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332. Hořavka duhová - z parazita hostitel
- Creator:
- Martin Reichard
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, ryby, obojživelníci, plazi, parazitologie, fishes, amphibians, reptiles, parasitology, 2, and 59
- Language:
- Czech
- Description:
- Hořavky (rod Rhodeus) jsou drobné kaprovité ryby, které kladou jikry do žaberního aparátu sladkovodních velevrubovitých mlžů (Unionidae). Rod má hlavní centrum rozšíření ve východní Asii, kde žijí asi dvě desítky druhů, ale jeden druh - hořavka duhová (R. amarus) - se vyskytuje také na našem území. Hořavky jsou vzhledem ke své reprodukční strategii vděčným modelem pro studium pohlavního výběru a vztahů mezi parazity a jejich hostiteli. Díky výzkumu v uplynulých letech došlo ke znatelnému posunu v našem porozumění toho, jak si samci a samice vybírají své partnery, jaké má tento výběr dopady na intenzitu pohlavního výběru a demografické parametry, nebo jak hořavky kolonizovaly Evropu. Asi nejzajímavější novinky se týkají výzkumu koevolučního vztahu mezi hořavkami a jejich hostitelskými mlži a vlivu nepůvodního druhu hořavky očkaté (Rhodeus ocellatus) a mlžů (škeble asijská - Sinanodonta woodiana a slávička mnohotvárná - Dreissena polymorpha) na tento vztah., Bitterlings (Rhodeus) are small cyprinid fishes of East Asian origin, remarkable for their reciprocal association with unionid mussels. Updated knowledge on the presence of European Bitterling (R. amarus) in Europe throughout the Holocene, based on data from bibliographical sources and genetic methods, is presented. The current state of the coevolutionary arms race between bitterling and mussels in areas of ancient and recent sympatry is reviewed. New challenges faced by the European Bitterling are addressed that come from the occurrence of non-native species such as the Asian unionid mussel Sinanodonta woodiana, Zebra Mussels (Dreissena polymorpha) and Asian Rosy Bitterling (R. ocellatus)., and Martin Reichard.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
333. Hoře, hořce, hořečky. V. Hořký osud hořepníků
- Creator:
- Zdenka Křenová
- Type:
- article, model:article, and TEXT
- Subject:
- Zoologie, zoologie, botanika, fyziologie rostlin, pěstitelství, životní prostředí, ekologie, botany, plant physiology, horticultural education, environment, ecology, 2, and 59
- Language:
- Czech
- Description:
- Hořec hořepník (Gentiana pneumonanthe) se vyskytuje v mírném pásu Evropy a jeho areál zasahuje až do oblasti jihozápadní Sibiře. Ve střední Evropě najdeme hořepník na nehnojených, střídavě vlhkých bezkolencových loukách a extenzivních pastvinách. V ČR i řadě okolních zemí je hořec hořepník považován za vzácný a ohrožený druh, a to přestože jde o vytrvalý, dlouhověký druh, který produkuje velký počet semen. Podobně jako řada dalších druhů se stal obětí odvodnění a radikálních změn ve způsobu obhospodařování krajiny. Pro zachování životaschopné populace hořce hořepníku je hlavní klíčení a přežívání semenáčků, které úspěšně probíhá pouze na ploškách s obnaženým půdním povrchem (gaps). Optimálně načasované kosení, pastva či nejlépe jejich kombinace jsou vhodným managementem hořepníkových lokalit a nadějí i pro kriticky ohroženého modráska hořcového (Phengaris alcon, dříve Maculinea alcon). Tento druh využívá hořce hořepníky u nás coby hlavní živnou rostlinu a dostatečně početná populace hořepníku je považována za jednu z hlavních podmínek výskytu modráska., Gentiana pneumonanthe occurs in the temperate zone of Europe, with its range extending to southwest Siberia. In central Europe, the species grows in oligotrophic wet meadows (Molinion) and extensive pastures. Plants are perennial, long-lived and produce many seeds. It is a rare and endangered species of the Czech flora and floras of many neighbouring countries; drainage of its sites and abandonment of traditional management practices are the major threats. Germination and seedling survival (the crucial phases of the species life cycle) are successful only in gaps with bare soil. Proper timing of mowing and grazing, or preferably their combination, are necessary for effective species conservation. They also give a chance to the Blue Alcon (Phengaris alcon, formerly Maculinea alcon), a monophagous butterfly feeding on Marsh Gentian. The Blue Alcon usually occurs only in large populations of its food-plant., Zdenka Křenová., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
334. Hoře, hořce, hořečky: Světoobčan hořeček nahořklý. IV
- Creator:
- Jiří Brabec
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, botanika, fyziologie rostlin, pěstitelství, botany, plant physiology, horticultural education, 2, and 59
