RESEARCH SUMMARY

The main objective of our research is to understand the genetic and molecular mechanisms involved in plant adaptation. We are dissecting the genetic variation in the model annual plant Arabidopsis thaliana in nature. Similar to many other plant species, individuals and populations of A. thaliana living in different geographical regions differ in many developmental traits that are presumed to reflect adaptations to different environments. To exploit this genetic variation for understanding plant adaptation, our group is currently focused on two specific objectives.

On the one hand, we are carrying out genetic analysis of the naturally-occurring variation for a key quantitative developmental trait such as the timing of flowering. We have developed several populations of recombinant inbred lines (RIL) and introgression lines (IL). We have analysed the relationship between the genetic basis of flowering initiation and the rate of vegetative growth in a new RIL population of 222 lines derived from the cross LerxFei-0. This population has been used for QTL (quantitative trait locus) mapping analysis, which indicated 10 genomic regions that show two distinct patterns of pleiotropic effects on both traits.

On the other hand, we have developed a collection of wild genotypes of A. thaliana from the Iberian peninsula, which serve as a permanent experimental population on which to carry out genetic and environmental association analyses. As a first step in exploiting this population, we characterized 182 Iberian genotypes for their flowering response to vernalisation and have sequenced several flowering genes. We found new wild allelic series of some flowering genes by association mapping. In addition, analysis of the geographic and climatic distribution of gene polymorphisms is enabling us to identify alleles that might be involved in climatic adaptation.