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Varah A, Ahodo K, Childs DZ, Comont D, Crook L, Freckleton RP, Goodsell R, Hicks HL, Hull R, Neve P, Norris K. Acting pre-emptively reduces the long-term costs of managing herbicide resistance. Sci Rep 2024; 14:6201. [PMID: 38485959 PMCID: PMC10940647 DOI: 10.1038/s41598-024-56525-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 03/07/2024] [Indexed: 03/18/2024] Open
Abstract
Globally, pesticides improve crop yields but at great environmental cost, and their overuse has caused resistance. This incurs large financial and production losses but, despite this, very diversified farm management that might delay or prevent resistance is uncommon in intensive farming. We asked farmers to design more diversified cropping strategies aimed at controlling herbicide resistance, and estimated resulting weed densities, profits, and yields compared to prevailing practice. Where resistance is low, it is financially viable to diversify pre-emptively; however, once resistance is high, there are financial and production disincentives to adopting diverse rotations. It is therefore as important to manage resistance before it becomes widespread as it is to control it once present. The diverse rotations targeting high resistance used increased herbicide application frequency and volume, contributing to these rotations' lack of financial viability, and raising concerns about glyphosate resistance. Governments should encourage adoption of diverse rotations in areas without resistance. Where resistance is present, governments may wish to incentivise crop diversification despite the drop in wheat production as it is likely to bring environmental co-benefits. Our research suggests we need long-term, proactive, food security planning and more integrated policy-making across farming, environment, and health arenas.
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Affiliation(s)
- Alexa Varah
- Natural History Museum, Cromwell Road, London, UK.
| | - Kwadjo Ahodo
- Institute of Zoology, Zoological Society of London, Regent's Park, London, UK
| | - Dylan Z Childs
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, UK
| | - David Comont
- Department of Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Laura Crook
- Department of Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Robert P Freckleton
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, UK
| | - Rob Goodsell
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, UK
- Swedish Museum of Natural History, Stockholm, Sweden
| | - Helen L Hicks
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, UK
- School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Brackenhurst Campus, Southwell, UK
| | - Richard Hull
- Department of Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Paul Neve
- Department of Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
- Department of Plant & Environmental Sciences, University of Copenhagen, Hoejbakkegaard Alle, 2630, Taastrup, Denmark
| | - Ken Norris
- Natural History Museum, Cromwell Road, London, UK
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2
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Wei T, Jiang L, You X, Ma P, Xi Z, Wang NN. Generation of Herbicide-Resistant Soybean by Base Editing. BIOLOGY 2023; 12:biology12050741. [PMID: 37237553 DOI: 10.3390/biology12050741] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 05/28/2023]
Abstract
Weeds cause the largest yield loss in soybean production. The development of herbicide-resistant soybean germplasm is of great significance for weed control and yield improvement. In this study, we used the cytosine base editor (BE3) to develop novel herbicide-resistant soybean. We have successfully introduced base substitutions in GmAHAS3 and GmAHAS4 and obtained a heritable transgene-free soybean with homozygous P180S mutation in GmAHAS4. The GmAHAS4 P180S mutants have apparent resistance to chlorsulfuron, flucarbazone-sodium, and flumetsulam. In particular, the resistance to chlorsulfuron was more than 100 times that of with wild type TL-1. The agronomic performance of the GmAHAS4 P180S mutants showed no significant differences to TL-1 under natural growth conditions. In addition, we developed allele-specific PCR markers for the GmAHAS4 P180S mutants, which can easily discriminate homozygous, heterozygous mutants, and wild-type plants. This study demonstrates a feasible and effective way to generate herbicide-resistant soybean by using CRISPR/Cas9-mediated base editing.
