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1.
A. V. Khalin 《Entomological Review》2009,89(4):399-406
The structure of the claspettes (modified projections in the male genitalia) in species of the subgenus Ochlerotatus Lynch Arribalzaga of the genus Aedes Meigen is described in detail. A thorough investigation of the three-dimensional structure of the claspettes is necessary for identification of the Ochlerotatus species from Russia. The study of 30 species of Ochlerotatus demonstrated that frequently the use of the claspette structure as a diagnostic character was incorrect when the claspettes were described as flat structures. Examination of the three-dimensional structure of the claspettes has revealed characters differentiating Aedes diantaeus, A. intrudens and A. pullatus; A. communis, A. punctor, and A. hexodontus; A. annulipes, A. excrucians, and A. euedes, as well as some other species. 相似文献
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A. V. Khalin 《Entomological Review》2009,89(9):1137-1153
Additional diagnostic characters of the three-dimensional structure of the male genitalia revealed with the use of scanning
electron and light microscopy allowed elaborating a key to Aedes species from northwestern Russia. The key includes 29 species of 5 Aedes subgenera known or possibly occurring in the region. 相似文献
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E. B. Vinogradova 《Entomological Review》2011,91(6):729-734
The study of sex ratio in larval populations in the urban mosquito Culex pipiens pipiens f. molestus inhabiting underground sites in St. Petersburg was carried out for the first time in 1997–2001, as part of monitoring of local populations of this mosquito in order to estimate its reproductive potential. Samples of the immature stages were regularly collected in the underground breeding places flooded with water with a varying degree of pollution in five city districts (altogether 27 samples, 14 251 larvae). Pupation was observed under laboratory conditions at 20°C for 6–46 days. The sex was determined at the pupal stage. In 19 samples collected in basements of dwelling houses the incidence of males widely varied from 40.2 to 65.6%, and the sex ratio (males: females), from 0.7: 1 to 1.9: 1. Medians defining the percentage of males in the populations in different basements during a certain period (from 3 to 11 months) were 57.5%, 47.0%, and 50.2%. The greatest incidence of males (the median being 62.2%) and sex ratio from 1.1: 1 to 3: 1 was observed in autumn in 1999–2001 in populations inhabiting the sewer pipe. Analysis of all the 27 samples showed that the males constituted on the average 54.5%, i.e., that is the sex ratio was close to the normal value of 1: 1. Such important population characteristics as normal sex ratio at the pupal stage and the high autogeny rate are indicative of high reproductive potential of the urban mosquito in St. Petersburg. The hydrotechnical (mostly drainage of basements) and special mosquito control measures are needed to decrease mosquito abundance and restrict their further dispersal within the city. 相似文献
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Philomena Bodensteiner 《Mycological Progress》2007,6(4):221-228
Maireina afibulata and M. attenuatipilis are proposed as new members of the recently revised genus Maireina, one of the few anatomically well-studied cyphelloid groups in the Basidiomycota. Maireina species have brownish basidiomes, smooth, parietally unpigmented spores, and are characterized by non-ramified external hyphae with more or less thick, yellow to brown cell walls and distinct crystalline incrustations that always include their distal ends. A key to the species of the genus Maireina is presented, and M. afibulata as well as M. attenuatipilis are described and discussed in detail. Taxonomic novelties: Maireina afibulata Bodensteiner, M. attenuatipilis Bodensteiner 相似文献
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Terasawa Y Rahman SM Takata K Ikeda TM 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(1):143-151
