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In 1925, the American entomologist Walter Sidney Abbott proposed an equation for assessing efficacy, and it is still widely used today for analysing controlled experiments in crop protection and phytomedicine. Typically, this equation is applied to each experimental unit and the efficacy estimates thus obtained are then used in analysis of variance and least squares regression procedures. However, particularly regarding the common assumptions of homogeneity of variance and normality, this approach is often inaccurate. In this tutorial paper, we therefore revisit Abbott's equation and outline an alternative route to analysis via generalized linear mixed models that can satisfactorily deal with these distributional issues. Nine examples from entomology, weed science and phytopathology, each with a different focus and methodological peculiarity, are used to illustrate the framework. [ABSTRACT FROM AUTHOR]

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]

An important reserve for increasing the productivity of agricultural production is a scientifically based crop structure and the use of rational crop rotations, which implement the optimal ratio of agroecological standards. The aim of the research was to determine the influence of elements of agrotechnical measures, in particular, the saturation of crop rotations with sunflower, soil tillage system on the number and species composition of various agrobiological groups of weeds in sunflower crops, including the weed parasite sunflower broomrape (Orobahche cumana Wallr.). Weed control measures and the spread of the parasitic weed sunflower broomrape in sunflower crops have been carried out according to the methods generally accepted in agriculture and weed science. The scheme of the experiment has been included crop rotations with saturation in the structure of sunflower sowing of 12.5%, 20%, 25%, 33.3%, 50%, 100% and three systems of basic tillage: moldboard plowing, disc tillage, no-tillage. As a result of the research, it has been found that the systems of disc tillage and no-tillage cause an increase in the number of weeds in sunflower crops compared to the moldboard plowing by 1.3-1.5 times. On average, over the years of research, the abundance of weeds in the plots when using disk tools was 10.4-15.1 pcs/m², moldboard plowing - 7.1-12.4 pcs/m², before harvesting - 2.6-5.2 and 4.1-12.4 pcs/m². The highest degree of sunflower broomrape damage has been observed in 2-fields crop rotation (winter wheat - sunflower) and permanent sunflower cultivation, as 16.0-32.4% of affected sunflower plants have been observed here. The intensity of sunflower broomrape damage to sunflower plants was higher in the moldboard plowing system and amounted to 1.2-8.3 pcs/per plant, which exceeded disc tillage and no-tillage by 1.2-1.6 times. The maximum seed yield of 2.92-2.95 t/ha has been obtained in 8- and 5- fields rotations with the use of moldboard plowing. The lowest yields of sunflower seeds were in short-rotation crop rotations with a sunflower saturation of 50% in the structure of sown areas and permanent cultivation and amounted to: moldboard plowing - 1.75-2.21 t/ha, disk tillage - 1.57-2.01 t/ha and no-tillage - 1.49-1.95 t/ha. Given the urgency of supplying the global market with sunflower oil, in the future it is necessary to increase the concentration of sunflower in the structure of sown areas to 30-40% through the system of basic tillage, selection of resistant hybrids and use of herbicides. [ABSTRACT FROM AUTHOR]

Characterizing seeds of tropical weeds is crucial for future research to understand their ability to disperse in space and time through their seeds, and building up seed banks. Seeds of 55 weed species occurring on Reunion Island were collected and characterized. Seeds were described by their shape, size, color, texture, hairiness, or particular markings. Seed traits were recorded in a database in French and English. It has been published on the CIRAD AMATROP dataverse, which centralizes datasets on tropical weeds. It will be updated as new weed seeds from tropical regions are characterized. In a long-term perspective, these data allow for creating a multicriteria identification key to identify seeds to study seed stocks in agricultural fields.

Abstract Weeds are attractive models for basic and applied research due to their impacts on agricultural systems and capacity to swiftly adapt in response to anthropogenic selection pressures. Currently, a lack of genomic information precludes research to elucidate the genetic basis of rapid adaptation for important traits like herbicide resistance and stress tolerance and the effect of evolutionary mechanisms on wild populations. The International Weed Genomics Consortium is a collaborative group of scientists focused on developing genomic resources to impact research into sustainable, effective weed control methods and to provide insights about stress tolerance and adaptation to assist crop breeding.

