Paul Neve

University of Copenhagen · Plant & Environmental Sciences

Globally, weedy plants result in more crop yield loss than plant pathogens and insect pests combined. Much of the success of weeds rests with their ability to rapidly adapt in the face of human-mediated environmental management and change. The evolution of resistance to herbicides is an emblematic example of this rapid adaptation. Here, we focus on...

Genomic-based epidemiology can provide insight into the origins and spread of herbicide resistance mechanisms in weeds. We used kochia (Bassia scoparia) populations resistant to the herbicide glyphosate from across western North America to test the alternative hypotheses that 1) a single EPSPS gene duplication event occurred initially in the Centra...

The global invasion, and subsequent spread and evolution of weeds provides unique opportunities to address fundamental questions in evolutionary and invasion ecology. Amaranthus palmeri is a widespread glyphosate‐resistant (GR) weed in the USA. Since 2015, GR populations of A. palmeri have been confirmed in South America, raising questions about in...

Following growers’ reports of herbicide control problems, populations of 30 wild oats, Avena fatua, were collected from the south-east main arable counties of Ireland in 2016 and investigated for the occurrence and potential for herbicide resistance to acetyl-CoA carboxylase (ACCase) inhibitors pinoxaden, propaquizafop and cycloxydim, as well as ac...

The evolution of resistance to pesticides in agricultural systems provides an opportunity to study the fitness costs and benefits of novel adaptive traits. Here, we studied a population of Amaranthus tuberculatus (common waterhemp), which has evolved resistance to glyphosate. The growth and fitness of seed families with contrasting levels of glypho...

Antibiotic concentrations vary dramatically in the body and the environment. Hence, understanding the dynamics of resistance evolution along antibiotic concentration gradients is critical for predicting and slowing the emergence and spread of resistance. While it has been shown that increasing the concentration of an antibiotic slows resistance evo...

The adoption of site‐specific weed management (SSWM) technologies by farmers is not aligned with the scientific achievements in this field. While scientists have demonstrated significant success in real‐time weed identification, phenotyping and accurate weed mapping by using various sensors and platforms, the integration by farmers of SSWM and weed...

The evolution of resistance to pesticides in agricultural systems provides an opportunity to study the fitness costs and benefits of novel adaptive traits. Here, we studied a population of Amaranthus tuberculatus (common waterhemp), which has evolved resistance to glyphosate. Following the production of seed families with contrasting levels of glyp...

BACKGROUND Alopecurus myosuroides (blackgrass) is a major weed in Europe with known resistance to multiple herbicide modes of action. In the UK, there is evidence that blackgrass has undergone a range expansion. In this paper, genotyping‐by‐sequencing and population‐level herbicide resistance phenotypes are used to explore spatial patterns of selec...

In weed science and management, models are important and can be used to better understand what has occurred in management scenarios, to predict what will happen and to evaluate the outcomes of control methods. To-date, perspectives on and the understanding of weed models have been disjointed, especially in terms of how they have been applied to adv...

The capability of synthetic pesticides to manage weeds, insect pests and pathogens in crops has diminished due to evolved resistance. Sustainable management is thus becoming more challenging. Novel solutions are needed and, given the ubiquity of biologically active secondary metabolites in nature, such compounds require further exploration as leads...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Intense selection by pesticides and antibiotics has resulted in a global epidemic of evolved resistance. In agriculture and medicine, using mixtures of compounds from different classes is widely accepted as optimal resistance management. However, this strategy may promote the evolution of more generalist resistance mechanisms. Here we test this hyp...

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 organism...

In 2019, the ENDURE network launched a survey on the agricultural use of glyphosate in European countries. This report presents the results obtained through the survey and proposes a framework for understanding and monitoring glyphosate uses. The share of herbicides among all pesticide sales varies from one country to another. It is particularly hi...

Modeling the sustainability and economics of stacked herbicide-tolerant traits and early weed management strategy for waterhemp (Amaranthus tuberculatus) control – ERRATUM - Volume 68 Issue 2 - Chun Liu, Paul Neve, Les Glasgow, R. Joseph Wuerffel, Micheal D. K. Owen, Shiv S. Kaundun

Diversity is key for sustainable weed management and can be achieved via both chemical and non-chemical control tactics. Genetically modified crops with two-way or three-way stacked herbicide-tolerant traits allow use of herbicide mixtures which would otherwise be phytotoxic to the crop. Early Weed Management (EWM) strategies promote the use of pre...

