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First species record of Strigea falconis Szidat, 1928 (Trematoda, Strigeidae) from gyrfalcon Falco rusticolus in Iceland-pros and cons of a complex life cycle
Get PDFStrigea falconis is a common parasite of birds of prey and owls widely distributed in the Holarctic. We aimed to characterise S. falconis from Iceland via integrative taxonomic approach and to contribute to the understanding of its circulation in the Holarctic. We recovered adult S. falconis from two gyrfalcons (Falco rusticolus) collected in 2011 and 2012 in Iceland (Reykjanes Peninsula, Westfjords) and characterised them by morphological and molecular genetic (D2 of rDNA, cox1, ND1 of the mDNA) methods. We provide the first species record of S. falconis in Iceland which to the best of our knowledge is its northernmost distributional range. The presence of S. falconis in Iceland is surprising, as there are no suitable intermediate hosts allowing completion of its life cycle. Gyrfalcons are fully sedentary in Iceland; thus, the only plausible explanation is that they acquired their infection by preying upon migratory birds arriving from Europe. Our data indicate that the most likely candidates are Anseriformes and Charadriiformes. Also, we corroborate the wide geographical distribution of S. falconis, as we found a high degree of similarity between our haplotypes and sequences of mesocercariae from frogs in France and of a metacercaria from Turdus naumanni in Japan, and adults from Buteo buteo and Circus aeruginosus from the Czech Republic. The case of Strigea falconis shows the advantages of a complex life cycle and also depicts its pitfalls when a parasite is introduced to a new area with no suitable intermediate hosts. In Iceland, gyrfalcons are apparently dead-end hosts for S. falconis.OA-hybri
Tests in the course Open source tools for text processing
No full textV rámci projektu Innovative Open Source Courses for Computer Science Curriculum je řešen kurz zabývající se zpracováním textů pomocí počítače. V pilotním běhu v rámci aktivit projektu byly aplikovány vybrané kapitoly kurzu a v závěru výuky byl realizován stručný test, jehož cílem bylo zjistit impakt dané výuky i možnosti konstrukce podobných testů rozšířené na kompletní obsah kurzu.It is being solved within the project Innovative Open Source Courses for Computer Science Curriculum computer-based word processing course. In the pilot run as part of the project activities, selected chapters of the course were applied and at the end of the lesson a short test was implemented, the aim of which was to determine the impact of the given lesson and the possibility of constructing similar tests extended to the complete content of the course.Published Versio
Nature-Based Management of Lawns-Enhancing Biodiversity in Urban Green Infrastructure
Get PDFUrban green areas have multifunctional benefits that may mitigate unfavorable health and ecological effects. Green areas represent important biodiversity hideouts in anthropogenic regions. Lawns are the most common elements of urban greenery, covering a considerable number of green areas in cities. The aim of this analysis was to gain knowledge on urban greenery and elaborate recommendations related to management that favors grass lawn biodiversity. The established working hypothesis is that the limited intensity of management in urban grass areas is reflected in the modification of their species composition, as well as their potential ecological functions. An experiment on the management of city lawns was conducted in 2010 (still ongoing). There are three lawn variants under different management methods: ornamental, city, and permaculture lawns. Vegetation was assessed using the method of phytocoenological relevés. The coverage values of the individual plant species were processed using multidimensional analysis of ecological data. The results showed that human decisions and activities affected the species composition of these grassy areas. There were 46 plant taxa found during the monitoring: 12 in ornamental lawn variants, 24 in city lawn variants, and 31 in permaculture lawn variants. Permaculture lawns with extensive management represent the most environmentally friendly variant with respect to biodiversity and soil moisture content. However, changes in species composition have raised questions regarding the extent to which they may perform other ecosystem functions. Increasing the intensity of lawn management has resulted in lower plant diversity. Extensive management alters the aesthetic value of lawns and creates spaces for species that may spread in urban environments.O
Evaluation of the Selectivity and Efficiency of Synthetic Sex Pheromones of Leaf-Rollers from Different Manufacturers
Get PDFIn 2019 (May-September), the efficiency of pheromone lures for Grapholita funebrana Treitschke, 1835 and Pandemis heparana (Denis & Schiffermüller, 1775) from two manufacturers (Propher, Pherobank) were compared. Monitoring was performed in three study areas in South Moravia (Czech Republic): Kyjov (faunistic square 6968), Brno-Soběšice (6765) and Brno-Starý Lískovec (6865). A total of 14 pheromone traps, from both companies, were suspended. Both target species were found in the traps, with Grapholita funebrana present in all study areas (a total of 5107 adults) and Pandemis heparana was found in Kyjov (64 adults). Furthermore, 2061 individuals of non-target species from the Autostichidae, Noctuidae, Tortricidae and Yponomeutidae families were captured. And 7 non-target species were captured using the pheromone for G. funebrana, most numerously Grapholita molesta (Busck, 1916), Cnephasia stephensiana (Doubleday, 1849) and Argyresthia trifasciata Staudinger, 1871; while, only two non-target species were identified using the pheromone for P. heparana, Noctua fimbriata (Schreber, 1759) and Yponomeuta malinellus Zeller, 1838. Compared to Propher pheromones, Pherobank pheromones were more attractive for target species and less attractive for non-target species.O
