking to herbicide resistance research. Weed population dynamics models are increasingly important tools in weed management, yet these models often ignore intrapopulation and interpopulation variability, neglecting the potential for weed adaptation in response to management. Future agricultural weed management can benefit from greater integration of ecological and evolutionary principles to predict the long-term responses of weed populations to changing weed management, agricultural environments and global climate. [ABSTRACT FROM AUTHOR]

Highlights of a multidisciplinary research program on innovative weed control are presented and discussed in this paper. The program was carried out from 1999 to 2002, and dovetailed most fundamental-strategic and applied research aspects in The Netherlands in that period with respect to weed management. The program was focused on both developing and implementing sustainable weed control strategies for agricultural and non-agricultural areas. Some projects in the program were on (1) developing and improving weed preventive and non-chemical methods, (2) methods that allow the farmer to apply lower dosage of herbicides than indicated on the label, e.g. the so-called "Minimum Lethal Herbicide Dose method" (MLHD), and (3) rational weed control on hard surfaces. The main results of these projects are presented. A successful development and implementation of new methods and systems of weed control that use considerably less herbicides, is determined by many factors. The role that these success factors played in the aforementioned projects is shortly discussed. [ABSTRACT FROM AUTHOR]

Studies the real-time weed detection, decision making and patch spraying in maize, sugar beet, winter wheat and winter barley. Use of digital image analysis, computer-based decision making and global positioning systems; Measurement of the frequency of herbicide resistant and the demands for lower herbicide residues in food, water and soil.

Weed invasions are an increasing threat to the extensive wetlands of the Northern Territory's wet-dry tropics. Although the conservation value of these wetlands is in some ways undisputed, it is evident from the Government's multiple land use policy that it is also misunderstood. This policy aims to maximise economic returns from wetlands while protecting their ecological integrity at a time when ecological and economic costs associated with weeds are, at least in the short term, set to worsen. The underlying reasons behind wetland loss and degradation in Australia parallel those identified in Mediterranean Europe where there was antipathy from bureaucracies toward science and ecology. Several case studies from the Northern Territory explore how ecological, anthropogenic, political and economic factors contribute to weed problems. Caution is necessary when translating experience from agricultural weeds to environmental weeds. Managers have not always heeded the advice of specialists and practitioners, whose understanding of the ecological basis to weed invasions is not in as parlous a state as sometimes thought. Even when faced with sound information from which to manage, it was non-ecological reasons that slowed down or prevented effective weed control. If the floristic identity and diversity of Australia's natural wetlands is to be retained, then weeds need serious and immediate attention. Weed impacts progress beyond loss of wetland habitat and biodiversity to regional changes in landscape processes. We advocate that governments and industry recognise and address the underlying non-ecological reasons that exacerbate weed problems and set priorities to fund relevant practical studies and control programs that enable inventive weed management. Cooperation between land users, custodians and the wider community can help to overcome bureaucratic obstacles and enable judicious weed control that contributes effectively to wetland protection. [ABSTRACT FROM AUTHOR]

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)