Development of 5S rDNA-Based Molecular Markers for the Identification of Populus deltoides Bartr. ex Marshall, Populus nigra L., and Their Hybrids

Abstract

Populus L. is a tree genus that includes species with a high ability for interspecies hybridization. This process takes place in nature, and is used in poplar breeding. As а result, species identification in poplar populations and plantations is very difficult. In this study, a molecular marker system was developed for the identification of the most significant poplar species (P. nigra L. and P. deltoids Bartr. ex Marshall). The basis of the system is a polymorphism in non-transcribed spacers (NTSs) of 5S rDNA. The species-specific molecular markers were tested on a number of species and hybrids of poplars. It was shown that the marker system is a powerful tool for species identification, hybrid analysis, parent identification, and poplar breeding.