How do spatial heterogeneity and dispersal in weed population models affect predictions of herbicide resistance evolution?

2017 ◽  
Vol 362 ◽  
pp. 37-53 ◽  
Author(s):  
Gayle J. Somerville ◽  
Stephen B. Powles ◽  
Michael J. Walsh ◽  
Michael Renton
Keyword(s):  
Spatial Heterogeneity ◽  
Herbicide Resistance ◽  
Population Models ◽  
Weed Population ◽  
Resistance Evolution

scholarly journals STUDY OF SINGLE-SPECIES POPULATION MODELS

2020 ◽  
pp. 161-166
Author(s):  
Marthak Rutu
Keyword(s):  
Spatial Heterogeneity ◽  
Environmental Effects ◽  
Age Structure ◽  
Single Species ◽  
Research Paper ◽  
Population Models ◽  
Deterministic Models ◽  
One Dimensional ◽  
Species Population ◽  
Single Species Population

In this research paper one dimensional population models developed centuries ago shows that growth and/decay of single homogeneous populations But environmental effects spatial heterogeneity or age-structure deterministic models prevailing single species population models.

scholarly journals Tuning Spatial Profiles of Selection Pressure to Modulate the Evolution of Resistance

2017 ◽  
Author(s):  
Maxwell G. De Jong ◽  
Kevin B. Wood
Keyword(s):  
Drug Resistance ◽  
Spatial Heterogeneity ◽  
Selection Pressure ◽  
First Passage Time ◽  
Passage Time ◽  
Spatial Profile ◽  
Drug Dosing ◽  
Spatial Gradients ◽  
Resistance Evolution ◽  
Dosing Strategies

Spatial heterogeneity plays an important role in the evolution of drug resistance. While recent studies have indicated that spatial gradients of selection pressure can accelerate resistance evolution, much less is known about evolution in more complex spatial profiles. Here we use a stochastic toy model of drug resistance to investigate how different spatial profiles of selection pressure impact the time to fixation of a resistant allele. Using mean first passage time calculations, we show that spatial heterogeneity accelerates resistance evolution when the rate of spatial migration is sufficiently large relative to mutation but slows fixation for small migration rates. Interestingly, there exists an intermediate regime—characterized by comparable rates of migration and mutation—in which the rate of fixation can be either accelerated or decelerated depending on the spatial profile, even when spatially averaged selection pressure remains constant. Finally, we demonstrate that optimal tuning of the spatial profile can dramatically slow the spread and fixation of resistant subpopulations, even in the absence of a fitness cost for resistance. Our results may lay the groundwork for optimized, spatially-resolved drug dosing strategies for mitigating the effects of drug resistance.

On robust weed population models

Weed Research ◽  
1989 ◽  
Vol 29 (4) ◽  
pp. 229-238 ◽  
Author(s):  
A. M. MORTIMER ◽  
J. J. SUTTON ◽  
P. GOULD
Keyword(s):  
Population Models ◽  
Weed Population

The safener isoxadifen does not increase herbicide resistance evolution in recurrent selection with fenoxaprop

Plant Science ◽  
2021 ◽  
pp. 111097
Author(s):  
Carlos Alberto Gonsiorkiewicz Rigon ◽  
Luan Cutti ◽  
Paula Sinigaglia Angonese ◽  
Estefani Sulzbach ◽  
Catarine Markus ◽  
...  
Keyword(s):  
Herbicide Resistance ◽  
Recurrent Selection ◽  
Resistance Evolution

Selecting for Weed Resistance: Herbicide Rotation and Mixture

2009 ◽  
Vol 23 (3) ◽  
pp. 363-370 ◽  
Author(s):  
Hugh J. Beckie ◽  
Xavier Reboud
Keyword(s):  
Herbicide Resistance ◽  
Seed Bank ◽  
Rotation Frequency ◽  
Acetolactate Synthase ◽  
Resistance Evolution ◽  
Mixture Treatment ◽  
Field Pennycress ◽  
Inhibitor Resistance ◽  
Als Inhibitor ◽  
The Impact