- Language:
- Czech
- Description:
- Hlavním druhem posledního dílu horečkové části seriálu je hořeček nahořklý. Jde o široce rozšířený druh - Evropa, severní Asie až po střední Sibiř, Dálný východ, Severní Amerika. Počet lokalit a velikost populací tohoto druhu však v ČR v posledních dekádách dramaticky poklesl. V současné době je prokázán ze 71 lokalit (70 lokalit G. amarella subsp. amarella a jedna lokalita G. amarella subsp. lingulata). Z ČR je známo též několik horečkových kříženců. Do současnosti se zachovaly populace dvou z nich. U hořečků je známé synchronizované kolísání velikosti populací. V ČR lze tento jev dokumentovat na dvou druzích přežívajících dosud ve více populacích (G. praecox subsp. bohemica a G. amarella). Příčiny synchronizace nejsou známy. Jednou z hypotéz je masivní klíčení, růst a v dalším roce kvetení hořečků v mezerách nárazově vytvořených v jinak relativně zapojeném travním porostu. Synchronizované vytvoření mezer v porostu pak může být způsobeno přísuškem během vegetační sezóny., G. amarella is a widely distributed species (Europe, northern Asia to Central Siberia, the Far East and North America); however, the number of its sites and population size have decreased dramatically in the last few decades in the Czech Republic. At present, the species is documented from 71 sites here (70 sites of G. a. subsp. amarella, one site of G. a. subsp. lingulata). Several hybrids of Gentianella species are also known from the Czech Republic (two of them have survived so far). A synchronized inter-annual fluctuation in population size is documented for G. praecox subsp. bohemica and G. amarella in the Czech Republic. The reasons behind, however, remain unclear. Massive establishment, survival and flowering in the year following the creation of gaps in vegetation have been suggested as an explanation. Synchronized occurrence of gaps may be caused by a dry period during the growing season., Jiří Brabec., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
335. Horizontal transmission of the ectoparasite Gyrodactylus arcuatus (Monogenea: Gyrodactylidae) to the next generation of the three-spined stickleback Gasterosteus aculeatus
- Creator:
- Lumme, Jaakko and Ziętara, Marek S
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- konkurence, parazitické organismy, competition, parasitic organisms, clonal propagation, parasite transition, 2, and 59
- Language:
- English
- Description:
- In the parthenogenetic monogeneans of the genus Gyrodactylus Nordmann, 1832, the genetic diversity within or between hosts is determined by the relative roles of lateral transmission and clonal propagation. Clonality and limited transmission lead to high-amplitude metapopulation dynamics and strong genetic drift. In Baltic populations of the three-spined stickleback Gasterosteus aculeatus Linnaeus, the local mitochondrial diversity of Gyrodactylus arcuatus Bychowsky, 1933 is very high, and spatial differentiation weak. To understand the transmission dynamics in a single location, the transmission of the parasite from adults to next generation sticklebacks was investigated in a northern Baltic brackish water location. By sequencing 777 nt of cox1, as many as 38 separate mitochondrial haplotypes were identified. In August, the intensity of gyrodactylid infection on adult hosts was high, the haplotype diversity (h) was extreme and differentiation between fish was negligible (total h = 0.926, mean h = 0.938). In October, only 46% of the juvenile sticklebacks carried G. arcuatus. The number of parasites per young fish followed a Poisson distribution 0.92 ± 1.04 (mean ± SD) on October 2, and was clearly overdispersed 2.38 ± 5.00 on October 25. The total haplotype diversity of parasites on juveniles was nearly as high as in adults (h = 0.916), but the mean per fish was only h = 0.364 (FST = 0.60), due to low intensity of infection and rapid clonal propagation of early arrivals. The initial first come first served advantage of the first gyrodactylid colonisers will be lost during the host adulthood via continuous transmission. Nesting and polygamy are suggested as factors maintaining the high genetic diversity of the parasite population. The transmission dynamics and, consequently, the population structure of Baltic G. arcuatus is fundamentally different from that of G. salaris Malmberg, 1957, on the Baltic salmon Salmo salar Linnaeus., Jaakko Lumme, Marek S. Ziętara., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
336. Hormony a hormonální řízení antistresové odpovědi u hmyzu