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Affiliation(s)
- Tao Wei
- Tianjin Key Laboratory of Protein Sciences, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin 300071, China
- State Key Laboratory of Elemento-Organic Chemistry, Department of Chemical Biology, National Engineering Research Center of Pesticide, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Linjian Jiang
- Key Laboratory of Pest Monitoring and Green Management, MOA, Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Xiang You
- Tianjin Key Laboratory of Protein Sciences, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Pengyu Ma
- State Key Laboratory of Elemento-Organic Chemistry, Department of Chemical Biology, National Engineering Research Center of Pesticide, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Zhen Xi
- State Key Laboratory of Elemento-Organic Chemistry, Department of Chemical Biology, National Engineering Research Center of Pesticide, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Ning Ning Wang
- Tianjin Key Laboratory of Protein Sciences, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin 300071, China
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3
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Fitness of Herbicide-Resistant Weeds: Current Knowledge and Implications for Management. PLANTS 2019; 8:plants8110469. [PMID: 31683943 PMCID: PMC6918315 DOI: 10.3390/plants8110469] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 10/16/2019] [Accepted: 10/29/2019] [Indexed: 12/21/2022]
Abstract
Herbicide resistance is the ultimate evidence of the extraordinary capacity of weeds to evolve under stressful conditions. Despite the extraordinary plant fitness advantage endowed by herbicide resistance mutations in agroecosystems under herbicide selection, resistance mutations are predicted to exhibit an adaptation cost (i.e., fitness cost), relative to the susceptible wild-type, in herbicide untreated conditions. Fitness costs associated with herbicide resistance mutations are not universal and their expression depends on the particular mutation, genetic background, dominance of the fitness cost, and environmental conditions. The detrimental effects of herbicide resistance mutations on plant fitness may arise as a direct impact on fitness-related traits and/or coevolution with changes in other life history traits that ultimately may lead to fitness costs under particular ecological conditions. This brings the idea that a “lower adaptive value” of herbicide resistance mutations represents an opportunity for the design of resistance management practices that could minimize the evolution of herbicide resistance. It is evident that the challenge for weed management practices aiming to control, minimize, or even reverse the frequency of resistance mutations in the agricultural landscape is to “create” those agroecological conditions that could expose, exploit, and exacerbate those life history and/or fitness traits affecting the evolution of herbicide resistance mutations. Ideally, resistance management should implement a wide range of cultural practices leading to environmentally mediated fitness costs associated with herbicide resistance mutations.
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4
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Liu C, Scursoni JA, Moreno R, Zelaya IA, Muñoz MS, Kaundun SS. An individual-based model of seed- and rhizome-propagated perennial plant species and sustainable management of Sorghum halepense in soybean production systems in Argentina. Ecol Evol 2019; 9:10017-10028. [PMID: 31534710 PMCID: PMC6745659 DOI: 10.1002/ece3.5578] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/23/2019] [Accepted: 07/28/2019] [Indexed: 11/30/2022] Open
Abstract
Perennial plants which propagate through both seeds and rhizomes are common in agricultural and nonagricultural systems. Due to their multifaceted life cycle, few population models are available for studying such species. We constructed a novel individual-based model to examine the effects of ecological, evolutionary, and anthropogenic factors on the population dynamics of perennial species. To exemplify the application of the model, we presented a case study of an important weed, Sorghum halepense (L.) Pers. (Johnsongrass), in soybean productions in Argentina. The model encompasses a full perennial weed life cycle with both sexual (seeds) and asexual (rhizomes) propagations. The evolution of herbicide resistance was modeled based on either single genes or quantitative effects. Field experiments were conducted in the species' native environment in Argentina to parameterize the model. Simulation results showed that resistance conferred by single-gene mutations was predominantly affected by the initial frequency of resistance alleles and the associated fitness cost. Population dynamics were influenced by evolved resistance, soil tillage, and rhizome fecundity. Despite the pivotal role of rhizomes in driving the population dynamics of Johnsongrass, most herbicides target the aboveground biomass, and chemical solutions to control rhizomes are still very limited. To maintain effective (short-term) and sustainable (long-term) weed management, it is recommended to combine soil tillage with herbicide applications for suppressing the rhizomes and delaying the evolution of resistance. This novel model of seed- and rhizome-propagated plants will also be a useful tool for studying the evolutionary processes of other perennial weeds, cash crops, and invasive species.
