Understanding the recent colonization history of a plant pathogenic fungus using population genetic tools and Approximate Bayesian Computation

Barrès Benoit, Carlier Jean, Seguin Marc, Fenouillet Catherine, Cilas Christian, Ravigné Virginie. 2012. Understanding the recent colonization history of a plant pathogenic fungus using population genetic tools and Approximate Bayesian Computation. Heredity, 109 : 269-279.

https://doi.org/10.1038/hdy.2012.37

Article de revue ; Article de revue à facteur d'impact

Version publiée - Anglais
Accès réservé aux personnels Cirad
Utilisation soumise à autorisation de l'auteur ou du Cirad.
document_566132.pdf
Télécharger (1MB)

Quartile : Q1, Sujet : ECOLOGY / Quartile : Q1, Sujet : GENETICS & HEREDITY / Quartile : Q2, Sujet : EVOLUTIONARY BIOLOGY

Résumé : Understanding the processes by which new diseases are introduced in previously healthy areas is of major interest in elaborating prevention and management policies, as well as in understanding the dynamics of pathogen diversity at large spatial scale. In this study, we aimed to decipher the dispersal processes that have led to the emergence of the plant pathogenic fungus Microcyclus ulei, which is responsible for the South American Leaf Blight (SALB). This fungus has devastated rubber tree plantations across Latin America since the beginning of the twentieth century. As only imprecise historical information is available, the study of population evolutionary history based on population genetics appeared most appropriate. The distribution of genetic diversity in a continental sampling of four countries (Brazil, Ecuador, Guatemala and French Guiana) was studied using a set of 16 microsatellite markers developed specifically for this purpose. A very strong genetic structure was found (Fst=0.70), demonstrating that there has been no regular gene flow between Latin American M. ulei populations. Strong bottlenecks probably occurred at the foundation of each population. The most likely scenario of colonization identified by the Approximate Bayesian Computation (ABC) method implemented in DIYABC suggested two independent sources from the Amazonian endemic area. The Brazilian, Ecuadorian and Guatemalan populations might stem from serial introductions through human-mediated movement of infected plant material from an unsampled source population, whereas the French Guiana population seems to have arisen from an independent colonization event through spore dispersal.

Mots-clés Agrovoc : Microcyclus ulei, Hevea brasiliensis, marqueur génétique, histoire, dynamique des populations, transmission des maladies, modèle mathématique, microsatellite, épidémiologie, génie génétique

Mots-clés géographiques Agrovoc : Équateur, Brésil, Guyane française, Guatemala, France

Mots-clés complémentaires : Émergence

Classification Agris : H20 - Maladies des plantes
U10 - Informatique, mathématiques et statistiques

Champ stratégique Cirad : Axe 1 (2005-2013) - Intensification écologique

Auteurs et affiliations