Modeling the sustainability and economics of stacked herbicide-tolerant traits and early weed management strategy for waterhemp (Amaranthus tuberculatus) control

AbstractDiversity is key for sustainable weed management and can be achieved via both chemical and nonchemical control tactics. Genetically modified crops with two-way or three-way stacked herbicide-tolerant traits allow use of herbicide mixtures that would otherwise be phytotoxic to the crop. Early weed management (EWM) strategies promote the use of PRE herbicides with residual activity to keep the field free of weeds early in the season for successful crop establishment. To evaluate the respective sustainability and practicality of the two chemical-based management tactics (i.e., stacked traits and EWM), we used a population model of waterhemp, Amaranthus tuberculatus (Moq.) Sauer (syn. rudis), to simulate the evolution of resistance in this key weed species in midwestern U.S. soybean [Glycine max (L.) Merr.] agroecosystems. The model tested scenarios with a varying number of herbicide sites of action (SOAs), application timings (PRE and POST), and preexisting levels of resistance. Results showed that both tactics provided opportunity for controlling resistant A. tuberculatus populations. In general, each pass over the field should include at least two effective herbicide SOAs. Nevertheless, the potential evolution of cross-resistance may void the weed control programs embraced by stacked traits and diverse herbicide SOAs. Economic calculations suggested that the diversified programs could double long-term profitability when compared to the conventional system, because of improved yield and grain quality. Ultimately, the essence of a sustainable herbicide resistance management strategy is to be proactive. Although a herbicide-dominated approach to diversifying weed management has been prevalent, the increasing presence of weed populations with multiple resistance means that finding herbicides to which weed populations are still susceptible is becoming increasingly difficult, and thus the importance of reintroducing cultural and mechanical practices to support herbicides must be recognized.

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Changes in Herbicide Use Patterns and Production Practices Resulting from Glyphosate-Resistant Crops

Weed Technology ◽

10.1614/wt-04-189.1 ◽

2006 ◽

Vol 20 (2) ◽

pp. 301-307 ◽

Cited By ~ 161

Author(s):

Bryan G. Young

Keyword(s):

Weed Management ◽

Management Strategy ◽

Crop Production ◽

Large Scale ◽

Resistance Management ◽

Use Patterns ◽

No Till ◽

Production Practices ◽

Sites Of Action ◽

Herbicide Use

Recent shifts in herbicide use patterns can be attributed to rapid, large-scale adoption of glyphosate-resistant soybean and cotton. A dramatic increase in glyphosate use is the most obvious change associated with the adoption of glyphosate-resistant crops. Consequently, the diversity of herbicides used for weed management in these crops has declined, particularly in soybean. To date, the availability of glyphosate-resistant corn has limited the use of glyphosate in corn. While exploiting the benefits of glyphosate-resistant crops, many growers have abandoned the principles of sound weed and herbicide-resistance management. Instead of incorporating glyphosate into a resistance management strategy utilizing multiple herbicide sites of action, many growers rely exclusively upon glyphosate for weed control. Although it is difficult to establish a clear relationship between the adoption of glyphosate-resistant crops and changes in other crop production practices, the increase in no-till and strip-till production of cotton and soybean between 1995 and 2002 may have been facilitated by glyphosate-resistant crops.

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Cross Resistance to Diquat in Glyphosate/Paraquat-Resistant Conyza bonariensis and Conyza canadensis and Confirmation of 2,4-D Resistance in Conyza bonariensis

Weed Technology ◽

10.1017/wet.2021.11 ◽

2021 ◽

pp. 1-22

Author(s):

Marcelo L. Moretti ◽

Lucas K. Bobadilla ◽

Bradley D. Hanson

Keyword(s):

Management Strategies ◽

Resistance Management ◽

Cross Resistance ◽

Similar Response ◽

Weed Species ◽

Conyza Bonariensis ◽

Whole Plant ◽

Site Of Action ◽

Target Site Resistance ◽

Sites Of Action

Abstract Hairy fleabane and horseweed are pervasive weed species in agriculture. Glyphosate-resistant (GR) and glyphosate-paraquat-resistant (GPR) biotypes challenge current management strategies. These GR and GPR biotypes have non-target-site-resistance (NTSR), which can confer resistance to herbicides with different sites of action. This study’s objective was to characterize the response of GR, GPR, and glyphosate-paraquat-susceptible (GPS) biotypes of both Conyza spp. to herbicides with a different site of action. Whole-plant dose-response bioassays indicated a similar response among tested biotypes of both Conyza spp. to rimsulfuron, dicamba, hexazinone, glufosinate, flumioxazin, saflufenacil, or mesotrione. The C. bonariensis GR and GPR biotypes were 2.7- and 2.9-fold resistant to 2,4-D relative to the GPS biotype (GR50 766.7 g ai ha-1), confirming 2,4-D resistance in C. bonariensis for the first time in California. The GR and GPR biotypes were not cross-resistant to dicamba. No differences in response to 2,4-D were observed among C. canadensis biotypes with a GR50 ranging from 150.2 to 277.4 g ai ha-1. The GPR biotypes of both species were cross-resistant to diquat with a 44.0-fold resistance in C. bonariensis (GR50 863.7 g ai ha-1) and 15.6-fold resistance in C. canadensis (GR50 563.1 g ai ha-1). The confirmation of multiple resistances to glyphosate, paraquat, and 2,4-D in C. bonariensis curtails herbicide site of action alternatives and jeopardizes resistance management strategies based on herbicide rotation and tank-mixtures, underscoring the critical need for non-chemical weed control alternatives.