- Creator:
- Dalibor Kodrík
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, hmyz, hormony, zoology, insects, hormones, 2, and 59
- Language:
- Czech
- Description:
- Hmyzí hormonální soustava se skládá z několika typů žláz produkujících tři různé druhy hormonů – ekdysteroidy, juvenilní hormony a peptidické neurohormony. Struktura, funkční koordinace a vzájemné vztahy v této soustavě představují dobře organizovaný řídicí systém, který v zásadě pracuje stejně jako hormonální soustava obratlovců: řídí prakticky všechny životní projevy hmyzu. Jedna skupina hmyzích metabolických neurohormonů – adipokinetické hormony – hraje důležitou roli v odpovědi organismu na stresové podmínky. Tyto hormony zajišťují mobilizaci energetických zdrojů, stimulují pohybovou aktivitu, zvyšují činnost srdce, aktivují imunitní systém a nedůležité procesy odsouvají na pozdější dobu. Touto koordinovanou činností umožňují hmyzímu organismu vyrovnávat se s nepříznivými podmínkami vnějšího prostředí a podílet se tak na udržování homeostázy vnitřního prostředí., The insect hormonal system consists of several types of endocrine glands which produce three different hormones – ecdysteroids, juvenile hormones and peptidic neurohormones. The structure, functional coordination and mutual relationships within the system are a well organised control system resembling the hormonal system of vertebrates: it controls practically all aspects of insect life. One group of insect metabolic neurohormones called adipokinetic hormones plays an important role in the defence of the insect organism against stress. Those hormones control energy mobilization, stimulate locomotory activity and the heart beat, activate the immune system and postpone less important processes for later. That sophisticated system helps the insect organism to cope with negative environmental conditions and to retain the body homeostasis., and Dalibor Kodrík.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
337. Hospodářský živočichopis pro školy rolnické a odborné hospodářské
- Creator:
- Tomáš Lenoch
- Publisher:
- Minist. zemědělství RČ
- Format:
- print, text, regular print, and 1 l., 192 s. : 255 obr. ; v. 8°
- Type:
- model:monograph and TEXT
- Subject:
- Zoologie, zoologie, živočichové, zvířata, 59, 2, and UL01
- Language:
- Czech
- Description:
- upravil Tomáš Lenoch and S 255 obrázky v textu
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
338. Host condition effects upon Agrilus planipennis (Coleoptera: Buprestidae) captures on decoy-baited branch traps
- Creator:
- Domingue, Michael J., Berkebile, Jennifer, Steiner, Kim, Hall, Loyal P., Cloonan, Kevin R., Lance, David, and Baker, Thomas C.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, krascovití, polník, fenomenologie, beetles, Buprestidae, Agrilus, phenomenology, Coleoptera, Agrilus planipennis, emerald ash borer, exit hole, flight, invasive species, mate search, 2, and 59
- Language:
- English
- Description:
- We deployed branch traps in an ash (Fraxinus) plantation to investigate how Agrilus planipennis behavior is associated with Fraxinus pennsylvanica condition and dispersal patterns. Data were collected from traps with or without the presence of beetle visual decoys, and from a yearly survey of exit holes. The traps were placed on trees that were either clearly declining, with most foliage arising from epicormic sprouting, or on apparently healthy trees, with little evidence of damage or decline. We calculated correlations of exit holes among neighboring tree rings and also between exit holes and male trap captures. The damaged trees the traps were hung upon had more cumulative exit holes observed than the corresponding healthy trees. However, there was otherwise no evidence that the experiment was biased by differences in exit hole patterns of the surrounding trees. Male captures were greater on decoy-baited traps than controls and this decoy effect was most clearly apparent late in the season when traps were placed on healthy trees. There were also patterns of correlations between male captures and exit hole numbers that may be indicative of short-range mate finding-and dispersal behaviors. Female captures were sparser, but were positively affected by decoys on healthy and declining trees early in the season. Thus, the results suggest that the placement of such traps on healthier trees will maximize detection, and the branch traps also show promise for further use in dispersal studies., Michael J. Domingue, Jennifer Berkebile, Kim Steiner, Loyal P. Hall, Kevin R. Cloonan, David Lance, Thomas C. Baker., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