In recent years, a great deal of evidence has accumulated on the health risks and environmental impacts of some herbicides. Both conventional agriculture and agroecology are searching for alternatives to address the challenges posed by the consequences of herbicide use. In this search, peasant and indigenous agroecosystems have much to contribute since their crops evolved thousands of years ago together with diverse communities of weeds, and farmers have carried out sophisticated strategies to manage them. Through participant observation, semi-structured interviews, free lists, and botanical collection, we document a milpa design that integrates and manages spontaneous vegetation to take advantage of its presence and minimize risks of crop loss. The objective of this article is to critically contrast agroecological mechanisms in this milpa design which matches the prevention principle with a set of recommendations recognized as preventive in conventional weed science. [ABSTRACT FROM AUTHOR]

Introduction: In agricultural systems, several environmental stresses can remarkably alter the growth, physiological, and biochemical responses of plants under stress. One of these factors is the biochemical reactions between plants along with the production of secondary compounds. Allelochemicals mainly have defence and cell wall ligninization roles in plants and do not directly play a role in the growth processes of plants. Thus, an experiment was carried out to evaluate the effect of allelopathic stress of Hypericum perforatum on the germination, physiological, biochemical, and antioxidant activity characteristics of green pea, the benchmark plant sensitive to allelochemicals. Materials and methods: The treatments included different concentrations of H. perforatum at 11 levels (i.e., 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100% of the aqueous extract). This research was carried out as a completely randomized design with three replications at the weed science laboratory of Gonbad Kavous University in 2023. Results: The results of this study showed that one of the factors influencing the physiological, and biochemical characteristics of green pea is the concentration of the H. perforatum extract. In most cases, the percentage and rate of green pea germination, radicle and plumule length, and dry weight of radicle and plumule decreased with increased concentration of aqueous extract compared to the control, so that the greatest reduction in these characteristics was observed in 100% of H. perforatum extract. In contrast, the content of compatible osmolytes such as proline and soluble sugars, phenolic and flavonoid compounds, and antioxidant activity of green pea roots and plumules increased significantly in all studied treatments, with the highest increase in these characteristics observed at the concentration of 100% of H. perforatum aqueous extract. In general, the decrease in the dry weight of green pea seedlings due to the increase in the concentration of the aqueous extract of H. perforatum, despite the relative increase in the content of physiological and biochemical traits, indicates the high intensity of allelopathic stress of H. perforatum extract and their insufficiency, which leads to cytotoxicity against oxidative stress. Conclusion: Considering the heterotoxicity effect of H. perforatum on green pea sensitive to allelochemicals and its distribution in gardens, barren lands, and wheat and corn fields, the possible effect of their residues in the next planting and even in case of presence in mixed cultivation should be considered. [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]

Copyright of Informacion Tecnica Economica Agraria is the property of Asociacion Interprofesional para el Desarrollo Agrario (AIDA) 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.)

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]

While integrative data analysis (IDA) presents great opportunity, it also necessitates a myriad of methodological decisions related to harmonizing disparate measures collected across multiple studies. There is a lack of step-by-step methodological guidance for harmonizing disparate measures of latent constructs differently conceptualized or operationalized across studies, such as social, emotional, and behavioral constructs often utilized in prevention science. The current paper addressed this gap by providing methodological guidance and a case illustration focused on harmonizing measures of disparately conceptualized and operationalized constructs. We do so by outlining a five-phased harmonization approach paired with an illustrative example of the approach as applied to harmonization of broadband latent emotional and behavioral health constructs assessed with different measures across studies. This approach builds on and expands upon procedures currently recommended in the IDA literature with parallels to best practices in test development procedures. The illustrative example of our phased approach is drawn from an IDA study of 11 randomized controlled trials of Coping Power (Lochman & Wells, 2004), an evidence-based preventive intervention. We demonstrate the harmonization of two constructs, internalizing and externalizing problems, as harmonized across the teacher-reported scales of the Achenbach System of Empirically Based Assessment (Achenbach, 1991a) and the Behavior Assessment System for Children (Reynolds & Kamphaus, 2004). Finally, we consider the potential strengths and limitations of this phased approach, underscoring areas for future methodological research and conclude with some recommendations. [ABSTRACT FROM AUTHOR]

Omics techniques, including genomics, transcriptomics, proteomics, and metabolomics have smoothed the researcher's ability to generate hypotheses and discover various agronomically relevant functions and mechanisms, as well as their implications and associations. With a significant increase in the number of cases with resistance to multiple herbicide modes of action, studies on herbicide resistance are currently one of the predominant areas of research within the field of weed science. High-throughput technologies have already started revolutionizing the current molecular weed biology studies. The evolution of herbicide resistance in weeds (particularly via non-target site resistance mechanism) is a perfect example of a complex, multi-pathway integrationinduced response. To date, functional genomics, including transcriptomic and metabolomic studies have been used separately in herbicide resistance research, however there is a substantial lack of integrated approach. Hence, despite the ability of omics technologies to provide significant insights into the molecular functioning of weeds, using a single omics can sometimes be misleading. This mini-review will aim to discuss the current progress of transcriptome-based and metabolome-based approaches in herbicide resistance research, along with their systematic integration. [ABSTRACT FROM AUTHOR]