Pesticides have underpinned significant improvements in global food security, albeit with associated environmental costs. Currently, the yield benefits of pesticides are threatened as overuse has led to wide-scale evolution of resistance. Despite this threat, there are no large-scale estimates of crop yield losses or economic costs due to resistanc...

The evolution of resistance to herbicides is a classic example of rapid contemporary adaptation in the face of a novel environmental stress. Evolutionary theory predicts that selection for resistance will be accompanied by fitness trade-offs in environments where the stress is absent. Alopecurus myosuroides, an autumn-germinating grass weed of cere...

The human‐directed, global selection for glyphosate resistance in weeds has revealed a fascinating diversity of evolved resistance mechanisms, including herbicide sequestration in the vacuole, a rapid cell death response, nucleotide polymorphisms in the herbicide target (5‐enolpyruvylshikimate‐3‐phosphate synthase, EPSPS) and increased gene copy nu...

The evolution of resistance to herbicides is a striking example of rapid, human‐directed adaptation with major consequences for food production. Most studies of herbicide resistance are performed reactively and focus on post hoc determination of resistance mechanisms following the evolution of field resistance. If the evolution of resistance can be...

Poverty brome (Bromus sterilis L.) [sterile or barren brome, syn. Anisantha sterilis (L.) Nevski] is a problematic UK arable weed. There are currently no confirmed cases of glyphosate resistance in any weed species in the United Kingdom or in B. sterilis worldwide. However, there are reports of poor control by glyphosate in this species. Here, we r...

Data S1. Materials and methods. Table S1. The 124 pre‐submitted research questions that address fundamental and applied issues in weed ecology, evolution and management

There is a pressing need for novel control techniques in agricultural weed management. Direct genetic control of agricultural pests encompasses a range of techniques to introduce and spread novel, fitness‐reducing genetic modifications through pest populations. Recently, the development of CRISPR‐Cas9 gene editing has brought these approaches into...

Durable crop protection is an essential component of current and future food security. However, the effectiveness of pesticides is threatened by the evolution of resistant pathogens, weeds and insect pests. Pesticides are mostly novel synthetic compounds, and yet target species are often able to evolve resistance soon after a new compound is introd...

Figure S1. Fresh biomass of (a) Rothamsted (HS) plants following exposure to a range of biotic and abiotic stress treatments; (b) field‐sourced NTSR plants; and (c) experimentally selected NTSR plants. Figure S2. Stress inducibility of orthologous genes in (a) Arabidopsis thaliana; and (b) Oryza sativa corresponding to the top 10 upregulated NTSR...

Table S1. Treatment programme used to experimentally select for fenoxaprop resistance in blackgrass grown in outdoor containers, starting with the Rothamsted HS population in 1990. Table S2. Herbicide resistance testing regime used with a range of graminicides on blackgrass repeatedly selected for using pendimethalin (PEND) and fenoxaprop (FEN)....

Dataset S1. Differential abundance and characterisation of leaf (a) and stem (b) proteins across NTSR populations and HS stress treatments compared with the HS control.

Methods S1. Supplementary materials.

There have been previous calls for, and efforts focused on, realizing the power and potential of weed genomics for better understanding of weeds. Sustained advances in genome sequencing and assembly technologies now make it possible for individual research groups to generate reference genomes for multiple weed species at reasonable costs. Here, we...

Grass weeds affect arable crops throughout the world, inflicting yield penalties, reducing crop quality and taking available nutrients away from the growing crop. Recently in Ireland, the presence of herbicide resistance in grass weeds has been noted. In order to preserve the sustainability of crop production in Ireland, an integrated pest manageme...

Weedy plants pose a major threat to food security, biodiversity, ecosystem services and consequently to human health and wellbeing. However, many currently used weed management approaches are increasingly unsustainable. To address this knowledge and practice gap, in June 2014, 35 weed and invasion ecologists, weed scientists, evolutionary biologist...

Herbicide resistance in grass weeds is now one of the greatest threats to sustainable cereal production in Northern Europe. Multiple herbicide resistance (MHR), a poorly understood multigenic and quantitative trait, is particularly problematic as it provides tolerance to most classes of chemistries currently used for post‐emergence weed control. Us...

