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762. Fungi associated with Ips acuminatus (Coleoptera: Curculionidae) in Ukraine with a special emphasis on pathogenicity of ophiostomatoid species
- Creator:
- Davydenko, Kateryna, Vasaitis, Rimvydas, and Menkis, Audrius
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, borovice lesní, Scots pine, Coleoptera, Curculionidae, pine engraver beetle, Ips acuminatus, pathogens, Ophiostoma, Diplodia pinea, insect-fungus interaction, 2, and 59
- Language:
- English
- Description:
- Conifer bark beetles are well known to be associated with fungal complexes, which consist of pathogenic ophiostomatoid fungi as well as obligate saprotroph species. However, there is little information on fungi associated with Ips acuminatus in central and eastern Europe. The aim of the study was to investigate the composition of the fungal communities associated with the pine engraver beetle, I. acuminatus, in the forest-steppe zone in Ukraine and to evaluate the pathogenicity of six associated ophiostomatoid species by inoculating three-year-old Scots pine seedlings with these fungi. In total, 384 adult beetles were collected from under the bark of declining and dead Scots pine trees at two different sites. Fungal culturing from 192 beetles resulted in 447 cultures and direct sequencing of ITS rRNA from 192 beetles in 496 high-quality sequences. Identification of the above revealed that the overall fungal community was composed of 60 species. Among these, the most common were Entomocorticium sp. (24.5%), Diplodia pinea (24.0%), Ophiostoma ips (16.7%), Sydowia polyspora (15.1%), Graphilbum cf rectangulosporium (15.1%), Ophiostoma minus (13.8%) and Cladosporium pini-ponderosae (13.0%). Pathogenicity tests were done using six species of ophiostomatoid fungi, which were inoculated into Scots pine seedlings. All ophiostomatoid fungi tested successfully infected seedlings of Scots pine with varying degrees of virulence. Ophiostoma minus was the only fungus that caused dieback in inoculated seedlings. It is concluded that I. acuminatus vectors a species-rich fungal community including pathogens such as D. pinea and O. minus. The fungal community reported in the present study is different from that reported in other regions of Europe. Pathogenicity tests showed that O. minus was the most virulent causing dieback in seedlings of Scots pine, while other fungi tested appeared to be only slightly pathogenic or completely non-pathogenic., Kateryna Davydenko, Rimvydas Vasaitis, Audrius Menkis., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
763. Fusilade herbicide causes alterations in chloroplast ultrastructure, pigment content and physiological activities of peanut leaves
- Creator:
- Fayez, K. A., Radwan, D. E. M., Mohamed, A. K., and Abdelrahman, A. M.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, antioxidanty, photosynthesis, antioxidants, Arachis hypogeae, fusilade, lipid peroxidation, ultrastructure, 2, and 581
- Language:
- Multiple languages
- Description:
- Fusilade (fluazifop-p-butyl) is one of the herbicides that inhibit acetyl-CoA carboxylase. The exogenous effect of 30, 60, and 90 ppm fusilade on peanut (Arachis hypogaea L. cv. Giza 5) leaves was studied. With increasing fusilade concentration, the peanut leaf chlorosis appeared after 7-10 d. Declined leaf pigment contents confirmed the leaf chlorosis. Electron microscopic observation of the fusilade-treated (FT) leaves revealed disorganization in the ultrastructure of mesophyll cell chloroplasts. An increase of plastoglobuli occurrence within chloroplasts and degenerated grana thylakoids were observed in FT leaves. Fusilade treatments induced mainly the enhancement of malondialdehyde content and the activities of peroxidases (guaiacol and ascorbate). On contrary, a decrease in H2O2 content, catalase and superoxide dismutase activities was recorded. Enhancements of the guaiacol and ascorbate peroxidase activities were associated with the decreasing H2O2 content in the FT leaves. Hydrogen peroxide seems not to be involved in the oxidative stress of FT leaves. In the FT leaves, the oxidative stress confirmed by chlorophyll degradation and lipid peroxidation might be caused by the other reactive oxygen species probably due to the decrease of superoxide dismutase activity., K. A. Fayez, D. E. M. Radwan, A. K. Mohamed, A. M. Abdelrahman., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
764. Fylogeneze a vzájemné vztahy určují nejpřirozenější systém živočichů
- Creator:
- Jitka Vilímová
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Biologické vědy, fylogeneze, živočichové, phylogeny, animals, 2, and 57/59
- Language:
- Czech
- Description:
- Jitka Vilímová.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
765. Fylogeneze živočichů: ohlédnutí roku 2015
- Creator:
- Jan Zrzavý
- Format:
- bez média and svazek
- Type:
- article, text, články, journal articles, model:article, and TEXT
- Subject:
- Biologické vědy, biologie, fylogeneze živočichů, mnohobuněční, biology, animal phylogeny, Metazoa, molekulární fylogenetika, fylogenetická metodika, molekulární fylogeneze, fylogenetický přístup, 2, and 57/59
- Language:
- Czech
- Description:
- Článek přináší přehled současných znalostí o fylogenezi mnohobuněčných živočichů, tak jak vycházejí ze současného fylogenomického výzkumu. Zvláštní pozornost je věnována skupinám s konfliktním postavením (Ctenophora, Xenacoelomorpha, Bryozoa) a skupinám, o jejichž postavení dosud nevíme téměř nic (Dendrogramma, Dicyemida, Orthonectida)., We present an overview of current knowledge on the phylogeny of multicellular animals, based on current phylogenomic research. This overview pays special attention to groups with uncertain positions (Ctenophora, Xenacoelomorpha, Bryozoa) and groups whose position is still largely unknown (Dendrogramma, Dicyemida, Orthonectida)., and Jan Zrzavý.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
