Evaluation of genetic diversity of Himalayan balsam (Impatiens glandulifera Royle) populations using microsatellites

Himalayan balsam (Impatiens glandulifera Royle) belongs to invasive alien species of European Union concern. Acquisition of the new molecular data from a geographical point of view might be valuable getting ideas about the nowadays invasion steps of I. glandulifera to more northern and eastern parts of the Europe, the source population(s) in the local scale as well as for elucidation of the patterns of the spread of alien species in Lithuania. In the period of 2010-2019, 95 sites of I. glandulifera were recorded in Lithuania. The present study was aimed at evaluation of genetic diversity at microsatellite loci of Lithuanian populations of I. glandulifera. For molecular analysis employing 9 microsatellite (simple sequence repeats, SSR) markers, a total of 20 Lithuanian populations of I. glandulifera (15 individuals in each) were used. Allelic richness (A(R)) ranged from 1.1 to 1.39 per population, and the expected heterozygosity (HE) ranged from 0.10 to 0.39 per one. No significant correlation (according to Mantel test) between the geographic distances and genetic differentiation was determined between the Lithuanian populations of I. glandulifera. AMOVA showed that variability within the populations (56.2%) was higher than that among the populations (43.7%). According to the principal coordinate analysis (PCoA), three principal axes explained 60% of the total genetic variation of populations. Significant results were obtained when the populations were grouped according to the five geographical areas of Lithuania: variation among the groups comprised 5.73% of the total variation. Bayesian clustering analysis indicated the highest & UDelta;K values at K = 12, and the next highest value was K = 3. It may indicate the multiple introductions of I. glandulifera to Lithuania.