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Modeling the sustainability and economics of stacked herbicide-tolerant traits and early weed management strategy for waterhemp (Amaranthus tuberculatus) control – ERRATUM

Weed Science ◽

10.1017/wsc.2020.20 ◽

2020 ◽

Vol 68 (2) ◽

pp. 195-196 ◽

Cited By ~ 1

Author(s):

Chun Liu ◽

Paul Neve ◽

Les Glasgow ◽

R. Joseph Wuerffel ◽

Micheal D. K. Owen ◽

...

Keyword(s):

Weed Management ◽

Management Strategy ◽

Herbicide Tolerant ◽

Amaranthus Tuberculatus

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Weeds Hosting the Soybean Cyst Nematode (Heterodera glycines Ichinohe): Management Implications in Agroecological Systems

Agronomy ◽

10.3390/agronomy11010146 ◽

2021 ◽

Vol 11 (1) ◽

pp. 146

Author(s):

Leonardo F. Rocha ◽

Karla L. Gage ◽

Mirian F. Pimentel ◽

Jason P. Bond ◽

Ahmad M. Fakhoury

Keyword(s):

Weed Management ◽

Soybean Cyst Nematode ◽

Heterodera Glycines ◽

Integrated Management ◽

Cropping System ◽

Cyst Nematode ◽

Weed Species ◽

Initial Inoculum ◽

Herbicide Resistant ◽

Sites Of Action

The soybean cyst nematode (SCN; Heterodera glycines Ichinohe) is a major soybean-yield-limiting soil-borne pathogen, especially in the Midwestern US. Weed management is recommended for SCN integrated management, since some weed species have been reported to be hosts for SCN. The increase in the occurrence of resistance to herbicides complicates weed management and may further direct ecological–evolutionary (eco–evo) feedbacks in plant–pathogen complexes, including interactions between host plants and SCN. In this review, we summarize weed species reported to be hosts of SCN in the US and outline potential weed–SCN management interactions. Plants from 23 families have been reported to host SCN, with Fabaceae including most host species. Out of 116 weeds hosts, 14 species have known herbicide-resistant biotypes to 8 herbicide sites of action. Factors influencing the ability of weeds to host SCN are environmental and edaphic conditions, SCN initial inoculum, weed population levels, and variations in susceptibility of weed biotypes to SCN within a population. The association of SCN on weeds with relatively little fitness cost incurred by the latter may decrease the competitive ability of the crop and increase weed reproduction when SCN is present, feeding back into the probability of selecting for herbicide-resistant weed biotypes. Therefore, proper management of weed hosts of SCN should be a focus of integrated pest management (IPM) strategies to prevent further eco–evo feedbacks in the cropping system.

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Section 4. Pyrethroid and endosulfan resistance: selection and cross resistance studies

Bulletin of entomological research supplement series ◽

10.1017/s1367426900000102 ◽

1993 ◽

Vol 1 ◽

pp. 28-35 ◽

Cited By ~ 21

Author(s):

Neil W. Forrester ◽

Matthew Cahill ◽

Lisa J. Bird ◽

Jacquelyn K. Layland

Keyword(s):

Insecticide Resistance ◽

Lower Order ◽

Management Strategy ◽

Pyrethroid Resistance ◽

Resistance Management ◽

Resistance Mechanisms ◽

Cross Resistance ◽

Male And Female ◽

Insecticide Resistance Management ◽

Resistance Selection

SummaryResistance to endosulfan and pyrethroids in Helicoverpa armigera in Australia was shown to be due to multiple rather than cross resistance. The independence of the endosulfan and pyrethroid resistance mechanisms vindicates the sequential use of these two groups in Stages I and II of the insecticide resistance management strategy, respectively. Within the cyclodienes, greatest resistance occurred to dieldrin with lower order cross resistance to endosulfan and endrin. Male and female moths expressed cyclodiene resistance equally.

