Chemical Control of Glyphosate-Resistant Goosegrass

ABSTRACT: The use of mixtures and rotation of herbicide modes of action are essential for herbicide resistance management. The purpose of this research was to evaluate different pre- and post-emergence herbicides to control goosegrass in soybean and corn. Four greenhouse experiments were conducted, one in pre-emergence and the three others in post-emergence. In pre-emergence, the number of emerged plants and the control percentage at 20, 35 and 50 days after application were evaluated. In post-emergence, the control percentage was evaluated at 14 and 28 days after application on plants with one tiller and four tillers. The use of residual herbicides to control glyphosate-resistant goosegrass is a very important tool for its effective management. The application stage is also crucial for post-emergence efficacy. Paraquat and [paraquat + diuron] are effective in controlling this species. The application of ACCase inhibiting herbicides alone seems to be more effective than their associations with glyphosate, especially in plants with four tillers. HPPD inhibiting herbicides have high synergism with atrazine and not with glyphosate.

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Managing Insecticide and Miticide Resistance in Florida Landscapes

EDIS ◽

10.32473/edis-in714-2018 ◽

2018 ◽

Vol 2018 (4) ◽

Author(s):

Nicole Benda ◽

Adam G. Dale

Keyword(s):

Insecticide Resistance ◽

Chemical Control ◽

Ornamental Plants ◽

Resistance Management ◽

Fact Sheet ◽

Insecticide Resistance Management ◽

Modes Of Action ◽

The World

Resistance to insecticide or miticide is a worry for landscape managers. Around the world, chinch bugs, leafminers, and other insect and mite pests have become resistant to dozens of insecticides, but with diligent insecticide resistance management, we can still maintain long-term effective chemical control. With few new modes of action coming onto the market, landscape managers need to be good stewards of existing products. Ultimately, resistance management means reducing exposure of pests to any one pesticide. Fortunately, there are many ways to prevent resistance and still control pests of ornamental plants and lawns, and this 6-page fact sheet written by Nicole Benda and Adam Dale and published by the UF/IFAS Entomology and Nematology Department explains how. http://edis.ifas.ufl.edu/in714

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Fitness of Herbicide-Resistant Weeds: Current Knowledge and Implications for Management

Plants ◽

10.3390/plants8110469 ◽

2019 ◽

Vol 8 (11) ◽

pp. 469 ◽

Cited By ~ 5

Author(s):

Vila-Aiub

Keyword(s):

Life History ◽

Herbicide Resistance ◽

Management Practices ◽

Current Knowledge ◽

Resistance Management ◽

Fitness Cost ◽

Plant Fitness ◽

Resistance Mutations ◽

Fitness Costs ◽

Wide Range

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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Seed production of barnyardgrass (Echinochloa crus-galli) in response to time of emergence in cotton and rice

The Journal of Agricultural Science ◽

10.1017/s0021859611000876 ◽

2011 ◽

Vol 150 (6) ◽

pp. 717-724 ◽

Cited By ~ 16

Author(s):

M. V. BAGAVATHIANNAN ◽

J. K. NORSWORTHY ◽

K. L. SMITH ◽

P. NEVE

Keyword(s):

United States ◽

Seed Production ◽

Herbicide Resistance ◽

Crop Production ◽

Integrated Management ◽

Resistance Management ◽

Simulation Models ◽

Effective Resistance ◽

Southern United States

SUMMARYThe 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 response to time of emergence was investigated in cotton and rice, respectively, in Fayetteville and Rohwer, Arkansas, over a 2-year period (2008–09). Barnyardgrass seed production was greater when seedlings emerged with the crop, but some seed production was observed even if seedlings emerged several weeks after crop emergence. Moreover, barnyardgrass seed production was highly variable across environments. When emerging with the crop (0 weeks after crop emergence (WAE)), barnyardgrass producedc. 35 500 and 16 500 seeds/plant in cotton, andc. 39 000 and 2900 seeds/plant in rice, in 2008 and 2009, respectively. Seed production was observed when seedlings emerged up to 5 WAE (2008) or 7 WAE (2009) in cotton and up to 5 WAE (2008, 2009) in rice; corresponding seed production wasc. 2500 and 1500 seeds/plant in cotton, andc. 14 700 and 110 seeds/plant in rice, in 2008 and 2009, respectively. The results suggest that cultural approaches that delay the emergence of barnyardgrass or approaches that make the associated crop more competitive will be useful in integrated management programmes. In the context of herbicide resistance management, it may be valuable to prevent seed return to the seedbank, irrespective of cohorts. The findings are vital for parameterizing herbicide resistance simulation models for barnyardgrass.

