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32. 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

34. 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

35. 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

36. Hrobaříci - důležitá součást přírody

Creator:
Jan Schneider
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, hmyz, mrchožroutovití, insects, Silphidae, 2, and 59
Language:
Czech
Description:
Hrobaříci jsou malá skupina brouků patřící do čeledi mrchožroutovití (Silphidae), která má na světě okolo 190 druhů. Centrem jejich rozšíření je palearktická oblast. Mezi hrobaříky ale najdeme jak zástupce s rozsáhlým areálem výskytu, tak i druhy endemické. Tito brouci žijí na různých biotopech, ale jsou si vzhledově podobní. Vyvinula se u nich naprosto jedinečná péče o potomstvo, kdy se dospělci starají o své larvy. Ze způsobu života hrobaříků a vzájemných potravních vztahů tak přímo vyplývá význam a užitečnost těchto brouků. Odklízením mršin a urychlováním rozkladných procesů jsou velmi prospěšní., Burying beetles are a small group of beetles, belonging to the carrion beetle family (Silphidae), which has around 190 species worldwide. The centre of their distribution is the Palearctic region. While some species are widely distributed, others are endemics with narrow distribution range. Burying beetles live in different habitats, but they are phenotypically similar. They also have developed unique care for offspring when adults care for their larvae. Their necrophore way of life and mutual food relationships directly highlight the importance and usefulness of these beetles. The major ecological importance of burying beetles lies in the removal of carcasses and acceleration of degradation processes., and Jan Schneider.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

37. Hybridisation between Aphis grossulariae and Aphis schneideri (Sternorrhyncha: Aphididae): An experimental approach

Creator:
Rakauskas, Rimantas
Format:
print, text, and regular print
Type:
article, bibliography, model:article, and TEXT
Subject:
zoologie, entomologie, hmyz, Sternorrhyncha, Aphididae, Aphis grossulariae, Aphis schneideri, hybridizace, laboratorní pokusy, 595.2/.7, and 591.1
Language:
English
Description:
A. schneideri and A. grossulariae clones from southern Poland produced fertile hybrid eggs under experimental conditions. Established hybrid clones expressed normal parthenogenetic reproduction but bisexual generations were not obtained, though a few sexuales developed in some cases. Morphological features of A. schneideri and host-specificity of A. grossulariae tended to dominate in the majority of hybrid clones. Independent inheritance of the studied morphological characters and host specificity can therefore be presumed. Present results do not exclude the possibility of natural hybridisation of studied aphid species. Natural crosses might cause taxonomic and currant pest management problems., Rimantas Rakauskas, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

38. Immunocytochemical distribution of angiotensin-I converting enzyme in the central nervous system of insects and speculations about its possible function

Creator:
De Loof, Arnold, Isaac, , Elwyn, Salzet, Michel, Huybrechts, Roger, Veelaert, Dirk, Schoofs, Liliane, Macours, Nathalie, and Vandingenen, Anick
Format:
print, text, and regular print
Type:
article, bibliography, model:article, and TEXT
Subject:
zoologie, entomologie, hmyz, Locusta migratoria, corpus cardiacum, pars intercerebralis, neuropeptidy, angiotensin-I převodní enzym, funkce, rozšíření, imunocytochemické stanovení, 595.2/.7, and 591.1
Language:
English
Description:
Insect peptidyl-dipeptidase A [angiotensin I - converting enzyme (ACE)] is a soluble single-domain peptidyl-dipeptidase that has many properties in common with the C-domain of mammalian somatic ACE and with the single-domain mammalian ACE. In agreement with a variety of insects, immunocytochemical studies reveal the presence of an ACE-like protein in Locusta migratoria. ACE-like immunoreactivity is present in neurosecretory cells of the pars intercerebralis. These cells have axons projecting into the nervus corporis cardiaci I and into the storage part of the corpus cardiacum, a neuroendocrine organ directly releasing into the aorta. The localisation of ACE in neurosecretory cells is consistent with its proposed role as a processing enzyme that is involved in the generation of active peptide hormones., Dirk Veelaert, Liliane Scoofs, Nathalie Macours, Anick Vandingenen, Arnold De Loof, Elwyn Isaac, Michel Salzet, Roger Huybrechts, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

39. Immunolocalization of two types of allatostatins in the central nervous system of the cricket Gryllus bimaculatus (Ensifera: Gryllidae)

Creator:
Witek, Günther, Verhaert, Peter, Lorenz, Matthias W., and Hoffmann, Klaus H.
Format:
print, text, and regular print
Type:
article, bibliography, model:article, and TEXT
Subject:
zoologie, fyziologie živočichů, hmyz, Gryllidae, Gryllus bimaculatus, centrální nervový systém, neuropeptidy, allatostatiny, lokalizace, stanovení, imunocytochemické metody, 595.2/.7, and 591.1
Language:
English
Description:
Two anti-peptide antisera (anti-A and anti-B) raised against Gryllus bimaculatus allatostatin A1 (Grb-AST A1) and B1 (Grb-AST B1), respectively, were applied in the peroxidase-antiperoxidase (PAP) immunohistochemical technique on complete series of sections from the brain, suboesophageal ganglion, corpora cardiaca (CC), and corpora allata (CA) of G. bimaculatus. Both antisera yielded intense staining of numerous cells and nerve fibres. Serial sections, alternately stained with anti-A and anti-B confirmed that the anti-B generally stained more cells and nerves. Extensive immunoreactivity in the retrocerebral complex suggests that the CC and CA may represent a storage and/or release site for both allatostatin types or allatostatin-like molecules produced in the brain., Günther Witek, Peter Verhaert, Matthias W. Lorenz, Klaus H. Hoffmann, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

40. Impacts and responses at population level of herbivorous insects to elevated CO2

Creator:
Whittaker, John B.
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, herbivorní hmyz, populace, životní cyklus, klimatické změny, oxid uhličitý, vliv CO2, 591.5, 061.3, and 595.2/.7
Language:
English
Description:
Most studies of responses of insects to elevated carbon dioxide have been made using short-term exposures to treated food plants and have involved measurements of responses in growth, reproduction, food consumption and efficiencies of conversion at specific stages in the life cycle. These will be reviewed in the light of longer-term studies recently published where whole generations have been reared in chambers with simultaneous treatment of plants and where insects have been free to select their food and microenvironment. Factors such as seasonal change in plants, choice of food plant, mode of feeding, timing of exposure, temperature, the role of natural enemies are considered and the whole placed in the context of other aspects of climate change. It is concluded that in studies to date, the only feeding guild in which some species have shown increases in population density in elevated carbon dioxide are the phloem feeders. Chewing insects (both free-living,and mining) generally have shown no change or reduction in abundance, though relative abundance may be greatly affected. Compensatory feeding is common in these groups., John B. Whittaker, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public