339. Host plants and aphid hosts influence the selection behaviour of three aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae)
- Creator:
- Albittar, Loulou, Ismail, Mohannad, Bragard, Claude, and Thierry Hance
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, Aphidiinae, Aphididae, aphid, broad bean, host preference, parasitoid, plant influence, sugar beet, 2, and 59
- Language:
- English
- Description:
- Aphis fabae and Myzus persicae (Hemiptera: Aphididae) are insect pests that damage sugar beet and bean crops. Both are responsible for losses in yield and transmission of viral diseases, and may be present on the same host at the same time. Three parasitoid species, Aphidius colemani, Lysiphlebus testaceipes and Lysiphlebus fabarum (Hymenoptera: Braconidae: Aphidiinae) have the potential to be used as biological control agents against at least one of these species of aphids. As a first step prior to the implementation of a biological control program, our aim was to understand the host selection behaviour of the parasitoids, particularly when both aphids are present. We recorded the host acceptance (number of insertions of the ovipositor / number of antennal contacts), suitability (number of mummies / the number of insertions of the ovipositor) and emergence (number of adults emerging from mummies) of these three aphid parasitoids when parasitizing the two aphids. We also analyzed the effect of the host plant on the host preference of the parasitoid. Females of each parasitoid species (n = 15) were exposed to 20 aphids of A. fabae or M. persicae, or a mixture of these two species of aphids, for 15 min, on a leaf disc of each of the two host plants, sugar beet and bean. Higher host acceptance and suitability were recorded for A. colemani attacking both species of aphid: A. fabae (43 and 46%) and M. persicae (43 and 46%) on beet and bean plants respectively, compared to L. testaceipes and L. fabarum. L. testaceipes and L. fabarum showed a clear preference for A. fabae. L. fabarum accepted M. persicae on both plants only when it was mixed with A. fabae, probably due to a confusion effect. We found that the host plant played a significant role in host acceptance, host suitability. We conclude that A. colemani is the better of the three parasitoids studied for the biological control in bean, and particularly, sugar beet crops. and Loulou Albittar, Mohannad Ismail, Claude Bragard, Thierry Hance.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
340. Host-parasite and phylogenetic relationships of Myxobolus filamentum sp. n. (Myxozoa: Myxosporea), a parasite of Brycon orthotaenia (Characiformes: Bryconidae) in Brazil
- Creator:
- Naldoni, Juliana, Zatti, Suellen A, Capodifoglio, Kassia R. H, Milanin, Tiago, Maia, Antônio A. M, Silva, Marcia R. M, and Adriano, Edson A
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- sladkovodní ryby, freshwater fishes, taxonomy, 18S rRNA, ultrastructure, granulocytic cells, Neotropical Region, 2, and 59
- Language:
- English
- Description:
- Myxobolus filamentum sp. n. was found infecting gill filaments of three of 39 Brycon orthotaenia Günther specimens examined (8%), which were taken from the river São Francisco in Minas Gerais state, Brazil. Plasmodia of the parasite were white and long, measuring 5 mm in lenght. Mature spores of M. filamentum sp. n. were oval from the frontal view and biconvex from the lateral view, measuring 7.5-9.7 µm (9.0 ± 0.3 µm) in length and 5.2-7.3 µm (6.2 ± 0.4 µm) in width. The polar capsules were elongated and equal in size, measuring 3.8-5.5 µm (4.7 ± 0.3 µm) in length and 1.3-2.2 µm (1.7 ± 0.1 µm) in width. The development of the parasite led to compression of the adjacent tissues and inflammatory infiltrate with granulocytic cells. Ultrastructural observation revealed that the plasmodia were delimited by two membranes, which had numerous and extensive pinocytotic channels extending into the wide ectoplasm zone. The plasmodial wall exhibited abundant villi-like projections and a thin layer of granular material prevented direct contact between the plasmodial wall and the host tissue. Phylogenetic analysis, based on 18S rDNA, showed M. filamentum sp. n. as a sister species of Myxobolus oliveirai Milanin, Eiras, Arana, Maia, Alves, Silva, Carriero, Ceccarelli et Adriano, 2010, a parasite of other fish species of the genus Brycon Müller et Troschel from South America., Juliana Naldoni, Suellen A. Zatti, Kassia R.H. Capodifoglio, Tiago Milanin, Antônio A.M. Maia, Marcia R.M. Silva, Edson A. Adriano., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public