Repeated use of xenobiotic chemicals has selected for the rapid evolution of resistance threatening health and food security at a global scale. Strategies for preventing the evolution of resistance include cycling and mixtures of chemicals and diversification of management. We currently lack large-scale studies that evaluate the efficacy of these d...

Should the declining diversity of weed communities in conventionally managed arable fields be regarded as a problem? The answer to this question has tended to divide researchers into those whose primary focus is on conserving farmland biodiversity and those whose goals are dictated by weed control and maximising yield. Here, we argue that, regardle...

Developmental responses to auxin are regulated by facilitated uptake and efflux, but detailed molecular understanding of the carrier proteins is incomplete. We have used pharmacological tools to explore the chemical space that defines substrate preferences for the auxin uptake carrier AUX 1. Total and partial loss‐of‐function aux1 mutants were asse...

The opportunity to target weed seeds during grain harvest was established many decades ago following the introduction of mechanical harvesting and the recognition of high weed seed retention levels at crop maturity; however, this opportunity remained largely neglected until more recently. The introduction and adoption of harvest weed seed control (...

One of the increasingly widespread mechanisms of resistance to the herbicide glyphosate is copy number variation (CNV) of the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene. EPSPS gene duplication has been reported in eight weed species, ranging from 3-5 extra copies to more than 150 extra copies. In the case of Palmer amaranth (Amaranthu...

Background: Because of site-specific effects and outcomes, it is often difficult to know whether a management strategy for the control of pests has worked or not. Population dynamics of pests are typically spatially and temporally variable. Moreover interventions at the scale of individual fields or farms are essentially unreplicated experiments:...

Glyphosate use in the United Kingdom has more than doubled in the last 20 years. Much of this increase is driven by efforts to control herbicide resistant weeds, particularly Alopecurus myosuroides, prior to crop drilling. There is precedent for evolution of glyphosate resistance in similar situations, raising concerns over the sustainability of gl...

Transdisciplinary weed research (TWR) is a promising path to more effective management of challenging weed problems. We define TWR as an integrated process of inquiry and action that addresses complex weed problems in the context of broader efforts to improve economic, environmental and social aspects of ecosystem sustainability. TWR seeks to integ...

Seed-attacking microorganisms have an undefined potential for management of the weed seedbank, either directly through inundative inoculation of soils with effective pathogenic strains, or indirectly by managing soils in a manner that promotes native seed-decaying microorganisms. However, research in this area is still limited and not consistently...

Background: Simulation models are useful tools for predicting and comparing the risk of herbicide resistance in weed populations under different management strategies. Most existing models assume a monogenic mechanism governing herbicide resistance evolution. However, growing evidence suggests that herbicide resistance is often inherited in a poly...

Ring closing metathesis (RCM) reactions of α-methylene-β-lactams are used to construct strained 11- and 12-membered macrocycles that mimic key structural elements of phyllostictine A. The highest yield and stereoselectivity was achieved making 12-membered macrocycle Z-19 with use of a p-methoxyphenyl group on the lactam nitrogen. Interestingly, sub...

Two broad aims drive weed science research: improved management and improved understanding of weed biology and ecology. In recent years, agricultural weed research addressing these two aims has effectively split into separate subdisciplines despite repeated calls for greater integration. Although some excellent work is being done, agricultural weed...

In rapidly changing environments, selection history may impact the dynamics of adaptation. Mutations selected in one environment may result in pleiotropic fitness trade-offs in subsequent novel environments, slowing the rates of adaptation. Epistatic interactions between mutations selected in sequential stressful environments may slow or accelerate...

Hydrotime threshold models are used to describe the dynamics of seed germination in response to reduced water availability. Although these models provide several biologically relevant parameters, it is unclear which statistical technique is best suited to their estimation. Most commonly, these models are fitted to the observed cumulative proportion...

Computer simulation modelling is an essential aid in building an integrated understanding of how different factors interact to affect the evolutionary and population dynamics of herbicide resistance, and thus help predict and manage how it will impact agricultural systems. In this review, we first discuss why computer simulation modelling is such a...

The potential for human-driven evolution in economically and environmentally important organisms in medicine, agriculture and conservation management is now widely recognised. The evolution of herbicide resistance in weeds is a classic example of rapid adaptation in the face of human-mediated selection. Management strategies that aim to slow or pre...