Objective: Review current knowledge of weed resistance to glyphosate in the México and the rest of the world. Design/methodology/approach: The bibliographic review included a systematic study based on various databases, including FAOSTAT, FAO, SIAP and Weed science. Results: With the introduction of resistant transgenic crops, the use of this herbicide has increased fifteenfold since 1996. Just in the last 26 years, 350 cases of glyphosate resistance among weeds have been reported worldwide; however, multiple resistance has been recorded in 23 weed species in 17 countries around the world. Limitations on study/implications: The knowledge generated is essential to plan strategies to reduce the use of glyphosate. Findings/conclusions: In the future, the dependence on this herbicide will result in multiple resistance among weeds, not only in Mexico, but in more parts of the world than those that have been reported to date. [ABSTRACT FROM AUTHOR]

Serotiny results in aerial seedbanks that enable persistence of some plant species by evading decay, predation, or lethal germination in the soil seedbank. Although more common in forestry, this concept has received little focus in weed science. On average, kochia [Bassia scoparia (L.) A.J. Scott] retained 2091 seeds plant-1 (~18.5% of seeds) in aerial seedbanks among 109 sample sites in spring, 7-8 months after senescence and following subsequent cohort emergence from the short-lived soil seedbank. Therefore, asynchronous seedling recruitment of kochia persisting in simultaneous aerial and soil seedbanks could represent an adaptive bet-hedging strategy for successful establishment in high-stress drought-prone environments. [ABSTRACT FROM AUTHOR]

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.)

Images from unmanned aerial vehicles (UAV) can serve as a baseline for studies in weed science, complementing observations obtained in the ground. The objective of this work was to determine soybean (Glycine max (L.) Merr.) plant injury caused by pre-emergence herbicides in sandy and clayey soils, using a low-cost UAV. The experiment was conducted in a randomized complete block design, with four replicates and seven treatments consisted of herbicides (diclosulam, chlorimuron, sulfentrazone, flumioxazin, and S-metolachlor), hand weeded and untreated treatments. Ground-based evaluations were carried out to assess soybean crop injury, plant stand, leaf chlorophyll content, plant height, canopy distance and grain yield. Images were taken using a UAV equipped with an RGB (red green and blue) camera. Soybean plants sprayed with diclosulam had lower plant reflectance in the R (98.9), G (147.1) and B (74.3) range than the other treatments in sandy soil. In clayey soil, hand weeded treatment had higher plants (30.8 cm) and untreated favored smaller plants (24.9 cm) compared to herbicide treatments. In sandy soil, soybean yield of all treatments was similar, however in clayey soil, soybean yield treated with chlorimuron and flumioxazin was higher than 5000 kg ha-1 and better than the others treatments. The nutrient-poor soil (sandy) may have aggravated the plant injury caused by herbicides and explain the lower yield observed compared to clayey soil. It was determined soybean plant injury caused by pre-emergence herbicides with the use of unmanned aerial vehicles, providing complementary results to ground-based measurements, indicating the potential of this technology for low-cost evaluations in weed science. [ABSTRACT FROM AUTHOR]

Characterizing seeds of tropical weeds is crucial for future research to understand their ability to disperse in space and time through their seeds, and building up seed banks. Seeds of 55 weed species occurring on Reunion Island were collected and characterized. Seeds were described by their shape, size, color, texture, hairiness, or particular markings. Seed traits were recorded in a database in French and English. It has been published on the CIRAD AMATROP dataverse, which centralizes datasets on tropical weeds. It will be updated as new weed seeds from tropical regions are characterized. In a long-term perspective, these data allow for creating a multicriteria identification key to identify seeds to study seed stocks in agricultural fields., (© 2024 The Author(s).)

