The status (weed or beneficial shrub) of Chromolaena odorata in West Africa has been a major subject of debate since its introduction in the 1930s. Its negative impacts on agriculture and biodiversity are clear. However, indigenous people have harnessed several benefits of the plant, making management strategies less straightforward. Using indigenous voices in Ghana, the current perceptions of C. odorata

Development of integrated weed management strategies is dependent on a thorough knowledge of the demography of individual species. The current research established eight winter or summer weed species in a winter annual wheat cropping system at Wongan Hills, Western Australia, and investigated emergence of the first cohort of each species, survivorship, plant size, seed production and seed shedding

An experiment to investigate why glufosinate ammonium control of Lolium spp. is more effective at cooler temperatures than warmer temperatures was conducted at Welgevallen Experimental Farm, Stellenbosch University. Wild Lolium spp. was grown at 10/15, 15/20, 20/25 and 25/30°C (night and day) temperature regimes and treated with glufosinate ammonium at 0, 300, 600, 900 and 1,200 g a.i./ha, 6 weeks

The correct application of a new herbicide depends on knowledge concerning its behaviour within the cultivation system. The objective of this study was to evaluate the sorption–desorption process of aminocyclopyrachlor in soils with the addition of three aged organic materials from sugar cane and their transport via leaching. Sugar cane straw (12 t/ha), filter cake (90 t/ha) and vinasse (200 m3/ha)

Weed management using synthetic herbicides is undergoing a global decline, necessitating a re‐evaluation of existing control measures and the development of novel weed management tools. ‘Mini‐ridging’ is a non‐discriminatory, physical weeding method that functions by burying weeds in the intrarow with a laterally shifted ridge of soil. In glasshouse trials using potted plants, we found that plant recovery

Understanding drivers of weed density and diversity is essential for the development of weed management strategies. Here, we compared temporal changes in weed density and diversity under no‐till (NT) and conventional (CONV) tillage systems in cotton–maize rotations on loam, clay loam and sandy loam soils immediately after transition to NT in Kadoma, Zimbabwe. The effect of tillage system on weed density

The parasitic weed genus Striga causes huge losses to crop production in sub‐Saharan Africa, estimated to be in excess of $7 billion per year. There is a paucity of reliable distribution data for Striga; however, such data are urgently needed to understand current drivers, better target control efforts, as well as to predict future risks. To address this, we developed a methodology to enable rapid

We assessed the seed production and shedding pattern of 10 common weed species in two oat fields in Denmark. The aim was to evaluate the possibility of harvesting retained seeds on weeds at crop harvest by a combine harvester based on estimation of weed seed retention. Before flowering, ten plants of each weed species were selected and surrounded by a seed trap comprising of a porous net. When the

The globally invasive weed, mayweed chamomile (Anthemis cotula L.) is an annual, bushy, ill‐scented herb, originating in Eurasia. It is aggressively weedy in croplands, field‐side ditches, wet areas and along roadsides, especially in slightly acidic, nitrogen‐rich, clay‐loam soils. In addition to interfering with crop growth, the weed causes dermatitis and eye irritation in humans, skin rashes and

Chloris virgata is a problematic weed around the world. Prediction of weed germination rates could be a useful strategy to optimise timing of weed control actions. We studied the germination and emergence of C. virgata collected seeds under different after‐ripening treatments and different exhumation dates after seed dispersal, to estimate seed dormancy level and predict weed emergence dynamics under

A 2‐year field study was conducted to determine the effects of different nutrition systems and Salsola kali subsp. tragus densities on industrial hemp yield and its components. Experiments were conducted as a split plot in a randomised complete block design with three replicates. Factors were fertilisation (poultry manure, vermicompost and nitrogen fertiliser) as the main plot and weed density (0,

Good weed management relies on the proper timing of weed control practices in relation to weed emergence dynamics. Therefore, the development of models that predict the timing of emergence may help provide growers with tools to make better weed management decisions. The aim of this study was to validate and compare two previously published predictive empirical thermal time models of the emergence of