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Managing Herbicide Resistance: Listening to the Perspectives of Practitioners. Procedures for Conducting Listening Sessions and an Evaluation of the Process

Weed Technology ◽

10.1017/wet.2018.53 ◽

2018 ◽

Vol 32 (4) ◽

pp. 489-497 ◽

Cited By ~ 2

Author(s):

Jill Schroeder ◽

Michael Barrett ◽

David R. Shaw ◽

Amy B. Asmus ◽

Harold Coble ◽

...

Keyword(s):

Small Group ◽

Herbicide Resistance ◽

Planning Process ◽

Resistance Management ◽

Time Of Day ◽

Full Group ◽

Group Discussions ◽

Small Group Discussions ◽

The Subject ◽

Selection Of

AbstractSeven half-day regional listening sessions were held between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide-resistance management. The objective of the listening sessions was to connect with stakeholders and hear their challenges and recommendations for addressing herbicide resistance. The coordinating team hired Strategic Conservation Solutions, LLC, to facilitate all the sessions. They and the coordinating team used in-person meetings, teleconferences, and email to communicate and coordinate the activities leading up to each regional listening session. The agenda was the same across all sessions and included small-group discussions followed by reporting to the full group for discussion. The planning process was the same across all the sessions, although the selection of venue, time of day, and stakeholder participants differed to accommodate the differences among regions. The listening-session format required a great deal of work and flexibility on the part of the coordinating team and regional coordinators. Overall, the participant evaluations from the sessions were positive, with participants expressing appreciation that they were asked for their thoughts on the subject of herbicide resistance. This paper details the methods and processes used to conduct these regional listening sessions and provides an assessment of the strengths and limitations of those processes.

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Fungicide resistance characterised across seven chemical classes in a Botrytis cinerea population isolated from Australian vineyards

10.1101/2021.03.31.437981 ◽

2021 ◽

Author(s):

Lincoln A. Harper ◽

Scott Paton ◽

Barbara Hall ◽

Suzanne McKay ◽

Richard P. Oliver ◽

...

Keyword(s):

Adverse Effect ◽

Botrytis Cinerea ◽

Fungicide Resistance ◽

Chemical Control ◽

Management Strategies ◽

Resistance Management ◽

Gray Mold ◽

Chemical Groups ◽

Important Disease ◽

Selection Of

AbstractGray mold, caused by Botrytis cinerea, is an economically important disease of grapes in Australia and across grape growing regions worldwide. Control of this disease relies heavily on canopy management and the application of single site fungicides. Fungicide application can lead to the selection of fungicide resistant B. cinerea populations, which has an adverse effect on the chemical control of the disease. Characterising the distribution and severity of resistant B. cinerea populations is needed to inform resistance management strategies. In this study, 725 isolates were sampled from 75 Australian vineyards during 2013 – 2016 and were screened against seven fungicides with different MOAs. The resistance frequencies for azoxystrobin, boscalid, fenhexamid, fludioxonil, iprodione, pyrimethanil and tebuconazole were 5, 2.8, 2.1, 6.2, 11.6, 7.7 and 2.9% respectively. Nearly half of the resistant isolates (43.7%) were resistant to more than one of the fungicides tested. The frequency of vineyards with at least one isolate simultaneously resistant to 1, 2, 3, 4 or 5 fungicides was 19.5, 7.8, 6.5, 10.4 and 2.6%.Resistance was associated with previously published genotypes in CytB (G143A), SdhB (H272R/Y), Erg27 (F412S), Mrr1 (D354Y), Os1 (I365S, N373S + Q369P, I365S + D757N) and Pos5 (P319A, L412F). Expression analysis was used to characterise fludioxonil resistant isolates exhibiting overexpression (6.3 - 9.6-fold) of the ABC transporter encoded by AtrB (MDR1 phenotype). Novel genotypes were also described in Mrr1 (S611N, D616G) and Cyp51 (P357S). Resistance frequencies were lower when compared to most previously published surveys of both grape and non-grape B. cinerea resistance. Nonetheless, continued monitoring of critical chemical groups used in Australian vineyards is recommended.

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Development of sunflower hybrids tolerant to tribenuron methyl

Genetika ◽

10.2298/gensr1101175j ◽

2011 ◽

Vol 43 (1) ◽

pp. 175-182 ◽

Cited By ~ 7

Author(s):

Sinisa Jocic ◽

Goran Malidza ◽

Sandra Cvejic ◽

Nada Hladni ◽

Vladimir Miklic ◽

...