This document is a corrigendum for an article titled "Investigating the dynamic responses of Aegilops tauschii Coss. to salinity, drought, and nitrogen stress: a comprehensive study of competitive growth and biochemical and molecular pathways." The corrigendum addresses an error in the author list, where Rashida Hameed was mistakenly listed as the second author instead of the first author. The corrected author list is provided, and the authors apologize for the error. The corrigendum does not affect the scientific conclusions of the article. [Extracted from the article]

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]

The taxonomy of Echinochloa, a predominantly tropical to warm-temperate genus of 40-50 species, including some of the world's worst weeds, is still poorly understood. This is because some species, including the extremely widespread E. crus-galli, show a wide range of morphological, physiological and ecological variation, in part the result of a complex recent evolutionary history. Furthermore, there is often a dearth of clear distinguishing features among species. The same applies to the species established in Southwestern Europe, where unintentionally introduced populations have now established themselves as important weeds of crops, especially maize and rice. Taxonomic and nomenclatural confusion hampers progress in weed science. In this study, we give an identification key that covers the weedy taxa encountered in Southwestern Europe, followed by notes on taxonomy and nomenclature. Moreover, a lectotype is designated for Echinochloa frumentacea. It is argued that current confusion cannot be overcome without including populations of Eastern Asian origin in taxonomic studies and without the joint efforts of experts in the fields of weed science, morphology-based taxonomy, genomics and phylogenetics. [ABSTRACT FROM AUTHOR]

Reports of weed resistance to herbicides have increased in recent years and differentiation in resistance mechanisms is considered to be a concern for the future of weed science. The aim of this work was to characterize the mechanisms of resistance to herbicides associated with Conyza sp. complex and analyze their implications. Aspects of the action of herbicides commonly used in their control will be addressed, in addition to a description of the mechanisms involved in multiple resistance in Conyza species. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to elucidate the roles that microbes may be playing in the rootzone of the medicinal plant Daturainoxia. We hypothesized that the microbes associated with the Datura rootzone would be significantly different than the similar surrounding fields in composition and function. We also hypothesized that rhizospheric and endophytic microbes would be associated with similar metabolic functions to the plant rootzone they inhabited. The methods employed were microbial barcoding, tests of essential oils against antibiotic resistant bacteria and other soil bacterial isolates, 16S Next Generation Sequencing (NGS) metabarcoding, and Whole Genome Shotgun (WGS) taxonomic and functional analyses. A few of the main bacterial genera of interest that were differentially abundant in the Datura root microbiome were Flavobacterium (p = 0.007), Chitinophaga (p = 0.0007), Pedobacter (p = 6 × 10−5), Bradyhizobium (p = 1 × 10−8), and Paenibacillus (p = 1.46 × 10−6). There was significant evidence that the microbes associated with the Datura rootzone had elevated function related to bacterial chalcone synthase (p = 1.49 × 10−3) and permease genes (p < 0.003). There was some evidence that microbial functions in the Datura rootzone provided precursors to important plant bioactive molecules or were beneficial to plant growth. This is important because these compounds are phyto-protective antioxidants and are precursors to many aromatic bioactive compounds that are relevant to human health. In the context of known interactions, and current results, plants and microbes influence the flavonoid biosynthetic pathways of one other, in terms of the regulation of the phenylpropanoid pathway. This is the first study to focus on the microbial ecology of the Datura rootzone. There are possible biopharmaceutical and agricultural applications of the natural interplay that was discovered during this study of the Datura inoxia rhizosphere. [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]

Pennyroyal (Mentha pulegium L.), which is among the medicinal and aromatic plants belonging to the Lamiaceae family, is a plant rich in essential oils. This study was carried out in Malatya Turgut Özal University, Faculty of Agriculture, Plant Protection Department, Weed Science laboratory in 2020 to determine the effect of pennyroyal essential oils at rates doses (0.5, 1.0, 2.0, 4.0, 8.0 and 16.0 µl petri-1) on the germination of seeds of some weeds [(Amaranthus palmeri S. Wats.), (Amaranthus albus L.), (Avena fatua L.) and (Sinapis arvensis L.)] and crops [(Capsicum annuum L.) and ((Triticum aestivum L.)]. it was found that the germination of seeds of all species was fully suppressed in 16 µl petri-1 dose application while the lowest effect (1%) was obtained from 1 µl petri-1 dose application in S. arvensis seed. According to the LD50 and LD90 values in the study, the highest dose was seen in T. aestivum as 3.520 and 7.857 µl petri-1 and the lowest dose was seen in A. palmeri seed as 0.004 and 0.175 µl petri-1 respectively. Low doses were effective in preventing the germination of A. albus and A. palmeri seeds, which are problem weeds in pepper and vegetable fields. It is thought that this result will benefit bioherbicide studies in the future. [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]