Euphorbia heterophylla populations endued with resistance to both imazethapyr (an acetolactate synthase inhibitor) and fomesafen (a protoporphyrinogen oxidase inhibitor) were first detected in Brazil in 2004. The objectives of this study were to determine the number and dominance of genes conferring imazethapyr and fomesafen resistance in E. heterophylla and to establish the types of inheritance of

The widespread use and increasing reliance on herbicides for weed control has resulted in a global epidemic of evolved herbicide resistance in weed populations. In response, there has been a great deal of research effort to document resistance cases, understand the genetic and physiological mechanisms of resistance and use models and model organisms to explore resistance management strategies. Here

In Argentina, Eleusine tristachya has been recently reported as a problematic weed that can occur at high densities in spring and summer in fallows and in maize and soyabean. The reason for the increase in E. tristachya populations is that once the weed is established, it is difficult to eliminate because it produces a high number of seeds and plant regrowth occurs after herbicide treatments. The aim

Characteristic arable weed species of dryland cereal fields have undergone significant declines, due to agricultural intensification, to the point that some of them are considered rare. Crop edges host higher abundances of arable weed species, therefore they may act as a refuge for the conservation of these rare arable species. Using mesocosms, we experimentally tested how conditions at field edges

Legislated pesticide‐use restrictions or bans in a growing number of countries worldwide are forcing growers and land managers to reactively plan, develop or implement alternative pest management practices and even entire farming systems. While the rapidly rising incidence of multiple resistance in weed populations had already begun this transition in many agroregions, the future pace of change will

Research and development activities on non‐chemical weed control methods to date have mainly focused on mechanical and thermal applications. Selectivity in mechanical weed control is obtained using dynamically actuated harrows. Selectivity in thermal weed control is obtained through a certain heat tolerance of the crop. In conservation agriculture (CA), weed emergence is partially suppressed by constant

Weed seeds are introduced to agronomic systems naturally or through human‐mediated seed dispersal, and introduced seeds have a high chance of being resistant to selective, in‐crop herbicides. However, colonisation (invasion) rates for a weed species are usually much lower than rates of seed dispersal. The current research investigated colonisation of a winter annual wheat cropping system in Western

Developing invasive plant management strategies is an important task in modern ecology, conservation biology and land management. Solidago gigantea is considered a problematic invader in Europe and Asia, where it forms dominant stands that can decrease species diversity. There is, therefore, an urgent need for effective management to reduce S. gigantea infestations and their negative impacts. We examined

Information on seed germination and emergence ecology of Aegilops tauschii is scant, despite it being a widespread invasive weed in China. We conducted this study to determine the effects of various factors on seed germination and seedling emergence in three A. tauschii populations. Seeds germinated across a wide range of temperatures (5–35°C), with germination of over 90% at 15–20°C. Germination was

Hordeum spp. (barley grass) and Bromus spp. (brome grass) are annual weed species that achieve long‐distance seed dispersal via attachment to sheep, but also lead to sheep carcass damage due to the penetration of seeds into animal tissues. Range expansion of invasive weed populations predicted as a consequence of climate change may be associated with an increase in seed contamination incidence globally

Agrochemicals and plastics represent a burden on natural ecosystems and there is an urgent need to introduce alternative plant protection measures that have fewer negative impacts on the environment. Replacement of plastic mulches and synthetic pesticides with their biodegradable alternatives offers a way to decrease chemical residues. Pyrolysis liquids (PL) have been suggested as easily degradable

One side effect of human activity and global climatic change is more airborne dust. This not only has undesirable effects on human health and the environment, but may also adversely affect many agricultural processes, including herbicide efficacy. This is particularly relevant in parts of the world where dust storms are common and limited rainfall means dust persists on plants for protracted periods

