Multiple origin of metallicolous populations of the pseudometallophyte Arabidopsis halleri (Brassicaceae) in central Europe: the cpDNA testimony

• Published in: Molecular ecology Vol. 14; no. 14; pp. 4403 - 4414
• Main Authors: Pauwels, M, Saumitou-Laprade, P, Holl, A.C, Petit, D, Bonnin, I
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.12.2005; Blackwell Publishing Ltd; Wiley
• Subjects: Adaptation, Physiological - genetics; Arabidopsis; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis halleri; Base Sequence; Botany; Brassicaceae; chloroplast DNA; chlorotypes; Cluster Analysis; cpDNA; DNA, Chloroplast - genetics; Europe; Genetic diversity; genetic polymorphism; Genetic Variation; Genetics; Genetics, Population; Geography; Haplotypes - genetics; heavy metal pollution; Heavy metals; Life Sciences; local adaptation; metal tolerance; Molecular biology; Molecular Sequence Data; PCR-RFLP; plant adaptation; Plant populations; polymerase chain reaction; Polymorphism, Restriction Fragment Length; Populations and Evolution; pseudometallophyte; Quantitative genetics; restriction fragment length polymorphism; Sequence Analysis, DNA; soil pollution; Zinc - metabolism; Europe; Central Europe
• ISSN: 0962-1083; 1365-294X
• DOI: 10.1111/j.1365-294X.2005.02739.x

The population structure of the pseudo‐metallophyte herb, Arabidopsis halleri, was studied using Polymerase Chain Reaction‐Restriction Fragment Length Polymorphism (PCR–RFLP) on chloroplast DNA (cpDNA). The history of metallicolous (M) populations showing increased zinc tolerance was investigated. Eight primer‐enzyme combinations out of 72 tested were applied to a total of 625 individuals from 28 widespread populations, 14 of them being M. Eleven distinct chlorotypes were found: five were common to nonmetallicolous (NM) and M populations, whereas six were only observed in one edaphic type (five in NM and one in M). No difference in chlorotype diversity between edaphic types was detected. Computed on the basis of chlorotype frequencies, the level of population differentiation was high but remained the same when taking into account levels of molecular divergence between chlorotypes. Isolation by distance was largely responsible for population differentiation. Geographically isolated groups of M populations were more genetically related to their closest NM populations than to each other. Our results suggest that M populations have been founded separately from distinct NM populations without suffering founding events and that the evolution towards increased tolerance observed in the distinct M population groups occurred independently.