Redescription of Diastolaimus grossus (Truskova & Eroshenko, 1977) Andrassy, 1984 (Rhabditida, Chambersiellidae) from Europe and comments on its phylogenetic position
Get PDFTwo populations of the species Diastolaimus grossus have been obtained from bark of trees in Bosnia and Herzegovina and the Czech Republic. The species is described and characterized in detail using morphological techniques (light and electron scanning microscopy) and morphometrical (Gower General Similarity coefficient of morphological characters) and molecular analyses, including phylogenetic analysis of all related and already sequenced species of the family Chambersiellidae. Morphological and molecular analyses, based on 18S and 28S ribosomal DNA sequences, show that the family Chambersiellidae is polyphyletic, being the subfamily Chambersiellinae related with Cephalobomorpha and Tylenchomorpha, and the subfamily Macrolaiminae is located into Panagrolaimomorpha. The genus Diastolaimus, previously belonging to Macrolaiminae, is transferred to Chambersiellinae. Diastolaimus mexicanus is proposed as a junior synonym of D. grossus.OA-hybri
Molecular Characterization of 'Candidatus Phytoplasma prunorum' in the Czech Republic and Susceptibility of Apricot Rootstocks to the Two Most Abundant Haplotypes
Get PDF'Candidatus Phytoplasma prunorum' is one of the most destructive pathogens of Prunus species, where susceptible species render unproductive several years after infection. In epidemiology, the molecular characterization of phytoplasmas is based on sequence analysis of variable nonribosomal genes. In this study aceF, pnp, imp and secY genes were used for characterization of the 'Ca. P. prunorum' genotypes present in the Czech Republic. In total, 56 plant and 33 vector (Cacopsylla pruni) samples positive to 'Ca. P. prunorum' collected in seven localities were used in the study. Based on sequence analysis, four aceF, two pnp, six imp, and three secY genotypes were identified in analyzed samples. The most abundant in both plant and insect samples were the A6, P2, I4, and S2 genotypes. Most of the Czech 'Ca. P. prunorum' haplotypes clustered together in the haplotype network analysis. Next, two isolates representing the two most abundant Czech haplotypes (A6-P2-I4-S2 and A5-P2-I4-S2) were used in the susceptibility test of three apricot rootstock types (St. Julien A, M-VA-1, GF-305). Susceptibility was analyzed by phytoplasma quantification using quantitative real-time PCR and evaluation of symptom manifestation. Based on the results, the influence of the rootstock type on the phytoplasma titer and symptom manifestation was greater than of the phytoplasma isolate, while the year of analysis had no influence on the results. The results also showed that the phytoplasma titer is increasing in plant tissues during the vegetation period.O
Distribution of pesticides in agroecosystem food webs differ among trophic groups and between annual and perennial crops
Get PDFPesticides threaten biodiversity, but we know little about how they permeate food webs. Few studies have investigated the number, concentration, and composition of pesticides in agroecosystem food webs even though agroecosystems cover one-third of Earth's land area. We conducted a pioneering study on the distribution of pesticides across local (i.e., on farm) and meta food webs (i.e., regional pool of local food webs) within both perennial (N = 8) and annual crops (N = 11), examining four trophic groups-soil (primary resource), plants (primary producers), rodents (herbivores), and spiders (predators)-for the presence of multiple residues, and comparing these findings to pesticides applied by farmers in recent years. We also undertook interviews with farmers to obtain the most precise information about pesticide applications in their fields. We detected a wide spectrum of pesticides in both annual and perennial crop types. Pesticides applied by farmers represented only a small proportion of all detected pesticides, indicating that pesticides entered local food webs from surrounding landscapes. Some detected pesticides had been banned by the European Union several years ago, which is highly alarming. Trophic group mobility and crop type drove pesticides number at local scale, as mobile groups contained larger numbers of pesticides (probably from encountering wider spectra of pesticides). At a meta scale, spiders contained the highest number of detected pesticides in perennial crops but lowest diversity in annual crops. This might be explained by how spiders' functional traits are selected in different crops. Insecticides and fungicides concentrations mostly increased with trophic level, indicating bioaccumulation. Herbicides concentration were highest in plants suggesting (bio)degradation. As bioaccumulation outweighed (bio)degradation, pesticides increased overall with trophic level. Therefore, the distribution of pesticides in agroecosystem food webs was affected simultaneously by several mechanisms and depended upon trophic group, crop type, and, probably, surrounding landscape.OA-hybri
