Resources and potential for candidate-gene association studies in European black poplar for leaf rust resistance

High levels of variability for partial resistance to Melampsora larici-populina leaf rust in black poplar (Populus nigra L.) across Europe offers unique opportunity to identify favourable alleles through association studies. Nucleotide polymorphism (SNP and indels) within candidate genes has been explored in a discovery panel of 21 French P.nigra genotypes. Phenotyping for field and laboratory resistance components revealed significant diversity at both the intra and inter-metapopulation levels, with a suspected North vs. South geographical contrast