Chapuis, Marie Pierre

 Contact Details

 

Education and Professional Employment

2009 - current, Cirad Researcher, France (Honorary Research Affiliate of the School of Biological Sciences, Sydney, Australia)

2007 - 2009, Marie-Curie Outgoing International Fellow, CBGP, Montpellier and University of Sydney, Australia, with G.A. Sword and S. J. Simpson 

PhD. University of Montpellier, France 2006 (Supervisors: A. Estoup, Y. Michalakis & M. Lecoq)

MSc. University of Montpellier, France 2002 (Supervisor: A. Estoup)

 

Main Research Interests

My research is mainly focused on population evolution of insect species. I use molecular and evolutionary ecology to infer population histories and processes (e.g. routes of colonization, demographic quantities) and test for the roles of (a)biotic factors (e.g. landscape, microbial communities).

 

Ongoing Research Lines

Evolution of phase polyphenism in main locust species

At Cirad, we have a long history with locust species, such as the Desert locust, Schistocerca gregaria (picture: Antoine Foucart, Augrabies Falls, South-Africa) or the migratory locust, Locusta migratoria. These crop pests are subject to huge and unpredictable increases in population density, associated with a switch from the shy and cryptic to the highly active and aggregative behavior (the so-called phase polyphenism, an extreme density-dependent phenotypic plasticity). We are interested in documenting reaction norms of polyphenic traits (e.g. behavior, growth, morphology, reproduction), in exploring genetic parameters (e.g. heritability of traits) and mechanisms (e.g. heat shock proteins) as well as evolutionary hypotheses (e.g. resource use optimization) involved in phenotypic plasticity, and in identifying the environmental conditions leading to the evolution of phase polyphenism and population outbreaks. For further details, see the dedicated webpage.

Main collaborators: Hélène Jourdan, Yannis Michalakis, Benjamin Pélissié, Cyril Piou, Camille Vernier.

Main publications : 4, 8, 9, 11, 14, 27, 32, 36, 38, 40, 41.  

 

Characterization of the diversity of insect species associated with field crops 

This initiative aims at contributing to the international efforts to develop species identification tools, primarily in the Orthoptera. Such efforts are often applied at a deep taxonomic level by using high-throughput sequencing of multiple DNA markers. At this level, we sequence amplicons (e.g., mitochondrial barcode, nuclear fragments) from ancient DNA from Western-African specimens of the diverse Acrididae family from our collection. Identification can otherwise be problematic at a recent taxonomic level, which requires integrative revisions based on morphological and molecular data. At this level, we focus on two Orthopteran case studies: we use the RAD-Seq technique, geometrical morphometry and the study of acoustic communication to explore species limits within the Calliptamus genus, and we combine microsatellite genotyping, mitochondrial barcoding, and morphological and ecological data to resolve the enigmatic genetic isolation of the ‘Palavas grasshopper', a giant form of the migratory locust. Finally, we build on the RAD-Capture method from Ali et al. (2016) to target several thousand SNP markers, selected for their quality and high level of polymorphism to describe the worldwide structure of populations from the Bactrocera dorsalis complex, and develop a molecular tool for rapid identification of the geographical origin and specific status of quarantine fruit flies caught in monitoring networks from EU phytosanitary services.

Main collaborators: Emeline Charbonnel, Armelle Coeur d'Acier, Emmanuelle Jousselin, David Ouvrard.
 
 
Landscape genomics for agro-ecology
 
Crop pests are a major constraint to ecological intensification of agricultural production systems. We develop and extend a landscape genomics approach to address pest dispersal in relation to their environment as a prerequisite to improve pest management strategies. Our main case study is the Oriental fruit fly, Bactrocera dorsalis, an invasive key pest of mango and other fruits, for which we implement an intensive demo-genetic monitoring in West Africa. We assess and/or develop (i) high-throughput sequencing techniques for generating SNPs on a large number of samples at a reasonable cost, (ii) statistical methods to characterize the spatiotemporal relationships between pest abundance, active short-distance dispersal, passive long-distance dispersal, and the environmental matrix, and (iii) inferential methods to quantify the spatiotemporal variation of demographic parameters taking into account the landscape. French speakers will find more details on this project in an article published in the magazine "Passion Entomologie".
 
Main collaborators: Karine Berthier, Thierry Brévault, Cécile Caumette, Raphaël Leblois, Sylvain Piry.
 
Main publications (so far): 28, 33.
 

   
Plant-insect-bacteria interactions  

Communities of microorganisms (microbiota) have an intimate, often mutualistic, but also complex relationship with their host and its environment. As a first step toward considering the microbial compartment for solving key questions in plant health, we characterize microbiota composition variation in phytophagous insects according to host plants (e.g. fruit species in fruit flies or wheat genotypes in the migratory locust). We also explore immune (e.g. parasitism), behavioral (e.g. gregarious phase) or genetic (e.g. evolutionary history) factors.

Main collaborators: Simon Fellous, Isabelle Florent, Marion Javal, Nicolas Rode.

Main publications (so far): 30, 37, 39, 42.