The aim of this study was to identify the group of highly polymorphic microsatellite markers for the identification of six pear cultivars (P. communis) and two individuals of wild pear (P. pyraster). From among 40 tested SSR markers, 19 were selected to profile genetic diversity in pear genotypes due to high polymorphisms. These markers showed high heterozygosity levels (0.5–1) and, on average, 6.4 alleles per marker were found. The set of microsatellite markers employed in this study demonstrated usefulness of microsatellite markers for the identification of pear genotypes. The examined wild forms were represented in this study by only two individuals of P. pyraster. It can be assumed that these forms were distinctly different from the cultivated pear cultivars.

In order to provide molecular characteristics of wild pear (P. pyraster) resources, six populations (192 accessions) from different regions of Poland were investigated with 17 SSR loci. Each of the SSR loci used was polymorphic, with a mean of 19.5 alleles per locus and a mean PIC of 0.806. Both the high heterozygosity (Ho = 0.751) and low Fis (0.007) indicated that the wild pear populations maintain a relatively high level of diversity, while the mean Findex of 0.039 and the number of migrants per generation (Nm = 6.996) revealed a high gene flow and weak inter-population differentiation. AMOVA analysis located polymorphisms mainly within populations (96%). Genetic relations between populations did not show correlations with geographical distances. The dispersal influence of gene flow could be the reason of the disrupted relationship within populations and the low interpopulation differentiation. We did not find any evidence to support the hypothesis about influence of interspecies hybridization with pear cultivars on the level of wild pear population diversity

The aim of this study was to investigate seed morphology and intra- and inter-population variation of seeds of Trollius europaeus L. and Trollius altissimus Crantz., two controversial species regarding their taxonomical position. We analyzed seed-coat microsculpture and some biometrical traits (length and width, width/length ratio, volume and projected perimeter). Seed sculpture did not differ between species, but seeds of T. altissimus were usually larger than seeds of T. europaeus. Although species differed significantly in seed morphology, it was possible to show the populations of both species that were similar regarding the analyzed seed traits. We noted a significant inter-population differentiation of seeds in both species with respect to seed-coat microornamentation and biometrical traits. We conclude that T. europaeus and T. altissimus are probably not two distinct species, but T. europaeus should be divided into two lower taxa in the rank of variety or subspecies.

Four taxa of Spiraea were selected for this study: S. × cinerea Zabel ‘Grefsheim’, S. nipponica Maxim. ‘Snowmound’, S. splendens É. N. Baumann ex K. Koch and S. × vanhouttei (Briot) Carrière growing for a minimum of 5 years along heavily trafficked traffic routes. This study included the genus Spiraea due to its popularity in horticultural practice (commercial availability, widespread in urban environments). In addition, the use of ornamental shrubs for phytoremediation in urban green spaces effectively combines the aesthetic needs of residents with those of caring for the urban environment. This study was conducted in Poznań (population 550,000, the fifth largest city in Poland). Soils and foliage were examined in spring and autumn. Soil pH and specific electrolytic conductivity (EC) were determined. The content of micronutrients (Cu, Fe, Mn, Ni, Zn) and toxic heavy metals (Cd, Cr, Pb) in soil dry matter and leaves was determined. The uptake capacity of bioavailable forms of heavy metals by Spiraea from the soil was analyzed by determining the bioconcentration factor (BCF). It was found that the studied taxa meet the basic requirements for plants used for soil phytoremediation processes, especially for chromium phytoextraction. The degree of salinity of the tested soils did not pose a threat to the shrubs growing there, and most of the sites, despite the alkaline reaction, are suitable for their cultivation. S. × cinerea and S. × vanhouttei have BCFs for lead <1. The remaining taxa are characterized by strong concentrations of all analyzed elements. A particularly high BCF, above 10, was recorded for chromium and high for manganese and nickel.