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Using a root vole Microtus oeconomus (Pallas, 1776) population in NE Poland we applied 31 microsatellite markers previously developed for root voles and closely related species, with the aim to improve the population genetic tools in this species. Here we present 16 polymorphic microsatellite markers grouped into four sets suitable for simultaneous amplification and genetically sex identification in M. oeconomus. The number of alleles per locus in 227 individuals varied from 7 to 26 with a low frequency of null alleles, expected heterozygosity ranged from 0.758 to 0.927, and observed heterozygosity from 0.722 to 0.947. Two loci showed significant deviation from Hardy-Weinberg equilibrium (p<0.05) and all loci showed independent inheritance. We expect these markers to be useful for studies of genetic population structure and kinship of M. oeconomus populations.
Human activity has led to severe bottlenecks in many wildlife species in the recent past. This usually increases the strength of genetic drift, leading to loss of genetic variation. Gene flow may however counteract the genetic consequences of small population size. Using 11 of 38 tested microsatellite loci and five moose populations in eastern Poland, we investigated the effects of two phenomena: bottlenecks that occurred in the nineteenth century and the first half of twentieth century, and admixture after moose populations expanded demographically and spatially in eastern Poland after the Second World War. The statistical tests indicated a recent bottleneck in all the studied samples with respect to H E and low Garza–Williamson index values. The Biebrza population, which consists of autochthonous moose representing a branch of the Central Europe mitochondrial DNA (mtDNA) clade and immigrants belonging to the Ural clade, is one of the most variable populations of this species. AMOVA, PCA, and STRUCTURE analyses all revealed significant population structuring, with most probable existence of K = 2 genetically distinct clusters that exhibited a relatively high level of admixture. Analysis of recent dispersal rates demonstrated that population from the Biebrza Valley may supply individuals to the other four studied moose populations. We also found female-biased sex ratio in nonharvested moose populations inhabiting eastern Poland.
Studies were conducted in the Department of Applied Entomology at Warsaw University of Life Sciences, in laboratory conditions. The aim of this study was to determine mutual effect of western flower thrips (Frankliniella occidentalis Pergande) and two-spotted spider mite (Tetranychus urticae Koch) on selected biology parameters on cucumber plants trited with biostimulators Asahi SL and Siapton 10 L. It was found the significant decrease of fecundity of western flower thrips females on cucumber leaves infested by two-spotted spider mite, specialy in the case of strong infestation. An application of biostimulators had a additional negative influence on western flower thrips fecundity and time of larvae hatching. The fecundity of two-spotted spider mite females, feeding on the cucumber leaves injured by thrips was lower as compared to healthy leaves. An application of biostimulators increased number of eggs laid by females on the leaves taken from sprayed plants as compared to control, in both infested and not infested by western flower thrips.
Badano wpływ masy odważki, czasu naparzania oraz dodatku soku cytrynowego i kwasu cytrynowego na zawartość Zn, Cd, Mn, Cu, Ni i Pb w naparach herbacianych. Ponadto określono stężenie w/w pierwiastków w suszu herbacianym i ich procent ługowania do naparu.
In recent years, human activity directly and indirectly influenced the demography of moose in Poland. The species was close to extinction, and only a few isolated populations survived after the Second World War; then, unprecedented demographic and spatial expansions had occurred, possibly generating a very complex pattern of population genetic structure at the present-day margins of the species range in Poland. Over 370 moose from seven populations were collected from Poland, and partial sequences of the mitochondrial control region (mtDNA-cr; 607 bp) were obtained. In addition, the entire mtDNA cytochrome b gene (1,140 bp) and Y-chromosome markers (1,982 bp in total) were studied in a chosen set of individuals. Twelve mtDNA haplotypes that all belonged to the European moose phylogroup were recorded. They could be divided into two distinct clades: Central Europe and the Ural Mountains. The first clade consists of three distinct groups/branches: Biebrza, Polesie, and Fennoscandia. The Biebrza group has experienced spatial and demographic expansion in the recent past. Average genetic differentiation among moose populations in Poland at mtDNA-cr was great and significant (Φ ST = 0.407, p < 0.001). Using mtDNA-cr data, four separate groups of population were recognized using spatial analysis of molecular variance and principal coordinate analysis, including a relict population in Biebrza National Park, a reintroduced Kampinos National Park population, as well as populations that were descendants of moose that colonized Poland from the east (Lithuania, Belarus, and Ukraine) and the north (former East Prussia). Among all the sequenced Y-chromosome markers, polymorphisms were found in the DBY14 marker in three populations only; four haplotypes were recorded in total. No significant differentiation was detected for this Y-linked marker among moose populations in Poland. Our mtDNA study revealed that a variety of different factors—bottleneck, the presence of relict, autochthonous populations, translocations, limited female dispersal, and the colonization from the east and north—are responsible for the observed complex pattern of population genetic structure after demographic and spatial expansion of moose in Poland.
Effects of cervid browsing on timber production, especially during winter, lead to economic losses in forest management. The aim of this study was to present an efficient DNA-based method which allows qualitative assessment of the winter diet from stools of moose (Alces alces), roe deer (Capreolus capreolus), and red deer (Cervus elaphus). The preliminary results of the diet composition of the three cervids from Poland were also presented with a special emphasis on moose. The electropherograms of the chloroplast intron trnL (UAA) P6 loop amplification products using g (fluorescence-labeled) and h primers revealed differences in the length of PCR products among various plant species eaten by these herbivores. In addition, the usage of species-specific primers allowed unambiguous identification of different gymnosperms and angiosperms. The preliminary moose diet analysis, based on winter fecal samples from the entire range of moose occurrence in Poland, revealed the presence of 15 to 24 tree, shrub, and herbaceous species. This fast, cost-efficient, and simple method proved also to be reliable for the diet analysis of red deer and roe deer. It may be a valuable tool in forest and conservation management, as well as a way of enhancing ecological studies focusing on the impact of herbivores on the ecosystems and their possible food niche overlap.
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