Five fodder crop systems of different intensity (ranging from a double annual crop of Italian ryegrass + silage maize to a permanent meadow) were adopted for 30 years in the lowlands of Northern Italy under two input levels, differing mainly in their provision of organic fertiliser (manure). Herbicides were used in the maize crops included in all systems, except the meadow. After 30 years, the weed

Schinus terebinthifolia is a dioecious tree native to South America that has become an invasive weed in Florida, southern California, southern Arizona, Texas and Hawaii and has been naturalised in over 20 countries. Biological control is considered a viable long‐term control option for S. terebinthifolia because release from natural enemies appears to be at least partly responsible for its success

Eight experiments were carried out in Denmark to determine the yield loss of spring barley due to Cirsium arvense in farmers' fields and to suggest and evaluate a novel approach for quantifying C. arvense infestation in large plots. Literature about the competitive ability of C. arvense is old, scattered and inconclusive, and existing models for estimating crop yield loss are based on data from North

Broad‐leaved dock (Rumex obtusifolius L.) is a troublesome weed that predominantly grows in pastures and grassland. We hypothesised that frequent defoliation of Rumex will, over time, result in a reduction in root weight and leaf area, to the point where the impact on grass production is negligible. In order to investigate this hypothesis, we conducted three experiments. The objective of the first

In 2014, the rust fungus Puccinia komarovii var. glanduliferae, native to the foothills of the Himalayas from Kashmir to Western Nepal, became the first fungal agent to be released into Europe for the classical biological control of a non‐native weed. The target, Impatiens glandulifera or Himalayan balsam, is a prolific invader of riparian habitats in Europe and North America. During the period 2015–2018

Impatiens glandulifera is a globally successful invader that primarily spreads along riparian habitats; however, during the last ~20 years, it has started to colonise forests, but little has been published on impacts of this recent spread. Several factors may have contributed to this phenomenon: (i) high propagule pressure from large and widespread riparian populations, (ii) extensive anthropogenic

Weeds have a great economic impact on agricultural production because they compete with crops for resources and are alternative hosts for pests, microbial pathogens and plant‐parasitic nematodes. This study aimed to investigate the susceptibility of weeds to the root‐knot nematodes Meloidogyne javanica and Meloidogyne incognita and assess the effect of aqueous weed extracts on M. javanica egg hatching

The rust fungus, Puccinia komarovii var. glanduliferae, has been introduced into the UK for biological control of the invasive weed, Impatiens glandulifera (Himalayan balsam). However, establishment of the pathogen has differed across the country, which may be partly explained by variation in plant genotype. The aim of this study was to examine whether there is a further layer of phenotypic resistance

The perennial weed, Cirsium arvense (creeping, Canada or Californian thistle), is notorious for its ability to tolerate defoliation by mowing, herbivores or herbicides. The tolerance of 36 genotypes of C. arvense was examined by establishing pairs of clonal replicates that were assigned to a clipped or unclipped treatment. Three clippings were applied from spring to early summer to simulate repeated

Soil loss from riparian areas supporting the annual invasive weed, Impatiens glandulifera (Himalayan balsam), was measured and compared with equivalent values recorded at nearby, topographically similar areas supporting perennial vegetation over a cumulative seven‐year period, along sections of two separate river systems; one in Switzerland, and one in the UK. Soil loss from colonised locations was

Clonal species may benefit from human disturbance because their vegetative fragments may be distributed via soil. Solidago canadensis is an invasive rhizomatous perennial frequently found in ruderal environments. When creating new infrastructure, digging and cutting are two main factors that may influence the spread of S. canadensis into new areas. To have a better understanding of the invasive potential

Phenotypic plasticity, which confers a fitness advantage under heterogeneous and novel environments, has been commonly suggested to contribute to the success of invasive plants in their introduced range. For example, plasticity in response to changes in light availability could facilitate invasiveness by allowing plants to both rapidly establish in unshaded, disturbed habitats, and tolerate shaded

