Development and characterization of microsatellite markers in black poplar (Populus nigra L.)

Using an enrichment procedure, we have cloned and sequenced microsatellite loci from black poplar (Populus nigra L.) and developed primers for sequence-tagged microsatellite (STMS) analysis. Twelve primer pairs for dinucleotide repeats produced fragments of sufficient quality which were polymorphic in P. nigra. Some of them also showed amplification in other Populus species (P. deltoides, P. tricocarpa, P. tremula, P. tremuloides, P. candicans, and/or P. lasiocarpa). The best nine and (GT) (GA) microsatellite markers were tested on a set of 23 P. nigra genotypes from all over Europe. The microsatellites were highly polymorphic, with 10-19 different alleles per microsatellite locus among these 23 genotypes. WPMS08 sometimes amplified three fragments. Using the other eight marker loci, the level of heterozygosity among the plants was on average 0.71 (range 0.25-1.00). The microsatellite markers developed will be useful for screening the genetic diversity in natural populations and in gene bank collections.