Herbicide rotations and mixtures are widely recommended to manage herbicide resistance. However, little research has quantified how these practices actually affect the selection of herbicide resistance in weeds. A 4-yr experiment was conducted in western Canada from 2004 to 2007 to examine the impact of herbicide rotation and mixture in selecting for acetolactate synthase (ALS) inhibitor resistance in the annual broadleaf weed, field pennycress, co-occurring in wheat. Treatments consisted of the ALS-inhibitor herbicide, ethametsulfuron, applied in a mixture with bromoxynil/MCPA formulated herbicide (photosystem-II inhibitor/synthetic auxin), or in rotation with the non-ALS inhibitor at an ALS-inhibitor application frequency of 0, 25, 50, 75, and 100% (i.e., zero to four applications, respectively) over the 4-yr period. The field pennycress seed bank at the start of the experiment contained 5% ethametsulfuron-resistant seed. Although weed control was only marginally reduced, resistance frequency of progeny of survivors increased markedly after one ALS-inhibitor application. At the end of the experiment, the level of resistance in the seed bank was buffered by susceptible seed, increasing from 29% of recruited seedlings after one application to 85% after four applications of the ALS inhibitor. The level of resistance in the seed bank for the mixture treatment after 4 yr remained similar to that of the nontreated (weedy) control or 0% ALS-inhibitor rotation frequency treatment. The results of this study demonstrate how rapidly ALS-inhibitor resistance can evolve as a consequence of repeated application of herbicides with this site of action, and supports epidemiological information from farmer questionnaire surveys and modeling simulations that mixtures are more effective than rotations in mitigating resistance evolution through herbicide selection.

Rapid Evolution of Herbicide Resistance by Low Herbicide Dosages

Weed Science ◽  
2011 ◽  
Vol 59 (2) ◽  
pp. 210-217 ◽  
Author(s):  
Sudheesh Manalil ◽  
Roberto Busi ◽  
Michael Renton ◽  
Stephen B. Powles
Keyword(s):  
Herbicide Resistance ◽  
Rapid Evolution ◽  
Wheat Crop ◽  
Potted Plants ◽  
Resistance Evolution ◽  
Crop Field ◽  
Response Profiles ◽  
Rigid Ryegrass ◽  
The Impact ◽  
Resistance Traits

Herbicide rate cutting is an example of poor use of agrochemicals that can have potential adverse implications due to rapid herbicide resistance evolution. Recent laboratory-level studies have revealed that herbicides at lower-than-recommended rates can result in rapid herbicide resistance evolution in rigid ryegrass populations. However, crop-field-level studies have until now been lacking. In this study, we examined the impact of low rates of diclofop on the evolution of herbicide resistance in a herbicide-susceptible rigid ryegrass population grown either in a field wheat crop or in potted plants maintained in the field. Subsequent dose–response profiles indicated rapid evolution of diclofop resistance in the selected rigid ryegrass lines from both the crop-field and field pot studies. In addition, there was moderate level of resistance in the selected lines against other tested herbicides to which the population has never been exposed. This resistance evolution was possible because low rates of diclofop allowed substantial rigid ryegrass survivors due to the potential in this cross-pollinated species to accumulate all minor herbicide resistance traits present in the population. The practical lesson from this research is that herbicides should be used at the recommended rates that ensure high weed mortality to minimize the likelihood of minor herbicide resistance traits leading to rapid herbicide resistance evolution.

scholarly journals Defining Integrated Weed Management: A Novel Conceptual Framework for Models

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 747
Author(s):  
Jonathan Storkey ◽  
Joseph Helps ◽  
Richard Hull ◽  
Alice E. Milne ◽  
Helen Metcalfe
Keyword(s):  
Population Dynamics ◽  
Conceptual Framework ◽  
Herbicide Resistance ◽  
Weed Management ◽  
Integrated Weed Management ◽  
Management Options ◽  
Weed Population ◽  
Weed Population Dynamics ◽  
Population Dynamics Models ◽  
Dynamics Models

Weed population dynamics models are an important tool for predicting the outcome of alternative Integrated Weed Management (IWM) scenarios. The growing problem of herbicide resistance has increased the urgency for these tools in the design of sustainable IWM solutions. We developed a conceptual framework for defining IWM as a standardised input template to allow output from different models to be compared and to design IWM scenarios. The framework could also be used as a quantitative metric to determine whether more diverse systems are more sustainable and less vulnerable to herbicide resistance using empirical data. Using the logic of object-oriented programming, we defined four classes of weed management options based on the stage in the weed life cycle that they impact and processes that mediate their effects. Objects in the same class share a common set of properties that determine their behaviour in weed population dynamics models. Any weed control “event” in a system is associated with an object, meaning alternative management scenarios can be built by systematically adding events to a model either to compare existing systems or design novel approaches. Our framework is designed to be generic, allowing IWM systems from different cropping systems and countries to be compared.

Sign in / Sign up

Export Citation Format

Share Document