Postglacial recolonization history of the European crabapple (Malus sylvestris Mill.), a wild contributor to the domesticated apple

A. Cornille (1) , T. Giraud (1) , C. Bellard (1) , A. Tellier (2) , Bruno Le Cam (3) , M. J. M. Smulders (4) , J. Kleinschmit (5) , I. Roldan-Ruiz (6) , P. Gladieux (1, 7)

1 ESE - Ecologie Systématique et Evolution
2 Sect Populat Genet, Ctr Life & Food Sci Weihenstephan
3 IRHS - Institut de Recherche en Horticulture et Semences
4 Plant Res Int
5 Dept Forest Genet Resources
6 ILVO - Research Institute for Agricultural, Fisheries and Food
7 Dept Plant & Microbial Biol

Understanding the way in which the climatic oscillations of the Quaternary Period have shaped the distribution and genetic structure of extant tree species provides insight into the processes driving species diversification, distribution and survival. Deciphering the genetic consequences of past climatic change is also critical for the conservation and sustainable management of forest and tree genetic resources, a timely endeavour as the Earth heads into a period of fast climate change. We used a combination of genetic data and ecological niche models to investigate the historical patterns of biogeographic range expansion of a wild fruit tree, the European crabapple (Malus sylvestris), a wild contributor to the domesticated apple. Both climatic predictions for the last glacial maximum and analyses of microsatellite variation indicated that M.sylvestris experienced range contraction and fragmentation. Bayesian clustering analyses revealed a clear pattern of genetic structure, with one genetic cluster spanning a large area in Western Europe and two other genetic clusters with a more limited distribution range in Eastern Europe, one around the Carpathian Mountains and the other restricted to the Balkan Peninsula. Approximate Bayesian computation appeared to be a powerful technique for inferring the history of these clusters, supporting a scenario of simultaneous differentiation of three separate glacial refugia. Admixture between these three populations was found in their suture zones. A weak isolation by distance pattern was detected within each population, indicating a high extent of historical gene flow for the European crabapple.

Mots clés: GLACIAL REFUGIA; CLIMATE-CHANGE; ICE-AGES; MICROSATELLITE MARKERS; COMPARATIVE PHYLOGEOGRAPHY; POPULATION-STRUCTURE; CHLOROPLAST DNA VARIATION; SPATIAL GENETIC-STRUCTURE; microsatellite; intraspecies diversification; fruit tree; ecological niche modelling; approximate Bayesian computation; SPECIES DISTRIBUTIONS; CONTRASTING PATTERNS

Domaines: Sciences du Vivant [q-bio]

A. Cornille, T. Giraud, C. Bellard, A. Tellier, Bruno Le Cam, et al.. Postglacial recolonization history of the European crabapple (Malus sylvestris Mill.), a wild contributor to the domesticated apple. Molecular Ecology, 2013, 22 (8), pp.2249 - 2263. ⟨10.1111/mec.12231⟩. ⟨hal-01209911⟩