Understanding the effects of sex and migration on adaptation to novel environments remains a key problem in evolutionary biology. Using a single-cell alga Chlamydomonas reinhardtii, we investigated how sex and migration affected rates of evolutionary rescue in a sink environment, and subsequent changes in fitness following evolutionary rescue. We s...

Herbicide-resistant barnyardgrass has become widespread in the rice production systems of the midsouthern United States, leaving few effective herbicide options for controlling this weed. The acetolactate synthase (ALS)- and acetyl-CoA carboxylase (ACCase)-inhibiting herbicides remain largely effective in Clearfield® rice production, but strategies...

Synthetic herbicides have been used globally to control weeds in major field crops. This has imposed a strong selection for any trait that enables plant populations to survive and reproduce in the presence of the herbicide. Herbicide resistance in weeds must be minimized because it is a major limiting factor to food security in global agriculture....

Chenopodium album seedling emergence studies were conducted at nine European and two North American locations comparing local populations with a common population from Denmark. It is hypothesized that C. album seedling recruitment timing and magnitude have adapted to environmental and cropping system practices of a locality. Limitations in the habi...

Enhanced understanding of soil disturbance effects on weed seedling recruitment will help guide improved management approaches. Field experiments were conducted at 16 site-years at 10 research farms across Europe and North America to (i) quantify superficial soil disturbance (SSD) effects on Chenopodium album emergence and (ii) clarify adaptive eme...

Glyphosate-resistant (GR) weeds have been a prime challenge to the sustainability of GR cotton-based production systems of the midsouthern United States. Barnyardgrass is known to be a high-risk species for evolving herbicide resistance, and a simulation model was developed for understanding the likelihood of glyphosate resistance evolution in this...

The widespread evolution of resistance to herbicides is a pressing issue in global agriculture. Evolutionary principles and practices are key to the management of this threat to global food security. The application of mixtures of herbicides has been advocated as an anti‐resistance strategy, without substantial empirical support for its validation....

Cycling pesticides has been proposed as a means of retarding the evolution of resistance, but its efficacy has rarely been empirically tested. We evolved populations of in the presence of three herbicides: atrazine, glyphosate and carbetamide. Populations were exposed to a weekly, biweekly and triweekly cycling between all three pairwise combinatio...

The interaction between environment and genetic traits under selection is the basis of evolution. In this study, we have investigated the genetic basis of herbicide resistance in a highly characterized initially herbicide-susceptible Lolium rigidum population recurrently selected with low (below recommended label) doses of the herbicide diclofop-me...

The spread of herbicide resistance in barnyardgrass (Echinochloa crus-galli (L.) Beauv.) poses a serious threat to crop production in the southern United States. A thorough knowledge of the biology of barnyardgrass is fundamental for designing effective resistance-management programmes. In the present study, seed production of barnyardgrass in resp...

Pleiotropic fitness trade-offs will be key determinants of the evolutionary dynamics of selection for pesticide resistance. However, for herbicide resistance, empirical support for a fitness cost of resistance is mixed, and it is therefore also questionable what further ecological trade-offs can be assumed to apply to herbicide resistance. Here, we...

Se utilizó un modelo de simulación para explorar opciones de manejo que mitiguen los riesgos de evolución de resistencia al glyphosate en Amaranthus palmeri en algodón resistente al glyphosate en el sur de los EE UU. Nuestro primer análisis compara los riesgos de evolución de resistencia al glyphosate para siete estrategias de manejo de malezas en...

Plants exhibit a number of adaptive defence traits that endow resistance to past and current abiotic and biotic stresses. It is generally accepted that these adaptations will incur a cost when plants are not challenged by the stress to which they have become adapted--the so-called 'cost of adaptation'. The need to minimise or account for allelic va...

Neve P, Norsworthy JK, Smith KL & Zelaya IA (2011). Modelling evolution and management of glyphosate resistance in Amaranthus palmeri. Weed Research51, 99–112. A population-based model was developed to simulate the evolution of glyphosate resistance in populations of Amaranthus palmeri. Model parameters were derived from published and unpublished s...

Predictions based on evolutionary theory suggest that the adaptive value of evolved herbicide resistance alleles may be compromised by the existence of fitness costs. There have been many studies quantifying the fitness costs associated with novel herbicide resistance alleles, reflecting the importance of fitness costs in determining the evolutiona...