Invasive weed species in California's rangelands can reduce herbaceous diversity, forage quality and wildlife habitat. Small-scale studies (5 acres or fewer) have shown reductions of medusahead and yellow starthistle using prescribed grazing on rangelands, but little is published on the effects of pasture-scale (greater than 80 acres) prescribed grazing on weed control and plant community responses. We report the results of a 6-year collaborative study of manager-applied prescribed grazing implemented on rangeland that had not been grazed for 4 years. Grazing reduced medusahead but did not alter yellow starthistle cover. Medusahead reductions were only seen in years that did not have significant late spring rainfall, suggesting that it is able to recover from heavy grazing if soil moisture is present. Later season grazing appears to have the potential to suppress medusahead in all years. In practice, however, such grazing is constrained by livestock drinking water availability and forage quality, which were limited even in years with late spring rainfall. Thus, we expect that grazing treatments under real-world constraints would reduce medusahead only in years with little late spring rainfall. After 10 years of grazing exclusion, the ungrazed plant communities began to shift, replacing medusahead with species that have little value, such as ripgut and red brome.

The document is an audit report from the President of the Society of Southwestern Entomologists, Alvaro Romero. The report states that the financial records of the Society for the period of January 1, 2023, to December 31, 2023, are in good order and accurately reported. Alvaro Romero is an Associate Professor of Urban Entomology at New Mexico State University. [Extracted from the article]

The document is a preface from the Kultivasi Journal, Volume 23 Issue 1, published in April 2024. The journal focuses on various scientific aspects related to agriculture, including soil science, weed science, plant pests and diseases, agronomy, and plant breeding. The articles in this issue have been edited and reviewed by experienced editors and reviewers from Indonesia and overseas. The journal aims to broaden the academic understanding of agricultural practitioners and scientists and hopes to be indexed internationally in the future. The preface expresses gratitude to the readers, authors, and reviewers for their loyalty and support in developing the journal. [Extracted from the article]

Preventing plant invasions or eradicating incipient populations is much less costly than confronting large well-established populations of invasive plants. We developed a preliminary determination of plants that pose the greatest risk of becoming invasive in California, primarily through the horticultural industry. We identified 774 species that are invasive elsewhere in Mediterranean climates but not yet invasive in California. From this list, we determined which species are sold through the horticulture industry, whether they are sold in California and whether they have been reported as naturalized in California. We narrowed the list to 186 species with the greatest potential for introduction and/or invasiveness to California through the horticultural trade. This study provides a basis for determining species to evaluate further through a more detailed risk assessment that may subsequently prevent importation via the horticultural pathway. Our results can also help land managers know which species to watch for in wildlands.

Invasive and endemic weeds pose recurring challenges for California land managers. The evolution of herbicide resistance in several species has imposed new challenges in some cropping systems, and these issues are being addressed by UC Cooperative Extension farm advisors, specialists and faculty. There are currently 24 unique herbicide-resistant weed biotypes in the state, dominated by grasses and sedges in flooded rice systems and, more recently, glyphosate-resistant broadleaf and grass weeds in tree and vine systems, roadsides and glyphosate-tolerant field crops. Weed scientists address these complex issues using approaches ranging from basic physiology and genetics research to applied research and extension efforts in grower fields throughout the state. Although solutions to herbicide resistance are not simple and are affected by many biological, economic, regulatory and social factors, California stakeholders need information, training and solutions to address new weed management problems as they arise. Coordinated efforts conducted under the Endemic and Invasive Pests and Disease Strategic Initiative directly address weed management challenges in California's agricultural industries.

Worldwide, the majority of the plant species that are developing herbicide resistance are those that occur as weeds in agricultural environments, on roadsides and in other rights-of-way. In contrast, herbicide resistance is not nearly so common in weeds of natural areas or rangelands. A search of the International Survey of Herbicide Resistant Weeds ( weedscience.com ) revealed no herbicide-resistant weeds (i.e., invasive nonnative species) listed for terrestrial natural areas anywhere in the world, and only two resistant weeds listed for aquatic areas, both of them in Florida. In pastures, 15 species worldwide have developed resistance, eight of which are considered primarily as agricultural weeds. Only two of those 15 are found in pastures within the United States, and none occurs in any Western state.

Weed management systems in California vegetable crops can be described as robust, complex, multitactic and integrated. Vegetable herbicides generally make up just one component in a multicomponent weed management system. With California's seasonally dry weather and growers’ ability to control soil moisture by means of irrigation scheduling, it becomes possible for the grower to apply effective cultural and physical control practices, such as preparation of stale seedbeds and inter-row cultivation. Redundancy is designed into the weed management system to minimize weed emergence in the crop. The key tools that make up an integrated vegetable weed management system are field selection, sanitation, crop rotation, land preparation, stale seedbeds, herbicides and physical weed control (UC IPM 2009). Growers who carefully apply these practices are able to manage weeds effectively and reduce the presence of weed seeds in the soil seedbank.