Background: Soil contamination with heavy metals is a widespread problem affecting natural, cultivated, urban and industrial sites. In recent years, phyto-extraction of metal contaminants using metal-accumulating and -tolerant plants – with the goal to rehabilitate anthropogenically polluted soils – has received considerable attention. The efficient application of such green technology requires a thorough understanding of the interplay between environment, genotype, and phenotype, which has rarely been achieved.
Aims: This project will build on a reciprocal transplant experiment established in 2015 in Southern Poland at field sites either not or strongly metal-contaminated (by mining and ore-refining activities during centuries) with the metal tolerant plant species Arabidopsis halleri. Using phenotypic characterization and whole genome re-sequencing at the population level, the principal objective is to link environmental, genotypic, and phenotypic features in this metal-affected biological system. The analyses will indicate genomic regions of interest for subsequent in-depth analysis at the individual level in a follow-up project.
Methods: In the framework of a collaboration project between WSL and the W. Szafer Institute of Botany from the Polish Academy of Sciences in Krakow, Poland, various growth, morphological and anatomical traits related to heavy-metal accumulation and tolerance in the experimental plants growing in both their original and transplantation habitat will be assessed. Population means in these variables will be associated to genomic variation (allele frequencies per population derived from pooled sequencing). Data will be analyzed in view of the two plant origins, i.e. contaminated versus non-contaminated environment. These environmental and genome-wide association analyses should pinpoint genomic regions and genes that are candidates for being involved in the adaptation of local populations to metal contamination.
Innovation and cross-disciplinarity: The interrelation between environment, genotype, and phenotype sets the frame for understanding local adaptation to environmental variation. However, very little empirical data on natural populations is hitherto available. Our METALink project will establish such correlations and thus provide the scientific basis with regard to deciphering metal-tolerance and accumulation mechanisms at the level of single genes or gene networks.
2016 - 2018