Volume 46 (2017): Issue 1 (June 2017)

The rpo genes are characterized by rapidly-evolving sequences. They encode subunits of plastid-encoded (PEP) polymerase (rpoA, rpoB, rpoC1 and rpoC2). This polymerase is one of the most important enzymes in the chloroplasts. The primary aim of the research was to study the rate of molecular evolution in the rpo genes and to estimate these genes as phylogenetic markers based on the example of the genus Erica (Ericaceae). The tested rpo genes demonstrated similarities on multiple levels, for example: phylogenetic informativeness, variation level, intragenic mutation rates and the effect of intragenic mutations on the properties of encoded peptides. This study did not confirm that the analyzed rpo genes are reliable markers and may be helpful in understanding phylogenetic relationships between species that belong to the same genus. The rpoC2 gene was found to be a most useful phylogenetic marker in the Erica genus, while rpoC1 was found to be the least promising gene.

The population structure of Carex dioica – a rare boggy species in Ukraine – has been studied for the first time. As a result, five types of spatial arrangement of C. dioica individuals, depending on their reproduction and living conditions, were established: scattered-diffuse, densely-diffuse, group, spotted and mosaic. Intensive vegetative propagation (often in the absence of seed reproduction) of individuals contributes to the group and spotted spatial structure of population. For low intensity of seed and vegetative reproduction, the arrangement of generative individuals turned out to be scattered-diffuse. Effective generative reproduction of a population was accompanied by a densely-diffuse distribution of individuals, and a combined type of reproduction (effective generative and vegetative) under favourable growth conditions contributes to its mosaic spatial structure.

Regardless of the growth conditions, all C. dioica populations were characterised by a left-hand age spectrum which was the result of an effective vegetative renovation of individuals and a stress-tolerant type of strategy of this species.

Under optimal growth conditions, the C. dioica populations were characterised by the prevalance of females compared to male ones (2:1), and under stress – a radical change in their sex ratio was observed towards a complete dominance of one of the genders. It was found that 50% of the studied C. dioica populations appeared to be thriving. Regardless of the vitality type of the population, the female individuals of this species, compared to male ones, realised their growth potential much better and, therefore, made a greater contribution to population vitality.

The list of alien vascular plant species only temporarily occurring in Wielkopolska refers to the previously published list of native and permanently established plants. Together, these two lists document the vascular flora of this region at the beginning of the 21st century. The current list, like the previous one, is a result of critical analysis of both contemporary and historical data, collected since the beginning of the 19th century. All information accessible in herbarium collections, publications and unpublished materials was used. A critical analysis was conducted at the taxonomic, nomenclatural, chorological and habitat levels, based on the verification of negative information not supported by sufficient arguments. The list is presented in an alphabetical order. Information on each species includes: family affinity, life form, geographic and historic status. In cases particularly disputable, the standard characteristic of a species was supplemented with an additional commentary.