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Affiliation(s)
- Chun Liu
- Herbicide BioscienceSyngenta LtdBracknellUK
| | - Julio A. Scursoni
- Departamento de Producción Vegetal, Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresArgentina
| | - Raúl Moreno
- Product BiologySyngenta ArgentinaBuenos AiresArgentina
| | - Ian A. Zelaya
- Product BiologySyngenta ColombiaSanta Fé de BogotáColombia
| | - María Sol Muñoz
- Departamento de Producción Vegetal, Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresArgentina
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5
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Comont D, Knight C, Crook L, Hull R, Beffa R, Neve P. Alterations in Life-History Associated With Non-target-site Herbicide Resistance in Alopecurus myosuroides. FRONTIERS IN PLANT SCIENCE 2019; 10:837. [PMID: 31297127 PMCID: PMC6607922 DOI: 10.3389/fpls.2019.00837] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 06/12/2019] [Indexed: 05/22/2023]
Abstract
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 cereal crops in North-West Europe, has evolved resistance to seven herbicide modes-of-action, making this an ideal species to examine the presence and magnitudes of such fitness costs. Here, we use two contrasting A. myosuroides phenotypes derived from a common genetic background, one with enhanced metabolism resistance to a commercial formulation of the sulfonylurea (ALS) actives mesosulfuron and iodosulfuron, and the other with susceptibility to these actives (S). Comparisons of plant establishment, growth, and reproductive potential were made under conditions of intraspecific competition, interspecific competition with wheat, and over a gradient of nitrogen deprivation. Herbicide dose response assays confirmed that the two lines had contrasting resistance phenotypes, with a 20-fold difference in resistance between them. Pleiotropic effects of resistance were observed during plant development, with R plants having a greater intraspecific competitive effect and longer tiller lengths than S plants during vegetative growth, but with S plants allocating proportionally more biomass to reproductive tissues during flowering. Direct evidence of a reproductive cost of resistance was evident in the nitrogen deprivation experiment with R plants producing 27% fewer seed heads per plant, and a corresponding 23% reduction in total seed head length. However, these direct effects of resistance on fecundity were not consistent across experiments. Our results demonstrate that a resistance phenotype based on enhanced herbicide metabolism has pleiotropic impacts on plant growth, development and resource partitioning but does not support the hypothesis that resistance is associated with a consistent reproductive fitness cost in this species. Given the continued difficulties associated with unequivocally detecting costs of herbicide resistance, we advocate future studies that adopt classical evolutionary quantitative genetics approaches to determine genetic correlations between resistance and fitness-related plant life history traits.
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Affiliation(s)
- David Comont
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
- *Correspondence: David Comont,
| | - Craig Knight
- School of Life Sciences, University of Warwick, Wellesbourne, United Kingdom
| | - Laura Crook
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
| | - Richard Hull
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
| | - Roland Beffa
- Bayer AG, CropScience Division, Frankfurt, Germany
| | - Paul Neve
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
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6
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Cousens RD, Fournier-Level A. Herbicide resistance costs: what are we actually measuring and why? PEST MANAGEMENT SCIENCE 2018; 74:1539-1546. [PMID: 29205805 DOI: 10.1002/ps.4819] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 11/30/2017] [Accepted: 12/01/2017] [Indexed: 05/12/2023]
Abstract
Despite the considerable research efforts invested over the years to measure the fitness costs of herbicide resistance, these have rarely been used to inform a predictive theory about the fate of resistance once the herbicide is discontinued. One reason for this may be the reductive focus on relative fitness of two genotypes as a single measure of differential performance. Although the extent of variation in relative fitness between resistant and susceptible plants has not been assessed consistently, we know enough about plant physiology and ecology not to reduce it to a single fixed value. Research must therefore consider carefully the relevance of the experimental environment, the life stage and the choice of metric when measuring fitness-related traits. The reason most often given for measuring the cost of resistance, prediction of the impacts of management options on population dynamics, cannot be addressed using arbitrary components of fitness or a fixed value of relative fitness. To inform management options, the measurement of traits that capture the relevant processes and the main causes of their variation are required. With an emphasis on the benefit of field experiments measured over multiple time points and seasons, we highlight examples of studies that have made significant advances in this direction. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Roger D Cousens
- School of BioSciences, The University of Melbourne, Victoria, Australia
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7