766. Fylogeografie rostlin střední Evropy
- Creator:
- Tomáš Fér and Karol Marhold
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Botanika, biogeografie, flóra, botanika, 2, and 58
- Language:
- Czech
- Description:
- Both molecular and palaeoecological methods enable us to study past changes in plant distribution. The results of recent phylogeographical studies have demonstrated that Central Europe was not only at a crossroads of postglacial migration routes, but also an area where many species might have survived during glacial periods. and Tomáš Fér, Karol Marhold.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
767. Fyzika a živé struktury: odkud povstávají mechanické vlastnosti živé hmoty
- Creator:
- Holeček, Miroslav, Kochová, Petra, and Tonar, Zbyněk
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- živé organismy, biofyzika, living organisms, biophysics, 2, and 577
- Language:
- Czech and English
- Description:
- Od dob, kdy Galileo Galilei položil základy matematického popisu přirozených procesů, musela fyzika projít ještě složitou cestu, než zacílila se vší vážností a energií tento popis na živé organismy. Neobyčejně smělý rozvrh Reného Descarta, jehož matematicky chápaná rozprostraněnost zahrnovala i živé organismy jakožto mechanismy podléhající stejným zákonům jako cokoli neživého, ovšem nenabízel žádnou cestu, jak fyziku systematicky provozovat. Tuto cestu vytyčil až Isaac Newton. Jeho program průzkumu fyzikální reality je však založen na zkoumání pohybů a hledání sil, které tyto pohyby odchylují od pohybu rovnoměrného a přímočarého. V tomto pojetí se tak živé organismy jeví jako prakticky nepřístupné nějakému fyzikálnímu průzkumu. Pojem pohybu chápaného jako geometrická trajektorie zde ztrácí svůj zásadní význam (je řada jiných podstatných "pohybů", jako růst či rozmanité změny vnitřní struktury) a pojem síly se stává problematickým (jaké "síly" zastaví pohybující se myš?). Až ve dvacátém století se fyzika začala vážně a systematicky zabývat i živými strukturami. Bylo to zejména díky rozvoji termodynamiky, molekulární fyziky, počítačových simulací a vysoce sofistikovaných experimentálních a zobrazovacích metod., The paper deals with living matter (living tissues and individual cells) from the point of view of physics. It passes through several upůto-date approaches that are clearly physical. Starting with thermodynamics that brings us to study the free-energy dependence on microscopic parameters of living tissues, we continue with special mechanical properties of living cells and the important role of pre-stress in their "skeleton". We mention the "tensegrity approach" and review briefly the approach in which a cell is understood as a soft glassy material. Then we discuss problems of description and experimental identification of properties of living tissues and present an example outlining a pure mechanical explanation how smooth muscle cells may efficiently control mechanical behaviour of the whole tissue. The concluding discussion tries to elucidate the role of physics in understanding the secret of life., Miroslav Holeček, Petra Kochová, Zbyněk Tonar., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
768. Gaisleria monodactyloptera - nový druh létavého savce?
- Creator:
- Milan Klíma
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, netopýři, zoology, bats, 2, and 59
- Language:
- Czech
- Description:
- Milan Klíma.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
769. Gas exchange of terrestrial and epiphytic orchids from Brazilian Atlantic Rainforest
- Creator:
- Pires, M. V., Almeida, A.-A. F., Santos, E. A., and Bertolde, F. Z.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, epiphytes, net photosynthetic rate, orchids, photosynthesis, stomatal conductance, terrestrial, transpiration, 2, and 58
- Language:
- Multiple languages
- Description:
- Leaf gas exchange of terrestrial and epiphytic orchids from the Atlantic Rainforest in northeast Brazil was investigated under artificial growth conditions. The terrestrial orchids showed higher values of all photosynthetic parameters in comparison to epiphytic ones. There was a close relationship between PN and gs for both terrestrial and epiphytic orchids. Taken together, our results demonstrated that the photosynthetic parameters were related to the specific growth habits of the orchids under study., M. V. Pires ... [et al.]., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
770. Gas exchange patterns in Platynus assimilis (Coleoptera: Carabidae): Respiratory failure induced by a pyrethroid
- Creator:
- Kivimägi, Irja, Kuusik, Aare, Ploomi, Angela, Metspalu, Luule, Jogar, Katrin, Ingrid H. (Ingrid Helvi) Williams, Sibul, Ivar, Hiiesaar, Külli, Luik, Anne, and Mänd, Marika
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Carabidae, Platynus assimilis, alpha-cypermethrin, resting metabolic rate, non-target, respiration, 2, and 59
- Language:
- English
- Description:
- Discontinuous gas exchange (DGE) is the main (23 individuals) breathing mode in resting adult Platynus assimilis. Few of the beetles tested (13 individuals) displayed a pattern of cyclic gas exchange or CGE. The burst of CO2 release in DGE and CGE was always accompanied by abdominal pumping (active ventilation or V). Seven individuals displayed a pattern of continuous respiration, characterized by regular abdominal pumping. Resting metabolic rate (RMR) in continuously breathing beetles was higher than in those using DGE and CGE. After treatment with sub-lethal doses of alpha-cypermethrin DGE ceased. Treated beetles were characterized by continuous pumping and almost regular periods of activity. RMR increased significantly after treatment with a pyrethroid., Irja Kivimägi ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public