Jacek Urbaniak

Genetic and morphological data fail to differentiate Chara intermedia from C. baltica, or C. polyacantha and C. rudis from C. hispida

Genetic variation of five species belonging to the section Hartmania – Chara baltica, C. intermedia, C. hispida, C. polyacantha and C. rudis – was investigated using Amplified Fragment Length Polymorphism (AFLP) techniques. Chara intermedia can be distinguished from the others by the presence or absence of numerous morphological characters. However, probably because of the high variability of the morphological features and common occurrence of apparently transitional forms, more than 80 specimens of the five species were collected and analysed. The specimens were collected from a total of 24 sites, including freshwater localities and sites in the Baltic Sea, initially classified into the five species based on morphological features, and then analysed using AFLP; as an outgroup we used C. globularis. The specimens formed two groups, the first group comprising C. intermedia and C. baltica, the second C. hispida, C. rudis and C. polyacantha. No consistent genetic differences were found between species within each of the two groups. Transitional forms of C. hispida/C. rudis were placed in a clade between individuals of C. hispida and C. rudis. Local populations of some charophytes differ morphologically from one another, possibly as a result of local adaptation.

Oospore variation in Nitella gracilis and Nitella mucronata (Charales, Charophyceae) from Poland

The determination of the members of Charales (Charophyceae) is not easy. The main reason of this is a wide range of variation in vegetative characters within most of the species. Many features such as the extent of branchlet cortication, the degree of incrustation, length and number of bract cells, spine cells, stipulodes, diameter of the main axis and oospore size and color do not have universal taxonomic significance. In similar, many Nitella species characters such as: general habitus, branchlets and presence of the top segment (mucro), are helpful in determination, however they are often not developed. In this case, the features of oospore wall ornamentation revealed by light and scanning microscopy can be important taxonomic characters of the Charales. The present study shows interspecific variations of the oospore in two Nitella species from Poland which can be helpful in correct determination of both species. Some of the oospore features like number of striae and fossa width can not be used, as they appeared statistically unimportant, and cannot be used in distinguishing between both species. The presented results are the first detailed report of oospore wall ornamentation pattern from Poland for the species studied. Oospore features are presented in detail on the background of some additional tips and among them particularly: length and width of the oospore, ISI idex, width of fossa, width of striae and number of striae.

Oospore Wall Ornamentation in the Genus Tolypella (Charales, Charophyceae).

The ultrastructural features of oospore wall ornamentation in the genus Tolypella were examined using scanning electron microscopy (SEM). The taxonomic relationships among several species were discussed on the basis of oospore ultrastructure and measurements. In the case of T. glomerata and T. nidifica, our results support the status of separate species. Close relationships and transitional forms may exist between T. nidifica and T. normaniana, and not only in oospore wall ornamentation. Oospores of T. hispanica exhibited the same distinct type of reticulate oospore wall as previously reported, but our results do not support the recognition of T. hispanica as a separate species. Ultrastructure of the oospore walls of T. prolifera and T. intricata was almost identical, suggesting that these species are closely related. We therefore reject previous suggestions that morphological characteristics of oospores as observed in SEM are sufficient for identification of individual species. Although significant differences were found among oospores in individual species of Tolypella, large variation among populations, and among individuals belonging to the same population, caused substantial overlap among species.

Molecular, morphological and ultrastructural characteristics of Prasiola crispa (Lightfoot) Kützing (Chlorophyta) from Spitsbergen (Arctic)

It is commonly known that seabirds, along with cyanobacteria, play a key role in the enrichment of nutrient-poor polar terrestrial ecosystems. In habitats particularly enriched with nitrogen and phosphate ions, ornithogenic vegetation with Prasiola crispa and unique species composition develops. However, no studies have examined the potentially different impacts associated with seabirds on the morphological, ultrastructural and molecular diversity of P. crispa. For that purpose, the present study analyzed four populations from the Hornsund Fjord area (West Spitsbergen) collected in the vicinity of planktivorous or piscivorous colonies and individual nests of seabirds. The morphological variability of P. crispa was studied using fresh samples, and it was documented with light microscopy as well as transmission and scanning electron microscopy. Populations were investigated by molecular analyses based on rbcL and 18S rRNA sequences. The differences in features measured were subjected to statistical analysis. This study provides new data concerning the macro- and submicroscopic structure and molecular diversity of P. crispa with regard to differences in humidity and the quantity of biogenic nutrients deposited by seabirds. Molecular research provided the first data about P. crispa from Spitsbergen. Birds’ diet is relevant for the quantity and quality of the provided nutrients, especially nitrogen compounds (planktivorous species) and phosphorus (piscivorous birds). Climate changes influence the quantitative structure of the colony, clearly favoring piscivorous birds. This, in turn, causes changes in the environment and vegetation. The obtained data on the P. crispa population may be compared with potential changes in the future.