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Wu C, Davis AS, Tranel PJ. Limited fitness costs of herbicide-resistance traits in Amaranthus tuberculatus facilitate resistance evolution. PEST MANAGEMENT SCIENCE 2018; 74:293-301. [PMID: 28834134 DOI: 10.1002/ps.4706] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/10/2017] [Accepted: 08/11/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND The fitness cost of herbicide resistance (HR) in the absence of herbicide selection plays a key role in HR evolution. Quantifying the fitness cost of resistance, however, is challenging, and there exists a knowledge gap in this area. A synthetic (artificially generated) Amaranthus tuberculatus population segregating for five types of HR was subjected to competitive growth conditions in the absence of herbicide selection for six generations. Fitness costs were quantified by using a combination of phenotyping and genotyping to monitor HR frequency changes over generations. RESULTS In the absence of herbicide selection, a significant fitness cost was observed for resistance to acetolactate synthase-inhibiting herbicides, but not for resistances to atrazine (non-target-site resistance mechanism), protoporphyrinogen oxidase inhibitors, 4-hydroxyphenylpryuvate dioxygenase inhibitors or glyphosate. Glyphosate resistance was conferred by multiple mechanisms in the synthetic population, and further analysis revealed that one mechanism, amplification of the 5-enolypyruvylshikimate-3-phosphate synthase gene, did decrease in frequency. CONCLUSION Our results indicate that herbicide-resistance mitigation strategies (e.g. herbicide rotation) that rely on the existence of fitness costs in the absence of herbicide selection likely will be largely ineffective in many cases. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Chenxi Wu
- Department of Crop Sciences, University of Illinois, Urbana, IL, USA
| | - Adam S Davis
- USDA-ARS Global Change and Photosynthesis Research Unit, Urbana, IL, USA
| | - Patrick J Tranel
- Department of Crop Sciences, University of Illinois, Urbana, IL, USA
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8
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Darmency H, Colbach N, Le Corre V. Relationship between weed dormancy and herbicide rotations: implications in resistance evolution. PEST MANAGEMENT SCIENCE 2017; 73:1994-1999. [PMID: 28485118 DOI: 10.1002/ps.4611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 05/04/2017] [Accepted: 05/04/2017] [Indexed: 06/07/2023]
Abstract
It is suggested that selection for late germinating seed cohorts is significantly associated with herbicide resistance in some cropping systems. In turn, it is conceivable that rotating herbicide modes of action selects for populations with mutations for increased secondary dormancy, thus partially overcoming the delaying effect of rotation on resistance evolution. Modified seed dormancy could affect management strategies - like herbicide rotation - that are used to prevent or control herbicide resistance. Here, we review the literature for data on seed dormancy and germination dynamics of herbicide-resistant versus susceptible plants. Few studies use plant material with similar genetic backgrounds, so there are few really comparative data. Increased dormancy and delayed germination may co-occur with resistance to ACCase inhibitors, but there is no clear-cut link with resistance to other herbicide classes. Population shifts are due in part to pleiotropic effects of the resistance genes, but interaction with the cropping system is also possible. We provide an example of a model simulation that accounts for genetic diversity in the dormancy trait, and subsequent consequences for various cropping systems. We strongly recommend adding more accurate and detailed mechanistic modelling to the current tools used today to predict the efficiency of prevention and management of herbicide resistance. These models should be validated through long-term experimental designs including mono-herbicide versus chemical rotation in the field. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Henri Darmency
- Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Nathalie Colbach
- Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Valérie Le Corre
- Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, Dijon, France
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Colbach N, Darmency H, Fernier A, Granger S, Le Corre V, Messéan A. Simulating changes in cropping practices in conventional and glyphosate-resistant maize. II. Weed impacts on crop production and biodiversity. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:13121-13135. [PMID: 28386883 DOI: 10.1007/s11356-017-8796-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 03/09/2017] [Indexed: 06/07/2023]
Abstract
Overreliance on the same herbicide mode of action leads to the spread of resistant weeds, which cancels the advantages of herbicide-tolerant (HT) crops. Here, the objective was to quantify, with simulations, the impact of glyphosate-resistant (GR) weeds on crop production and weed-related wild biodiversity in HT maize-based cropping systems differing in terms of management practices. We (1) simulated current conventional and probable HT cropping systems in two European regions, Aquitaine and Catalonia, with the weed dynamics model FLORSYS; (2) quantified how much the presence of GR weeds contributed to weed impacts on crop production and biodiversity; (3) determined the effect of cultural practices on the impact of GR weeds and (4) identified which species traits most influence weed-impact indicators. The simulation study showed that during the analysed 28 years, the advent of glyphosate resistance had little effect on plant biodiversity. Glyphosate-susceptible populations and species were replaced by GR ones. Including GR weeds only affected functional biodiversity (food offer for birds, bees and carabids) and weed harmfulness when weed effect was initially low; when weed effect was initially high, including GR weeds had little effect. The GR effect also depended on cultural practices, e.g. GR weeds were most detrimental for species equitability when maize was sown late. Species traits most harmful for crop production and most beneficial for biodiversity were identified, using RLQ analyses. None of the species presenting these traits belonged to a family for which glyphosate resistance was reported. An advice table was built; the effects of cultural practices on crop production and biodiversity were synthesized, explained, quantified and ranked, and the optimal choices for each management technique were identified.