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A study on the ecology and economic impact of major invasive weed species of coconut homesteads of Nattika, India

Asia Pacific Journal of Environment Ecology and Sustainable Development ◽

10.3126/apjeesd.v1i1.9509 ◽

2014 ◽

Vol 1 (1) ◽

pp. 32-35

Author(s):

ES Abhilash ◽

Sheeja P Parayil ◽

Brijesh Sathian ◽

AR Raju ◽

NA Bilal ◽

...

Keyword(s):

Invasive Species ◽

Weed Management ◽

Management Strategy ◽

Alien Invasive Species ◽

Chromolaena Odorata ◽

Weed Species ◽

Invasive Weed ◽

Mikania Micrantha ◽

Medium Risk ◽

Genetic Aberration

Out of the 4 alien invasive species three are of high risk namely Mikania micrantha, Chromolaena odorata and Mimosa diplotricha. Lantana camara is found to be medium risk. The farmers spent a considerable amount of money nearly Rs 4800 per year for one acre land pertaining to mechanical weeding of invasive species. The herbicide is widely used by farmers to control the weeds are capable to cause various health problems including genetic aberration. So an effective and comprehensive weed management strategy have to be developed in the country to combat the threats of IAS in agriculture fields. DOI: http://dx.doi.org/10.3126/apjeesd.v1i1.9509Asia Pacific Journal of Environment Ecology and Sustainable Development 2013; 1: 32-35

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Widespread herbicide resistance in pigweed species in Ontario carrot production is due to multiple photosystem II mutations

Canadian Journal of Plant Science ◽

10.1139/cjps-2019-0114 ◽

2020 ◽

Vol 100 (1) ◽

pp. 56-67 ◽

Cited By ~ 1

Author(s):

Gareth Davis ◽

Jocelyne Letarte ◽

Christopher M. Grainger ◽

Istvan Rajcan ◽

François J. Tardif

Keyword(s):

Photosystem Ii ◽

Weed Management ◽

Continuous Selection ◽

Amaranthus Retroflexus ◽

Cross Resistance ◽

Single Mutation ◽

Weed Species ◽

Double Mutation ◽

First Report ◽

Selection Of

The apparent efficacy of linuron to control pigweeds (Amaranthus spp.) has declined in Ontario, Canada, in past decades, possibly due to resistance. Samples were collected in multiple fields across Ontario with reported linuron failure. These were characterized at the whole-plant and molecular levels. Screening with linuron revealed resistance in six out of nine green pigweed (Amaranthus powellii Wats.) populations and 36 out of 38 populations of redroot pigweed (Amaranthus retroflexus L.). Sequencing of the psbA gene showed resistant plants had mutations conferring resistance to photosystem II (PSII) inhibitors. The most commonly seen mutation was coding for a Val219Ile substitution, while other populations had Ala251Val or Phe274Val. Two populations were documented with a double mutation at Val219Ile and Phe274Val. All substitutions endowed plants with low to moderate resistance to linuron, with various levels of cross resistance to other PSII inhibitors. The double mutants were characterized by higher levels of resistance to linuron and diuron compared with each single substitution. The widespread failure of linuron to control pigweed species in many carrot fields in Ontario is due to the selection of PSII mutants. This is the first report of double mutation in psbA in any weed species and the first report of Ala251Val and Phe273Val in pigweed species. The presence of a double mutation is probably the result of continuous selection of plants already resistant due to a single mutation. Our results illustrate the need for diversified weed management strategies in crops where herbicide options are limited.

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Herbicide diagnostics reveal multiple patterns of synthetic auxin resistance in kochia (Bassia scoparia)

Weed Technology ◽

10.1017/wet.2021.69 ◽

2021 ◽

pp. 1-28

Author(s):

Charles M. Geddes ◽

Mallory L. Owen ◽

Teandra E. Ostendorf ◽

Julia Y. Leeson ◽

Shaun M. Sharpe ◽

...

Keyword(s):