Manganese accumulation by two species of Chara

Manganese accumulation by two species of Chara This paper reports the results of Mn accumulation in two species of green algae: Chara globularis and Chara hispida. The results of laboratory and field experiments show a rapid accumulation of Mn by charophytes and demonstrate that deposit formation on the plant surface in the so-called adsorption phase occurs in Mn accumulation. Both species can be an important factor in Mn circulation in lakes.

Phylogeography of Swertia perennis in Europe based on cpDNA markers

Background Swertia perennis(Gentianaceae) is a perennial diploid and clonal plant species that is discontinuously distributed in peat bogs in the mountains of Europe, Asia and North America as well as in the lowlands of Europe. The current geographical dispersion of S. perennis is probably the result of quaternary climatic changes that have played an important role in determining the distribution of Swertia and other plant and animal species. Methods In this study we used molecular techniques and combined data from chloroplast DNA markers (trnLF region and trnH-psbA spacer) to elucidate the phylogeography of S. perennis in Europe. Plants were collected from 28 populations in different locations in the lowlands and mountainous areas of Europe (e.g., the Carpathians, Sudetes, Bohemian Forest and Alps). cDNA was analysed to detect the genetic relationship between specimens from different locations. Results A total of 20 haplotypes were identified across the dataset. They were characterised by a high level of genetic variability but showed a lack of phylogeographical structure. This pattern may be the result of repeated recolonization and expansion from several areas. Such genetic differentiation may also be attributed to the relatively long-term isolation of S. perennis in Pleistocene refugia in Europe, which resulted in independent separation of different cpDNA phylogenetic lineages and variation in the nucleotide composition of cpDNA. Discussion The lack of strong phylogeographical structure makes it impossible to indicate the centre of haplotype diversity; however, refugia located in the Carpathians, Sudetes or Alps are the most probable sites where S. perennis existed in Europe. This lack of structure may also indicate a high level of gene flow in times when the landscape and fen systems were not fragmented in numerous geographically-isolated populations. This makes it difficult to speculate about the relationships between Asiatic and European plant populations and the origin and distribution of this species in Europe. Today, it seems to be restricted due to the occurrence of plants which clearly reflects the genetic variability from the ancient period.

Amplified fragment length polymorphism (AFLP)-based differentiation of selected Chara species

Abstract Charophytes are a group of green algae that grow in various types of water ecosystems and are characterized by a high degree of plasticity and morphological variation. To analyze the genetic diversity and taxonomic rank of several species from the genus Chara, the fingerprinting technique of Amplified Fragment Length Polymorphism (AFLP) was applied. We studied species that belong to sect. Grovesia (C. tenuispina, C. globularis, C. virgata, C. aspera and C. strigosa) and two species from the sect. Hartmania (C. intermedia and C. hispida). The individuals were collected in the field in north-eastern, central and eastern Poland. The species were identified based on morphological features and then analyzed using the AFLP fingerprinting method. UPGMA clustering and PCA analysis as well as morphological analysis revealed a clear separation of C. tenuispina and C. globularis, which formed separate clusters supported by high bootstrap values. Therefore, these species were distinguish as separate taxa, rather than varieties of C. globularis. Similarly, C. virgata also formed a separate cluster, thereby confirming that this taxon is a separate species, rather than a variety of C. globularis. The AFLP analysis did not show any differentiation between C. aspera and C. strigosa. The presented results do not fully support the taxonomic interpretation for the existence of several polymorphic species with numerous variations and forms, however, in some examples, the distinctive nature of the reproduction system may be used as a distinguishing feature of the taxa.