Ecological Genetics

Marie
Marie
Sabine
Sabine
Rebecca
Rebecca

Group Interests

Wild plants encounter pathogens all the time. Nevertheless, devastating disease is rare in natural ecosystems, while it is a big problem in agriculture, where monoculture is commonly practiced. This phenomenon has often been attributed to the genetic heterogeneity in wild plant populations, which includes diversity in the ability to defend against different sets of pathogens. Heterogeneity is of particular interest when gene-for-gene resistance is at play, i.e. when specific variants of pathogen virulence factors are recognized by matching variants in the host resistance arsenal. 

A well-known study system for gene-for-gene resistance is Arabidopsis thaliana and its oomycete pathogen Hyaloperonospora arabidopsidis (Hpa); many host resistance genes, primarily of the nucleotide-binding leucine-rich-repeat (NLR) family, have been identified and studied at the molecular level. At the same time, sequencing efforts have described and characterized some of the exquisite sequence diversity of plant resistance genes. Both efforts employed a global collection of host plants, so we still know little about the spatial and temporal dynamics of ‘wild’ resistance genes and their variants right at the place where selection pressure is imposed by local pathogens and their virulence factors.

Adding to our global collection of Hpa isolates (pathodopsis.org) and Arabidopsis accessions (1001genomes.org), we have been isolating both partners at regional, local, and population scales both within our local Arabidopsis site network around Tübingen and at new additional places. With these resources, we identify resistance-conferring loci using classical genetics, study the geographical patterns of virulence and resistance, and investigate the sequences of disease resistance-conferring loci from the host plants we study. Our main areas of interest:

  • Spatial variation of disease resistance
  • Spatial and temporal persistence of resistance strategies
  • Evolutionary dynamics and heterogeneity of resistance-conferring loci