Semantic segmentation of plant roots from RGB (mini-) rhizotron images-generalisation potential and false positives of established methods and advanced deep-learning models
Get PDFBackground Manual analysis of (mini-)rhizotron (MR) images is tedious. Several methods have been proposed for semantic root segmentation based on homogeneous, single-source MR datasets. Recent advances in deep learning (DL) have enabled automated feature extraction, but comparisons of segmentation accuracy, false positives and transferability are virtually lacking. Here we compare six state-of-the-art methods and propose two improved DL models for semantic root segmentation using a large MR dataset with and without augmented data. We determine the performance of the methods on a homogeneous maize dataset, and a mixed dataset of > 8 species (mixtures), 6 soil types and 4 imaging systems. The generalisation potential of the derived DL models is determined on a distinct, unseen dataset. Results The best performance was achieved by the U-Net models; the more complex the encoder the better the accuracy and generalisation of the model. The heterogeneous mixed MR dataset was a particularly challenging for the non-U-Net techniques. Data augmentation enhanced model performance. We demonstrated the improved performance of deep meta-architectures and feature extractors, and a reduction in the number of false positives. Conclusions Although correction factors are still required to match human labelled root lengths, neural network architectures greatly reduce the time required to compute the root length. The more complex architectures illustrate how future improvements in root segmentation within MR images can be achieved, particularly reaching higher segmentation accuracies and model generalisation when analysing real-world datasets with artefacts-limiting the need for model retraining.O
Assessment of the effect of optimised field plot size on the crop yield
Get PDFThe presented research deals with the effect of plot size changes on the crop yield. Three plots were chosen in a company engaged in conventional agriculture, on which yields were monitored from 2019 using yield maps. In 2020, the plots (initial size > 30 ha) were divided into different parts sized < 30 ha. In 2021, these newly arisen parts of the plots were harvested. Changes in the yield of grown crops were analysed using yield maps acquired by the harvesting machines. Relative yields (%) and absolute yields (t/ha) were determined on all experimental land parts arising from the initial plots' division. The values were then compared with yields recorded before the division of individual plots using zonal statistics. Measured relative yield values clearly show (P < 0.05) that the division of plots resulted in the increased heterogeneity of crop yields. On the initial plots as well as on the newly arisen plots, the relative yield was divided into the following categories: < 70, 70-85, 85-95, 95-105, 105-115, 115-130 and > 130%, with the value of 100% representing average yield. The analysis of measured yield data showed that the division of plots into smaller parts resulted in an uneven yield distribution because if a divided plot was heterogeneous in terms of yield levels, a cumulation of "higher yield levels (> 100%)" could have occurred in one specific newly arisen plot at the expense of another one. Moreover, new marginal parts of lands came into being during the division of larger soil complexes, and hence zones with potentially reduced yields.O
Spatial distribution of saproxylic beetles on trunks of standing Scots pine trees
Get PDFThe spatial distribution of saproxylic beetles landing and climbing stems of 12 grown and healthy Scots pine trees (Pinus sylvestris L.) was examined in detail during a 3-year trial. The beetles were sampled using sticky traps attached to the tree trunk at three tree parts (i.e., the trunk base, middle part of the trunk, and trunk in crown). Each tree part was sampled using two sticky traps facing opposite cardinal directions (north and south). In total, 4063 individuals representing 169 taxa of saproxylic beetles were yielded in the 1405 obtained samples. Remarkable interstrata diversification of saproxylic beetle assemblages reflecting distribution of breeding substrates in the forest stand was observed. Overall, species richness decreased considerably from the trunk base to the crown, with intermediate values for the middle part of the trunk. However, the abundance of mycetophages and saproxylophages decreased from the trunk base to the crown, with xylophages being the most abundant in the tree crown. The cardinal direction exhibited overall weak effects on abundance, species richness, and composition, but the occurrence of a few particular species was significantly associated with the south (13 species) or north (3 species) facing part of the trunk. Our results suggest that primary attraction and random landing strategies are combined during the substrate selection by many species. High variability in the importance of the studied explanatory variables was observed among taxa, which shows how the species composition recorded in any study might alter its general outcomes.OA-hybri