Hordoindoline (Hin) genes, which are known to comprise Hina, Hinb-1, and Hinb-2, are associated with grain hardness in barley. However, the interspecific variation in the Hin genes in the genus Hordeum has not been studied in detail. We examined the variation in Hin genes and used it to infer the phylogenetic relationships between the genes found in two H. vulgare subspecies (cultivated barley and H. vulgare subsp. spontaneum) and 10 wild relatives (H. bogdanii, H. brachyantherum, H. bulbosum, H. chilense, H. comosum, H. marinum, H. murinum, H. patagonicum, H. pusillum, and H. roshevitzii). The Hina and Hinb genes of these species were amplified by PCR. We found two Hinb genes in three wild species (H. bogdanii, H. brachyantherum, and H. roshevitzii) and preliminarily named them Hinb-A and Hinb-B. Cluster analysis showed that the 17 Hinb genes present in Hordeum formed two distinct clusters (named A and B). Seven Hinb genes were included in Cluster-A, and 10 Hinb genes were included in Cluster-B. All Hinb-A genes were included in Cluster-A, while all of the Hinb-B genes were included in Cluster-B. In contrast, the Hinb-1 and Hinb-2 genes in H. vulgare were included in Cluster-B. These results suggest that the Hinb genes duplicated during the early stages of diversification in the genus Hordeum. On the other hand, the Hinb-1 and Hinb-2 genes in H. vulgare seem to have been generated by a duplication of the Hinb gene after the split of the lineages leading to H. vulgare and H. bulbosum. 相似文献
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A. Kh. Tambiev S. G. Vasilieva A. A. Lukyanov 《Moscow University Biological Sciences Bulletin》2011,66(4):133-137
The salt tolerance of two representatives of genus Spirulina (Arthrospira) Spirulina platensis and Spirulina maxima has been investigated. They both are the wide-spread objects of photobiotechnology and it has been shown that the content of 5–15 % sea-water in medium has not caused the decreasing of biomass yield more than 15–20% as compared with control. The further decreasing of biomass was proportionate to sea-water content in medium. The investigation of reactivity of native (intravital) exometabolites secreted into cultural medium has showed that the sea-water content influence the oxidative activity (OA) of exometabolites and hour’s rhythmics. 相似文献
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Fourteen new species of palms (Arecaceae) from Madagascar are described and named, based on material collected over the last 15 years. Twelve species belong to the genus Dypsis, namely D. andilamenensis Rakotoarin. & J. Dransf., D. anjae Rakotoarin. & J. Dransf., D. betsimisarakae Rakotoarin. & J. Dransf., D. culminis Rakotoarin. & J. Dransf., D. dracaenoides Rakotoarin. & J. Dransf., D. gautieri Rakotoarin. & J. Dransf., D. gronophyllum Rakotoarin. & J. Dransf., D. jeremiei Rakotoarin. & J. Dransf., D. metallica Rakotoarin. & J. Dransf., D. reflexa Rakotoarin. & J. Dransf., D. sancta Rakotoarin. & J. Dransf. and D. vonitrandambo Rakotoarin. & J. Dransf. and two species belong to the genus Ravenea: R. beentjei Rakotoarin. & J. Dransf. and R. hypoleuca Rakotoarin. & J. Dransf. Despite the fact that most of these species have been recorded from protected areas that are difficult to access in the eastern region of Madagasacar, they are all threatened. Based on IUCN categories and criteria, seven are Critically Endangered and seven are Vulnerable. 相似文献
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The classification methodology based on morphometric data and supervised artificial neural networks (ANN) was tested on five fly species of the parasitoid genera Tachina and Ectophasia (Diptera, Tachinidae). Objects were initially photographed, then digitalized; consequently the picture was scaled and measured by means of an image analyser. The 16 variables used for classification included length of different wing veins or their parts and width of antennal segments. The sex was found to have some influence on the data and was included in the study as another input variable. Better and reliable classification was obtained when data from both the right and left wings were entered, the data from one wing were however found to be sufficient. The prediction success (correct identification of unknown test samples) varied from 88 to 100% throughout the study depending especially on the number of specimens in the training set. Classification of the studied Diptera species using ANN is possible assuming a sufficiently high number (tens) of specimens of each species is available for the ANN training. The methodology proposed is quite general and can be applied for all biological objects where it is possible to define adequate diagnostic characters and create the appropriate database. 相似文献
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Following a re-examination of the material treated under Barleria brevispina (Fiori) Hedrén in the recent Flora of Somalia account of the Acanthaceae, it is concluded that two distinct species are involved and Barleria compacta Malombe & I. Darbysh. is described here from north-eastern Somalia. Its affinities and conservation status are discussed. 相似文献
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A. A. Kruglikova 《Journal of Evolutionary Biochemistry and Physiology》2011,47(6):534-542