The use of bioherbicides containing fungal active ingredients or natural fungal molecules is one of the possible solutions to reduce the use of chemical products. This paper focuses on studies of bioherbicides, including both living fungi and natural fungal molecules, published in the last 45 years, and their associated weed targets; current problems in the development of bioherbicides are also discussed

Digitaria sanguinalis is a troublesome annual weed that causes important yield losses in different crops. Despite this, there is scarce information about different aspects of its biology under field conditions. New knowledge about the establishment process of this species will be of paramount importance in order to maximise the effectiveness of weed management. The aims of this paper were to evaluate

There is a drive to improve the sustainability of agricultural systems including the biodiversity component. Cultivar mixtures offer yield benefits from the same land area, but the mechanisms behind this overyielding have not been completely worked out. One potential mechanism is improved competition with weeds. We use an experimental approach of varying barley (Hordeum vulgare L.) genotypic and phenotypic

This paper presents an overview of introduced alien plant species inhabiting natural thermal waters of Serbia. We recorded the presence of six naturalised aquatic plant species, also recognised as weeds in several regions of the world. This was the first time that Heteranthera zosterifolia (Pontederiaceae), Lemna minuta (Araceae) and Rotala rotundifolia (Lythraceae) were recorded in the aquatic ecosystems

Functional diversity of cover crop mixtures is thought to improve biomass production and weed suppression, two key agroecosystem services in organic systems. To test this hypothesis, we selected eight cover crop species belonging to four functional groups: (i) vining growing large‐seeded legumes (field pea, common vetch), (ii) erect growing small‐seeded legumes (crimson clover, squarrosum clover),

The abundance of Juncus effusus (soft rush) and Juncus conglomeratus (compact rush) has increased in coastal grasslands in Norway over recent decades, and their spread has coincided with increased precipitation in the region. Especially in water‐saturated, peaty soils, it appears from field observations that productive grasses cannot compete effectively with such rapidly growing rush plants. In autumn–winters

Drosera L. (Droseraceae) is a genus of insectivorous plants distributed worldwide with 240 species, 40 of which are found in South America. In the temperate forests of Chile and Argentina the only species present is D. uniflora. In a peat bog in Nahuel Huapi National Park, Argentina, a new species of Drosera was found in February 2018. To identify the species, we used morphological characters, and

The development of acetolactate synthase (ALS) tolerant sugar beet provides new opportunities for weed control in sugar beet cultivation. The system consists of an ALS−inhibiting herbicide (foramsulfuron + thiencarbazone‐methyl) and a herbicide‐tolerant sugar beet variety. Previously, the use of ALS‐inhibitors in sugar beet was limited due to the susceptibility of the crop to active ingredients from

Parthenium hysterophorus is a noxious invasive weed of both agricultural and natural ecosystems, spreading aggressively in Nepal. Management of this weed in Nepal has been limited, mainly because of the lack of geo‐referenced data concerning the weed's distribution. We conducted a nationwide survey of P. hysterophorus and its coleopteran biological control agent Zygogramma bicolorata from 2013 to 2016

Despite their putative invasive potential, Miscanthus taxa have been increasingly viewed as promising crops for bioenergy production. Miscanthus x giganteus is cultivated worldwide due to its high productivity, and its non‐spreading growth limits its risk of invasion. However, the genetic uniformity of its unique cultivated clone has recently been questioned. We used morphometry, nuclear microsatellites

Hairy vetch is a widely adopted cover crop in the United States. However, hairy vetch can become weedy in subsequent crops as seeds germinate after the cover crop growing season, which is largely attributed to seed dormancy. We conducted two field experiments to determine seed germination, viability and seed production phenology of two common hairy vetch cultivars in Blacksburg and Blackstone, Virginia

