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132. 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
133. 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
134. 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
135. 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
136. 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
137. Host spatial pattern influences induction of parasitization by Trichogramma (Hymenoptera: Trichogrammatidae)
- Creator:
- Voinovich, Nataliya D., Umarova, Taisiya Ya., and Sergey Ya.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, blanokřídlí, Trichogrammatidae, Trichogramma principium, samičky, parasitizmus, Sitotroga cerealella (hostitel), vajíčka hostitele, uspořádání vajíček, vztahy, 591.5, 576, and 595.2/.7
- Language:
- English
- Description:
- The influence of host intrapatch spatial distribution on parasitoid host acceptance behavior was investigated with Trichogramma principium parasitizing eggs of grain moth, Sitotroga cerealella. Single females were placed in Petri dishes, each containing 60 host eggs arranged either as a compact patch or partitioned into 60 or 12 clusters each consisting of 1 or 5 eggs, respectively. Partitioned patches provoked parasitization more often than compact patches. The percentage of ovipositing females (i.e., females parasitizing at least one of 60 host eggs) increased with the number of clusters, while it was independent of the intercluster distance over intervals of 2.5-15 mm. The mean number of eggs parasitized by ovipositing females during 48 h was almost independent of the host egg spatial pattern. As a result, the rate of parasitization was higher when the hosts were sparsely distributed within a patch than when they were aggregated., Nataliya D. Voinovich, Taisiya Ya. Umarova, Sergey Ya. Reznik, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
138. Host-plant mediated influences on population development of Sitobion avenae (Sternorrhyncha: Aphididae)
- Creator:
- Alois Honěk and Martinková, Zdenka
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Aphididae, Sitobion avenae, vývoj populace, hostitelské rostliny, obilniny, ozimá pšenice, vliv kultivaru, vliv hustoty porostu, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- We investigated the effects of genetic differences and host plant density on population development of the rose-grain aphid Sitobion avenae (F.) (Sternorrhyncha: Aphididae) in winter wheat stands. Aphid numbers on ears were recorded on 11 cultivars (6 years) and on plots where crop density was varied by thinning (12 years). Crop density significantly affected whole plant, tiller and ear mass, number of tillers, and leaf area and chlorophyll content. The duration and rate of aphid population growth, and the maximum numbers of aphids were ascertained by weekly counts. Maximum abundances increased with the length of time available for the growth of aphid populations while the rate of population growth was less important. Variation of maximum numbers of S. avenae on different cultivars was not significant, probably due to the small variation in the period available for the development of aphid populations. By contrast, there was a significant Variation of aphid performance associated with host plant density. Aphid populations on solitary plants persisted longer and became more abundant than in dense stands. The prolonged survival of aphid populations was probably caused by an extended period of tillering and lower average age of tillers of solitary plants. There was large annual variation in aphid abundance. It is likely that modifications of host plant development caused by differences in winter weather may contribute to this variation., Alois Honěk, Zdenka Martinková, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
139. How fine is fine-scale? Questioning the use of fine-scale bioclimatic data in species distribution models used for forecasting abundance patterns in butterflies
- Creator:
- Filz, Katharina J., Schmitt, Thomas, and Engler, Jan O.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Invertebrates, spatial abundance, environmental suitability, environmental niche model, MAXENT, 2, and 59
- Language:
- English
- Description:
- The use of species distribution models (SDMs) to predict the spatial occurrence and abundance of species in relation to environmental predictors has been debated in terms of species’ ecology and biogeography. The predictive power of these models is well recognized for vertebrates, but has not yet been tested for invertebrates. In this study, we aim to assess the use of SDMs for predicting local abundances of invertebrates at a macroscale level. A maximum entropy algorithm was used to build SDMs based on occurrence records of 61 species of butterflies and bioclimatic information with a 30 arc second resolution. Predictions of habitat suitability were correlated with butterfly abundance data derived from independently conducted field surveys in order to check for a relationship between the predictions of the model and local abundances. Even though the model accurately described the current distributions of the species in the study area at a macroscale, the observed occurrences of the species (i.e. presence/absence) recorded by the field surveys differed significantly from the model’s predictions for the corresponding grid cells. Moreover, there was no correlation between observed abundance and the model’s predictions for most species of butterflies. We conclude that the spatial abundance of butterflies cannot be predicted from environmental suitability modelled at a resolution as large as in this study. Using the finest scale bioclimatic information currently available (i.e. 30 arc seconds) it is not adequate to predict species abundances as structural and ecological factors as well as climatic patterns acting at a smaller scale are key determinants of the occurrence and abundance of invertebrates. Therefore, future studies have to account for the role of the resolution in environmental predictors when assessments of spatial abundances via SDMs will be conducted., Katharina J. Filz, Thomas Schmitt, Jan O. Engler., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
140. How much care does a shrub-feeding hairstreak butterfly, Satyrium spini (Lepidoptera: Lycaenidae), need in calcareous grasslands?
- Creator:
- Löffler, Franz, Stuhldreher, Gregor, and Fartmann, Thomas
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Lycaenidae, Satyrium spini, clear-cut, conservation management, egg-laying, microclimate, oviposition preference, Rhamnus cathartica, 2, and 59
- Language:
- English
- Description:
- 1_Many butterfly target species are associated with early successional stages of grasslands. The Blue-spot Hairstreak, Satyrium spini (Denis & Schiffermüller, 1775), is a target species of grasslands. However, it feeds on Common Buckthorn (Rhamnus cathartica), which is associated with late successional stages of grasslands. If S. spini would also be restricted to late seral stages, there might be a management dilemma due to the contrasting requirements of S. spini and other target species. The aim of this study was to determine the oviposition preference of S. spini in calcareous grasslands, and to give management recommendations to promote this species. Therefore, we studied the oviposition microhabitats of S. spini at three representative patches of the Diemel Valley (Central Germany) by comparing environmental conditions on occupied and control host plants. In total we surveyed 1,889 host plants. Altogether we found 148 batches of S.spini on them containing 396 eggs. Most of the eggs were on plants that grew under the warmest conditions. Females preferred to lay eggs on small (< 1.3 m) shrubs of Rh. cathartica fully exposed to the sun growing on steep south- and west-facing slopes., 2_This butterfly showed no difference in its preference for bushes growing in hedges or solitarily. About 80% of the batches of eggs were laid on the upper surface of a twig fork close to the surface of the ground (< 1 m). Our study showed that S. spini is a species characteristic of mid-successional stages of calcareous grasslands. The survival of suitable habitats for S. spini depends on regular management. To achieve this we recommend traditional rough grazing with sheep and goats, which creates open grasslands with small Rhamnus plants. In addition, the shrubs in tall hedges bordering calcareous grasslands should be subjected to cutting on a rotating basis., Franz Löffler, Gregor Stuhldreher, Thomas Fartmann., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public