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Affiliation(s)
- Nathalie Colbach
- Agroécologie, AgroSup Dijon, INRA, University Bourgogne Franche-Comté, F-21000, Dijon, France.
- INRA, UMR1347 Agroécologie, BP 86510, 17 rue Sully, F-21065, Dijon, France.
| | - Henri Darmency
- Agroécologie, AgroSup Dijon, INRA, University Bourgogne Franche-Comté, F-21000, Dijon, France
| | - Alice Fernier
- Agroécologie, AgroSup Dijon, INRA, University Bourgogne Franche-Comté, F-21000, Dijon, France
| | - Sylvie Granger
- Agroécologie, AgroSup Dijon, INRA, University Bourgogne Franche-Comté, F-21000, Dijon, France
| | - Valérie Le Corre
- Agroécologie, AgroSup Dijon, INRA, University Bourgogne Franche-Comté, F-21000, Dijon, France
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10
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Colbach N, Fernier A, Le Corre V, Messéan A, Darmency H. Simulating changes in cropping practises in conventional and glyphosate-tolerant maize. I. Effects on weeds. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:11582-11600. [PMID: 28324251 DOI: 10.1007/s11356-017-8591-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 02/06/2017] [Indexed: 05/09/2023]
Abstract
Herbicide-tolerant (HT) crops such as those tolerant to glyphosate simplify weed management and make it more efficient, at least at short-term. Overreliance on the same herbicide though leads to the spread of resistant weeds. Here, the objective was to evaluate, with simulations, the impact on the advent of glyphosate resistance in weeds of modifications in agricultural practises resulting from introducing HT maize into cropping systems. First, we included a single-gene herbicide resistance submodel in the existing multispecific FLORSYS model. Then, we (1) simulated current conventional and probable HT cropping systems in two European regions, Aquitaine and Catalonia, (2) compared these systems in terms of glyphosate resistance, (3) identified pertinent cultural practises influencing glyphosate resistance, and (4) investigated correlations between cultural practises and species traits, using RLQ analyses. The simulation study showed that, during the analysed 28 years, (1) glyphosate spraying only results in glyphosate resistance in weeds when combined with other cultural factors favouring weed infestation, particularly no till; (2) pre-sowing glyphosate applications select more for herbicide resistance than post-sowing applications on HT crops; and (3) glyphosate spraying selects more for species traits avoiding exposure to the herbicide (e.g. delayed early growth, small leaf area) or compensating for fitness costs (e.g. high harvest index) than for actual resistance to glyphosate, (4) actual resistance is most frequent in species that do not avoid glyphosate, either via plant size or timing, and/or in less competitive species, (5) in case of efficient weed control measures, actual resistance proliferates best in outcrossing species. An advice table was built, with the quantitative, synthetic ranking of the crop management effects in terms of glyphosate-resistance management, identifying the optimal choices for each management technique.
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Affiliation(s)
- Nathalie Colbach
- Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France.
- INRA, UMR1347 Agroécologie, BP 86510, 17 rue Sully, F-21065, Dijon, France.
| | - Alice Fernier
- Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
| | - Valérie Le Corre
- Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
| | | | - Henri Darmency
- Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
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