The present study deals with molecular nature and peculiarities of the functioning of two main protective systems of larvae Lucilia sericata—the antimicrobial compounds of haemolymph and exosecretion released by feeding larvae into environment. In the haemolymph of larvae undergone to bacterial infestation, the chromato-masspectrometry methods identified a set of inducible antibacterial peptides including defensins (3844, 4062, and 4117 Da), P-peptide (3043 Da), and four new polypeptides (3235, 3702, 3746, and 3768 Da). The exosecretion of Lucilia sericata maggots contains the peptides analogous or identical to the haemolymph antimicrobial peptides (diptericins: 8882 Da and 9025 Da), high molecular compounds of the peptide nature (6466 Da, 6633 Da, 5772 Da, 8631 Da, etc.) differing from the known haemolymph components, and the low molecular compounds (130–700 Da). The spectrum of exosecretion bactericidal activity includes the representatives of various groups of bacteria including pathogen the most actual from the medical point of view-the methicillin-resistant Staphylococcus aureus that does not have anti-staphylococcal activity in contrast to haemolymph. The exosecretion components suppressing growth and development of this staphylococcus represent the substances of low molecular mass (from 160 to 1020 Da). The performed studies characterize the strategies used by “surgical maggots” for protection from pathogens and for suppression of microbial competitors, and allow better understanding of molecular mechanisms of larval therapy of purulent infectious diseases. These studies in perspective can serve the basis for creation of the principally new drugs for struggle with usual and antibiotics-resistant bacterial infections. 相似文献
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Dario Kremer Edith Stabentheiner Želimir Borzan Renata Jurišić Grubešić 《Biologia》2008,63(6):1111-1117
Micromorphological differences in leaves and pollen between two American (Fraxinus americana L., F. pennsylvanica Marshall) and two European (F. angustifolia Vahl, F. excelsior L.) ash species were studied using scanning electron microscope. The types, dimensions and distribution of characteristic trichomes were established and measured. Capitate hairs on the leaves had the same shape in all researched ash species. Acicular hairs were regularly present in two American ash species, but very rarely in the glabrous phase of F. angustifolia and F. excelsior. Only F. americana had coronulate abaxial surface of leaves. Pollen of F. angustifolia and F. excelsior had 3 (tricolpate) apertures, and F. americana and F. pennsylvanica 4 (stephanocolpate) apertures. Based on the appearance of the reticulum it’s possible to clearly distinguish all four species. F. angustifolia and F. pennsylvanica had muri with transversal ridges and seldom granules. Muri of F. excelsior and F. americana had slightly visible transversal ridges, and because of that noticeable granules. 相似文献
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R. Ramirez-Malagon I. Aguilar-Ramirez A. Borodanenko L. Perez-Moreno J. L. Barrera-Guerra H. G. Nuñez-Palenius N. Ochoa-Alejo 《In vitro cellular & developmental biology. Plant》2007,43(6):660-665
Mammillaria species are the most numerous within Cactaceae family, and some of them are threatened with extinction as a result of human activities. In this work, results of in vitro propagation are presented for ten Mammillaria species, testing 20 combinations of indole-3-acetic acid (IAA) and kinetin. Best results on shoot formation were obtained using kinetin at two levels: 27.9 and 46.5 μM. All IAA levels tested were able to induce de novo shoot formation in M. bocasana, M. densispina, M. hahniana, M. hutchisoniana, M. orcutii, M. pectinifera, M. perbella, M. picta, M. rhodantha, and M. zephyranthoides. Depending on the IAA level tested, four responding groups were observed concerning their highest shoot-formation number. For all species, the highest average of shoot formation was achieved with 5.7:46.5 or 11.4:46.5 μM IAA/kinetin, yielding 4.8 and 4.7 shoots per explant, respectively, in 60 d. Rooting of regenerated shoots was achieved by leaving the explants in their shoot-induction medium or transferring them to half-strength MS medium. Hardening of regenerated plants was successfully achieved by planting them in peat moss substrate after a desiccation treatment at room temperature for 3 d. 相似文献
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Two new species from the mountains of Altai and Tuva, Dolichopus fursovi Negrobov et Barkalov sp. n. similar to D. grunini Smirnov and D. selivanovae Negrobov et Barkalov, sp. n. similar to D. reichardti Stackelberg, are described. 相似文献