Invasive plants may be more plastic than non‐invasive plants and maintain high fitness under various environmental conditions. Previous studies mainly focused on the comparisons between invasive and native plants, and comparisons between highly invasive and less invasive exotic species are still relatively rare, especially for comparisons at the subspecies level. This study examined the effects of

A better understanding of weed seed production is a key element for any long‐term management allowing some weeds to shed seeds. The challenge with measuring seed production in weeds is the large effort required in terms of time and labour. For the weed species Echinochloa crus‐galli, it was tested whether the number of seeds per panicle dry weight or per panicle length can be used to estimate seed

Phelipanche ramosa (Branched broomrape) is an obligate root parasitic plant that is a major pest of oilseed rape in France. Knowledge on seed viability and dormancy under field conditions is crucial to understand how to control P. ramosa, but is as yet unknown. Our study aimed to quantify these processes with a 2‐year seed burial experiment. Two genetically distinct populations of P. ramosa were studied

Exotic plants can compete well with native species because many invasive species are considered better nutrient users in both low‐ and high‐resource environments. However, whether invasive plants can outperform native plants at all stages of invasion is not very clear. We investigated the nitrogen (N), phosphorus (P) and N:P homeostasis of an invasive Eupatorium adenophorum and a co‐occurring native

The timing of seed germination may determine the success of a weed species in an agroecosystem, and its expression is modulated by environmental conditions, but also by seed physiology and anatomy. The aims of this study were to investigate the roles of light, pericarp, dry storage and cold stratification on seed dormancy and germination in feral radish, a troublesome agricultural weed in temperate

The issue of cross‐ or multiple resistance to acetolactate synthase (ALS) inhibitors and the auxinic herbicide 2,4‐D was investigated in Papaver rhoeas L., a common and troublesome weed in winter cereals, in a broad‐scale study across four European countries. A combination of herbicide sensitivity bioassays and molecular assays targeting mutations involved in resistance was conducted on 27 populations

Reliable in‐season and in‐field tools for rapidly quantifying herbicide efficacy in dicotyledonous weeds are missing. In this study, the maximum quantum efficiency of photosystem II (Fv/Fm) of susceptible and resistant Papaver rhoeas and Stellaria media populations in response to treatments with acetolactate synthase (ALS) inhibitors were examined. Seedlings (4–6 leafs) were transplanted into the field

Biological invasions are determined by interactions between resident plant communities and exotic plants. Time of invasion and species diversity of resident plant communities may greatly affect exotic plant invasions. We assembled low‐ and high‐diversity resident plant communities by sowing seeds of four and eight grassland species, respectively, and at each of three time periods (1, 4 and 7 weeks

Recently, a new implement for controlling weeds in cereals (CombCut) has been developed. It cuts weeds in growing cereals without damaging them by using the physical differences (in height, stem thickness, straw stiffness and branching pattern) between crops and weeds. To evaluate and compare the effects of selective cutting with different timings of herbicide application on Cirsium arvense in spring

Self‐compatible (SC) plants often deposit pollen on their own stigmas before flowers open. Thus, if we find natural hybrids between a SC species and a closely related self‐incompatible (SI) species, the pollen donor is usually expected to be the SC species. However, in previous studies of naturally occurring mixed populations of invasive Cakile maritima (SI) and Cakile edentula (SC) in Australia, hybridisation

At a time when herbicide use is being challenged by the selection of herbicide‐resistant weeds, reliance on other, innovative weed control strategies is becoming increasingly necessary. However, one may question the sustainability of these novel farming practices if weeds adapt rapidly to these non‐chemical selection pressures. Although farmers and agronomists impose many selective processes through

Industrial hemp (Cannabis sativa L.) is grown in more than 30 countries for fibre, seed and flowers, and acreage of cultivation is increasing globally. Hemp has long been promoted as a crop that competes well with weeds and requires little intervention to prevent yield losses. We conducted a literature review and found little peer‐reviewed research to support this claim. We identified only three articles