Keyword(s):

Helianthus Annuus ◽

Herbicide Resistance ◽

Chemical Control ◽

Resistance Breeding ◽

Inbred Lines ◽

Cirsium Arvense ◽

Helianthus Annuus L ◽

Exact Number ◽

Number Of Genes ◽

Tribenuron Methyl

Discovery of tribenuron-methyl resistant wild Helianthus annuus L. population (ANN-KAN) created an opportunity for expansion of sunflower herbicide resistance breeding program. The aim of this study was development of sunflower hybrids resistant to tribenuron-methyl. Creation of tribenuron-methyl resistant hybrids would enable the use of a wider palette of herbicides for sunflower, more efficient chemical control of Cirsium arvense and more economically profitable post-emergence control of some annual broad-leaves weeds in sunflower. Original populations SURES-1 and SURES-2 are homozygous for resistance to tribenuron-methyl. F1 generations produced from the crossings are completely resistant to tribenuron-methyl, pointing out to dominant way of inheritance of this trait. Studies on the exact number of genes controlling the resistance are in progress. Tribenuron-methyl resistance was transferred from original populations into a number of female and male inbred lines of cultivated sunflower. These inbred lines could enable creation of a number of hybrids resistant to tribenuron-methyl. Hybrids SUMO-1-PR, SUMO-2- OR and SUMO-3 are resistant to doubled application dose of tribenuron-methyl. Agronomical characteristics of these hybrids are on the level with the leading conventional sunflower hybrids.

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Mixtures as a Fungicide Resistance Management Tactic

Phytopathology ◽

10.1094/phyto-04-14-0121-rvw ◽

2014 ◽

Vol 104 (12) ◽

pp. 1264-1273 ◽

Cited By ~ 35

Author(s):

Frank van den Bosch ◽

Neil Paveley ◽

Femke van den Berg ◽

Peter Hobbelen ◽

Richard Oliver

Keyword(s):

At Risk ◽

Disease Control ◽

Fungicide Resistance ◽

Management Strategies ◽

Resistance Management ◽

Relative Effect ◽

Resistance Evolution ◽

Modes Of Action ◽

Selection For ◽

Effective Life

We have reviewed the experimental and modeling evidence on the use of mixtures of fungicides of differing modes of action as a resistance management tactic. The evidence supports the following conclusions. 1. Adding a mixing partner to a fungicide that is at-risk of resistance (without lowering the dose of the at-risk fungicide) reduces the rate of selection for fungicide resistance. This holds for the use of mixing partner fungicides that have either multi-site or single-site modes of action. The resulting predicted increase in the effective life of the at-risk fungicide can be large enough to be of practical relevance. The more effective the mixing partner (due to inherent activity and/or dose), the larger the reduction in selection and the larger the increase in effective life of the at-risk fungicide. 2. Adding a mixing partner while lowering the dose of the at-risk fungicide reduces the selection for fungicide resistance, without compromising effective disease control. The very few studies existing suggest that the reduction in selection is more sensitive to lowering the dose of the at-risk fungicide than to increasing the dose of the mixing partner. 3. Although there are very few studies, the existing evidence suggests that mixing two at-risk fungicides is also a useful resistance management tactic. The aspects that have received too little attention to draw generic conclusions about the effectiveness of fungicide mixtures as resistance management strategies are as follows: (i) the relative effect of the dose of the two mixing partners on selection for fungicide resistance, (ii) the effect of mixing on the effective life of a fungicide (the time from introduction of the fungicide mode of action to the time point where the fungicide can no longer maintain effective disease control), (iii) polygenically determined resistance, (iv) mixtures of two at-risk fungicides, (v) the emergence phase of resistance evolution and the effects of mixtures during this phase, and (vi) monocyclic diseases and nonfoliar diseases. The lack of studies on these aspects of mixture use of fungicides should be a warning against overinterpreting the findings in this review.

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Use of crop protection chemicals for integrated pest control

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1981.0127 ◽

1981 ◽

Vol 295 (1076) ◽

pp. 125-141 ◽

Cited By ~ 10

Keyword(s):

Chemical Control ◽

Crop Production ◽

Crop Protection ◽

Resistance Management ◽

Control Programme ◽

Pyrethroid Insecticides ◽

Application Techniques ◽

Integrated Pest Control ◽

Arthropod Pest ◽

Pest Management Systems

Examples of and methods for achieving the selective use of pesticides in control of pests while conserving important beneficial natural enemies are discussed relative to the development of integrated pest management systems for apples in the U.S.A. Included are examples of physiologically selective acaricides, ecological selectivity conferred by application techniques and selectivity due to the development of resistant beneficial insects. A definition and examples of ideal selectivity of pesticides for this crop production system are discussed. Lastly, an approach to resistance management in an entire apple arthropod pest - natural enemy complex is discussed in relation to a long-used chemical control system (organophosphate pesticides) compared with a new chemical control programme based on pyrethroid insecticides.

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