Agrochemical Resistance in Natural Populations: Prevalence, Molecular Mechanism and Evolution
Lead Research Organisation:
University of Oxford
Department Name: Interdisciplinary Bioscience DTP
Abstract
Resistance to pesticides is a global food security problem and a rising issue for the agrochemical sector, analogous to the global health concerns caused by widespread antibacterial resistance. A number of compound families, both wide spectrum pesticides and more targeted nematicides, are available for agricultural use to combat the damage caused by pests that results in about 15% of global crop loss annually. Most of these compounds were introduced decades ago and reports of resistance exist for each class, yet little is known about the molecular mechanism and evolutionary biology of resistance. Sometimes resistance takes decades to evolve, sometimes just a few years and some species evolve resistance more commonly than others.
We are evaluating the use of C. elegans as a model for understanding the mechanisms and evolution of pesticide resistance. Selection for resistance will act on natural variation in susceptibility in wild populations and such variation has been observed in C. elegans: for example the Hawaiian strain CB4856[1] is resistant to the nematicide avermectin through variation at the target protein. We have assessed natural variation in pesticide resistance by investigating the development of 25 highly divergent C. elegans wild isolates upon exposure to 29 bioactive insecticides, fungicides and nematicides and demonstrated both increased sensitivity as well as increased resistance to particular chemicals in different wild strains. We plan to identify the genetic basis of particular variation in resistance as well as to model the emergence of agrochemical resistance in an experimental evolution approach.
We are evaluating the use of C. elegans as a model for understanding the mechanisms and evolution of pesticide resistance. Selection for resistance will act on natural variation in susceptibility in wild populations and such variation has been observed in C. elegans: for example the Hawaiian strain CB4856[1] is resistant to the nematicide avermectin through variation at the target protein. We have assessed natural variation in pesticide resistance by investigating the development of 25 highly divergent C. elegans wild isolates upon exposure to 29 bioactive insecticides, fungicides and nematicides and demonstrated both increased sensitivity as well as increased resistance to particular chemicals in different wild strains. We plan to identify the genetic basis of particular variation in resistance as well as to model the emergence of agrochemical resistance in an experimental evolution approach.
People |
ORCID iD |
| Alison Woollard (Primary Supervisor) | |
| Liisa Parts (Student) |
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| BB/N503885/1 | 01/10/2015 | 30/09/2019 | |||
| 1649451 | Studentship | BB/N503885/1 | 01/10/2015 | 30/09/2019 | Liisa Parts |
| Description | This award funded research that investigated the use of a model organism C. elegans in agrochemical resistance mitigation. Using natural populations of C. elegans revealed the usefulness of the model in understanding natural variation in pesticide resistance in an attempt to quantify, prior to field studies, the prevalence of resistance alleles in a wild population that has not been exposed to a given pesticide. This is important as the it could potentially reveal chemicals with widespread resistance conferring natural variation before field studies and thus cutting compound research and development costs as a whole. Results of different experimental evolution studies (multi-generational adaptation and competition) revealed the evolutionary dynamics of the emergence of resistance to a particular pesticide. This, as a novel example, provides proof of similarities between resistance to antimicrobial or antimalarial agents and pesticidal compounds. The emergence of resistance in all cases is driven by the fitness cost conferred by resistance and a level of parallelism can be observed on the level of functional units (genes or pathways). |
| Exploitation Route | The findings of this project provide the first empirical results on pesticide resistance emergence and the wide range of factors that influence it. These results indicate that this model organism can be used to aid in the development of strategies to mitigate resistance emergence and thus aid in the establishment of better food security globally. |
| Sectors | Agriculture, Food and Drink |
| Description | School visit (Native Scientist Programme) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Schools |
| Results and Impact | As part of the Native Scientist programme I attended a Saturday school event at the London Estonian school and gave a number of short talks about my research to young children (ages 5-12). The primary focus was to introduce the concept of model organisms through showing the children how an animal like Caenorhabditis elegans that is in its looks very different humans or other animals can be used to understand various aspects of human or insect biology. The children found the videos I showed and C. elegans toy I brought along interesting and seemed engaged as they asked questions about the animals they had never seen before. The non-specialist parents with varying backgrounds and professions accompanying the children often found the concept interesting and new as well and it was a joy to see people departing with new knowledge regarding the use of laboratory nematodes. |
| Year(s) Of Engagement Activity | 2017 |
| URL | https://www.nativescientist.com/single-post/2017/05/26/Native-Scientist-speaks-Estonian-too |