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32. 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
33. 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
34. 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
35. 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
36. 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
37. 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
38. 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
39. Implications of insect responses to supernormal visual releasing stimuli in intersexual communication and flower-visiting behaviour: a review
- Creator:
- Kral, Karl
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, hmyz, motýli, čmelák, opylovači, insects, butterflies, bumble bees, pollinators, visual stimuli, mating, foraging, orchid mimicry, food reward, floral size, floral symmetry, ultraviolet signals, 2, and 59
- Language:
- English
- Description:
- Animals, including human beings, tend to respond more strongly to stimuli that are associated with the highest relative rewards. This applies not only to food rewards but also to reproductive success. In the present review article this issue is discussed for insects in connection with intersexual communication and flower-visiting behaviour. Implications of the preference for supernormal visual releasing stimuli are examined from a sensory and evolutionary perspective, including a consideration of the choice of potential mates and recognition of the most rewarding flowers., Karl Kral., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
40. Insect cold tolerance: How many kinds of frozen?
- Creator:
- Sinclair, Brent J.
- 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, tolerance k chladu, tolerance k mrazu, netolerance k mrazu, teplotní strategie, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- Insect cold tolerance mechanisms are often divided into freezing tolerance and freeze intolerance. This division has been criticised in recent years; Bale (1996) established five categories of cold tolerance. In Bale's view, freezing tolerance is at the extreme end of the spectrum of cold tolerance, and represents insects which are most able to survive low temperatures. Data in the literature from 53 species of freezing tolerant insects suggest that the freezing tolerance strategies of these species are divisible into four groups according to supercooling point (SCP) and lower lethal temperature (LLT): (1) Partially Freezing Tolerant-species that survive a small proportion of their body water converted into ice, (2) Moderately Freezing Tolerant-species die less than ten degrees below their SCP, (3) Strongly Freezing Tolerant-insects with LLTs 20 degrees or more below their SCP, and (4) Freezing Tolerant Species with Low Supercooling Points which freeze at very low temperatures, and can survive a few degrees below their SCP. The last 3 groups can survive the conversion of body water into ice to an equilibrium at sub-lethal environmental temperatures. Statistical analyses of these groups are presented in this paper. However, the data set is small and biased, and there are many other aspects of freezing tolerance, for example proportion of body water frozen, and site of ice nucleation, so these categories may have to be revised in the future. It is concluded that freezing tolerance is not part of Bale's (1996) continuum, but rather a parallel, alternative strategy of cold tolerance., Brent J. Sinclair, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public