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 evoluti...

Surviving rigid ryegrass plants were collected from a cropping field at Pindar, Western Australia (population WALR 50), after inadequate control by glyphosate applied at the normal field rate. Plants were grown to maturity in pots and seeds were collected. Glyphosate dose–response experiments with known susceptible and resistant control populations...

1. In some cases, evaluation of resource competitive interactions between herbicide resistant vs. susceptible weed ecotypes provides evidence for the expression of fitness costs associated with evolved herbicide-resistant gene traits. Such fitness costs impact in the ecology and evolutionary trajectory of resistant populations. 2. Neighbourhood exp...

A simulation model is used to explore the influence of biological, ecological, genetic and operational (management) factors on the probability and rate of glyphosate resistance in model weed species. Glyphosate use for weed control prior to crop emergence is associated with low risks of resistance. These low risks can be further reduced by applying...

Summary Climate change could potentially impact the weed species communities found in the UK arable landscape and their ecosystem functions. A new three year project is introduced that will combine detailed mechanistic models of weed germination, competition and seedbank dynamics with a regional stochastic weather generator. The integrated model wi...

Evolved resistance to herbicides is a classic example of ‘evolution in action’. This paper calls for a greater integration of ‘evolutionary-thinking’ into herbicide resistance research. This integration, it is argued, should lead weed scientists to become less focused on simply describing resistance and more driven towards a deeper understanding of...

Repeated use of glyphosate has resulted in evolution of glyphosate-resistant Lolium rigidum populations in Australia. The relative growth, competitiveness and reproductive output of glyphosate resistant (R) and susceptible (S) L. rigidum phenotypes from a single population were compared in competition with wheat. Vegetative growth of R and S indivi...

The frequency of phenotypic resistance to herbicides in previously untreated weed populations and the herbicide dose applied to these populations are key determinants of the dynamics of selection for resistance. In total, 31 Lolium rigidum populations were collected from sites with no previous history of exposure to herbicides and where there was l...

Costs of resistance are predicted to reduce plant productivity in herbicide-resistant weeds. Lolium rigidum herbicide-susceptible individuals (S), individuals possessing cytochrome P450-based herbicide metabolism (P450) and multiple resistant individuals possessing a resistant ACCase and enhanced cytochrome P450 metabolism (ACCase/P450) were grown...

There has been much debate regarding the potential for reduced rates of herbicide application to accelerate evolution of herbicide resistance. We report a series of experiments that demonstrate the potential for reduced rates of the acetyl-co enzyme A carboxylase (ACCase)-inhibiting herbicide diclofop-methyl to rapidly select for resistance in a su...

Quantification of fitness differences between herbicide‐resistant and herbicide‐susceptible weeds permits better prediction of herbicide resistance, and the design of weed management strategies to exploit those traits that result in reduced ecological performance. Reported here is the first attempt to compare the germination and seedling emergence...

1. Quantification of fitness differences between herbicide-resistant and herbicide-susceptible weeds permits better prediction of herbicide resistance, and the design of weed management strategies to exploit those traits that result in reduced ecological performance. Reported here is the first attempt to compare the germination and seedling emergen...

Glyphosate is a key component of weed control strategies in Australia and worldwide. Despite widespread and frequent use, evolved resistance to glyphosate is rare. A herbicide resistance model, parameterized for Lolium rigidum has been used to perform a number of simulations to compare predicted rates of evolution of glyphosate resistance under pas...

Despite frequent use for the past 25 years, resistance to glyphosate has evolved in few weed biotypes. The propensity for evolution of resistance is not the same for all herbicides, and glyphosate has a relatively low resistance risk. The reasons for these differences are not entirely understood. A previously published two-herbi-cide resistance mod...

SummaryA simulation study was conducted to examine the effect of pattern of herbicide use on development of resistance to two herbicides with different modes of action in finite weed populations. The effects of the size of the treatment area (analogous to initial weed population), germination fraction and degree of self-pollination in the weed were...

This paper reviews the current state of knowledge of the ecological and population genetics of herbicide resistance. We argue that increases in the understanding and ultimately management of resistance can be achieved by studying the processes which result in resistance, prior to, and during the early stages of evolution. In particular, we consider...