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  • Author: Monika Szczecińska x
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Recent data on occurrence the sporophytes in populations of dioecious moss, Nyholmiella obtusifolia in North-Eastern Poland

Moss Nyholmiella obtusifolia is relatively common in Poland, but mostly sterile specimens are found in herbarium collections. Sporogenes were created very rare. During bryological explorations conducted in NE Poland in 2009 - 2011, sporophytes were found in four populations of N. obtusifolia, which account for approximately 7% of the surveyed populations.

The reasons for low intrapopulation genetic variation in Lamium incisum Willd

The paper presents results of a study which aim was preliminary screening of intrapopulation genetic variability in Lamium incisum Willd. This weed species is rarely distributed in Poland and lessening its count during the last years. As a plant inhabiting anthropogenic sites it is exposed to extreme conditions and disturbances caused mostly by the progressive intensification of agriculture. In order to investigate the genetic variability of the selected population markers of ISSR category were used. The analysis of chosen individuals with use of three ISSR primers revealed total of 49 loci, of which only 15 were polymorphic. Nei's gene diversity index (HE=0.099) and the mean number of alleles per locus (AE=1.160) indicated low genetic diversity within the examined population. The research presented in this paper allows for a better learning of the genetic variability of the investigated species and considers probable factors influencing its level.

Abstract

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.

Abstract

Based on available molecular and morphological evidence, the genus Codriophorus P.Beauv. (Grimmiaceae subfam. Racomitrioideae) proved to be a polyphyletic taxon. It consists of two distinct genera which correspond to two sections of Codriophorus, namely sect. Codriophorus and sect. Fascicularia (Bednarek-Ochyra) Bednarek-Ochyra & Ochyra. The latter section is raised to generic rank as Dilutineuron Bednarek-Ochyra, Sawicki, Ochyra, Szczecińska & Plášek. The new genus consists of the following five species: D. fasciculare (Hedw.) Bednarek-Ochyra, Sawicki, Ochyra, Szczecińska & Plášek, comb. nov., D. brevisetum (Lindb.) Bednarek-Ochyra, Sawicki, Ochyra, Szczecińska & Plášek, comb. nov., D. anomodontoides (Cardot) Bednarek-Ochyra, Sawicki, Ochyra, Szczecińska & Plášek, comb. nov., D. corrugatum (Bednarek-Ochyra) Bednarek-Ochyra, Sawicki, Ochyra, Szczecińska & Plášek, comb. nov. and D. laevigatum (Mitt.) Bednarek-Ochyra, Sawicki, Ochyra, Szczecińska & Plášek, comb. nov.

Abstract

The traditionally conceived genera Orthotrichum Hedw. and Ulota F.Weber are here reclassified into six genera, Orthotrichum, Dorcadion Lindb., Nyholmiella Holmen & E.Warncke, Pulvigera Plášek, Sawicki & Ochyra, Plenogemma Plášek, Sawicki & Ochyra, and Ulota, based on morphological differences and partially on molecular evidence. The genus Pulvigera includes P. lyellii (Hook. & Taylor) Plášek, Sawicki & Ochyra (Orthotrichum lyellii Hook. & Taylor) which was selected as its generitype. The genus Plenogemma includes P. phyllantha (Brid.) Plášek, Sawicki & Ochyra (Ulota phyllantha Brid.) which was selected as its generitype.