Great Plains ◽

Dose Response ◽

Weed Management ◽

Acetolactate Synthase ◽

The United States ◽

Cross Resistance ◽

Visible Injury ◽

Synthetic Auxin ◽

Auxin Resistance ◽

Sites Of Action

Abstract Herbicide-resistant (HR) kochia is a growing problem in the Great Plains region of Canada and the United States (U.S.). Resistance to up to four herbicide sites of action, including photosystem II inhibitors, acetolactate synthase inhibitors, synthetic auxins, and the 5-enolpyruvylshikimate-3-phosphate synthase inhibitor glyphosate have been reported in many areas of this region. Despite being present in the U.S. since 1993/1994, auxinic-HR kochia is a recent and growing phenomenon in Canada. This study was designed to characterize (a) the level of resistance and (b) patterns of cross-resistance to dicamba and fluroxypyr in 12 putative auxinic-HR kochia populations from western Canada. The incidence of dicamba-resistant individuals ranged among populations from 0% to 85%, while fluroxypyr-resistant individuals ranged from 0% to 45%. In whole-plant dose-response bioassays, the populations exhibited up to 6.5-fold resistance to dicamba and up to 51.5-fold resistance to fluroxypyr based on visible injury 28 days after application. Based on plant survival estimates, the populations exhibited up to 3.7-fold resistance to dicamba and up to 72.5-fold resistance to fluroxypyr. Multiple patterns of synthetic auxin resistance were observed, where one population from Cypress County, Alberta was resistant to dicamba but not fluroxypyr, while another from Rocky View County, Alberta was resistant to fluroxypyr but not dicamba based on single-dose population screening and dose-response bioassays. These results suggest that multiple mechanisms may confer resistance to dicamba and/or fluroxypyr in Canadian kochia populations. Further research is warranted to determine these mechanisms. Farmers are urged to adopt proactive non-chemical weed management tools in an effort to preserve efficacy of the remaining herbicide options available for control of HR kochia.

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Resistance to Dodine in Populations of Venturia inaequalis in Quebec, Canada

Plant Health Progress ◽

10.1094/php-2010-0614-01-rs ◽

2010 ◽

Vol 11 (1) ◽

pp. 17 ◽

Cited By ~ 2

Author(s):

Odile Carisse ◽

Tristan Jobin

Keyword(s):

Management Strategy ◽

Venturia Inaequalis ◽

Apple Scab ◽

Resistance Management ◽

Cross Resistance ◽

Wild Type ◽

The Usa ◽

Control Failure ◽

Type Population ◽

Two Populations

Dodine was introduced in the USA and Canada in the early 1960s for the control of apple scab. Following control failure, growers stopped using dodine in the mid-1970s. Despite the curtailment of dodine use more than 30 years ago, persistent resistance to the fungicide was suspected in V. inaequalis populations. The dodine sensitivity was determined for two populations that were not exposed to dodine for at least 30 years – a wild type population (25 monoconidial isolates) and a population constructed with isolates collected in orchards managed for apple scab (156 isolates). The sensitivity to dodine was determined by monitoring growth of these isolates on agar Petri dishes amended with 0, 0.01, 0.1, 1.0, or 10.0 μg/ml of dodine. Sensitivity to fungicide was evaluated based on ED50 values. Both populations showed a lognormal distribution of ED50 values. The ED50 means were 0.525 μg/ml and 1.735 μg/ml for the wild type and managed orchards populations, respectively. In managed orchard, 31.4% of the isolates were resistant to dodine (ED50 > 1.0 μg/ml). Cross-resistance with myclobutanil and with kresoxim-methyl was tested and found not to be significant. The results of this study suggest that resistance to dodine is still present in the populations of V. inaequalis from Quebec and that reintroduction of dodine should only be done along with an appropriate resistance management strategy. Accepted for publication 27 April 2010. Published 14 June 2010.

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Carrots and Sticks: Incentives and Regulations for Herbicide Resistance Management and Changing Behavior

Weed Science ◽

10.1614/ws-d-15-00171.1 ◽

2016 ◽

Vol 64 (SP1) ◽

pp. 627-640 ◽

Cited By ~ 13

Author(s):

Michael Barrett ◽

John Soteres ◽

David Shaw

Keyword(s):

United States ◽

Herbicide Resistance ◽

Weed Management ◽

Cropping Systems ◽

Wide Spectrum ◽

Resistance Management ◽

Herbicide Tolerance ◽

The United States ◽

Weed Species ◽

Agricultural Community

Although the problem of herbicide resistance is not new, the widespread evolution of glyphosate resistance in weed species such as Palmer amaranth (Amaranthus palmeriS. Wats.), common waterhemp (Amaranthus rudisSauer), and kochia [Kochia scoparia(L.) Schrad.] raised awareness throughout the agricultural community of herbicide resistance as a problem. Glyphosate-resistant weeds resulted in the loss of a simple, single herbicide option to control a wide spectrum of weeds that gave efficacious and economical weed management in corn (Zea maysL.), soybean [Glycine max(L.) Merr.], and cotton (Gossypium hirsutumL.) crops engineered for tolerance to this herbicide and planted over widespread areas of the South and Midwest of the United States. Beyond these crops, glyphosate is used for vegetation management in other cropping systems and in noncrop areas across the United States, and resistance to this herbicide threatens its continued utility in all of these situations. This, combined with the development of multiple herbicide-resistant weeds and the lack of commercialization of herbicides with new mechanisms of action over the past years (Duke 2012), caused the weed science community to realize that stewardship of existing herbicide resources, extending their useful life as long as possible, is imperative. Further, while additional herbicide tolerance traits are being incorporated into crops, weed management in these crops will still be based upon using existing, old, herbicide chemistries.

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