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122. Contribution to the biochemical characterization of the silk and structure characterization of the cocoons of the horse chestnut leaf miner Cameraria ohridella (Lepidoptera: Gracillariidae)
- Creator:
- Hněvsová, Veronika, Dalibor Kodrík, and František Weyda
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, silk, cocoon, pupal chamber, tissue of leaf mine, Cameraria ohridella, Gracillariidae, protease inhibitor, glycoprotein, electron microscopy, 2, and 59
- Language:
- English
- Description:
- This study of the proteins in the silk of the summer and winter cocoons of the horse chestnut leaf miner Cameraria ohridella revealed they can inhibit protease activity. The inhibitory activity of the summer silk was higher against both the fungal proteinase K and bacterial subtilisin than that of the winter silk. Also, the winter silk was more effective in inhibiting proteinase K than subtilisin. Further, it was demonstrated that some of the silk proteins are glycosylated probably by mannose carbohydrates. An electron microscopy study of the cocoons revealed the presence of silk fibres with different diameters in some pupal chambers. and Veronika Hněvsová, Dalibor Kodrík, František Weyda.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
123. Cooperative defence of brood in Nicrophorus quadripunctatus (Coleoptera: Silphidae)
- Creator:
- Suzuki, Seizi
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Coleoptera, Silphidae, Nicrophorus quadripunctatus, biparental care, defence of carcass, 2, and 59
- Language:
- English
- Description:
- A positive correlation between the parental effort of a male and female should promote stable biparental care. In order to prevent infanticide male and female burying beetles are said to guard against intruders cooperatively and the presence of a male partner is said to increase the probability of successful defence. However, this hypothesis is supported only by indirect evidence. In this study this hypothesis is tested by direct observation. Whether the intruder was male or female, contests between the same and the opposite sex occurred, although there were few contests between resident females and intruding males. In addition, resident pairs tended to win irrespective of the sex of the intruder, although it is reported that among burying beetles large beetles usually win intra-sexual contests. In the presence of a partner, a small resident can defend a carcass against a large con-sexual intruder. These results suggest that by means of biparental cooperation burying beetles can repel stronger intruders and supports the hypothesis that the threat of infanticide is the primary explanation for extended biparental care in these beetles. and Seizi Suzuki.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
124. Correlations between landscape attributes and ecological traits of Lepidoptera communities in olive groves
- Creator:
- Scalercio, Stefano, Brandmayr, Pietro, Iannotta, Nino, Petacchi, Ruggero, and Boccaccio, Luigi
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Landscape ecology, Lepidoptera, biodiversity, ecological traits, conservation, 2, and 59
- Language:
- English
- Description:
- The effects of landscape attributes on Lepidoptera communities were studied in an agricultural area in Calabria (S-Italy). The association between a set of community descriptors and landscape metrics was determined using a multi-scale approach. Lepidoptera were sampled using yellow sticky traps in 10 olive groves. The landscape in 5 concentric areas, with radii from 250 to 1250 m, around each sampling site was analyzed. The composition and configuration of the landscape were calculated both at the landscape and class level based on the main classes of land use. The following life-history traits of Lepidoptera were considered: (i) dispersal ability of adults, (ii) habitat preferences and (iii) diet breadth of larvae. An index of community vulnerability was calculated by combining life-history traits and species diversity. There were no significant correlations between any of the landscape metrics and species richness or between species richness and abundance of natural or semi-natural habitats. However, life-history traits were significantly correlated with some landscape metrics, depending on the spatial scale. Most notably, landscape diversity is positively correlated with community vulnerability. The presence of sensitive species in olive orchards, but not species richness per se, is associated with the presence of natural and semi-natural habitats in the surrounding agricultural landscape. In conclusion, responses of communities to landscape changes are more likely to be revealed by an analysis of ecological traits, than species richness. In particular, the vulnerability index, used in this joint analysis of the main ecological traits, seems to be an effective descriptor of the relationships between communities and landscape., Stefano Scalercio ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
125. Cost to the cavity-nest ant Temnothorax crassispinus (Hymenoptera: Formicidae) of overwintering aboveground
- Creator:
- Mitrus, Slawomir
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Formicidae, Temnothorax crassispinus, percentage survival, overwintering, 2, and 59
- Language:
- English
- Description:
- Most species of ants inhabiting the temperate zone overwinter underground, whereas those of the genus Temnothorax remain in nests aboveground. I studied the cost of aboveground overwintering. Workers of Temnothorax crassispinus survived in higher numbers (median = 88%) in artificial nests experimentally buried at a depth of 5 cm than those in nests on the surface (48%) of the soil. The results support the hypothesis that overwintering aboveground could be a consequence of a limited supply of nests and/or the advantage of being able to respond quickly to warm temperatures in spring. Address, Slawomir Mitrus., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
126. Costanera Sur - za zvířaty v argentinském velkoměstě
- Creator:
- Andrej Funk and Funková, Kateřina
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, národní parky, ptáci, savci, životní prostředí, ekologie, national parks, birds, mammals, environment, ecology, 2, and 59
- Language:
- Czech
- Description:
- The Costanera Sur ecological reserve in Buenos Aires, Argentina, was established in 1986 on the banks of the Rio de la Plata on excavated substrata landfill, where free space was left for plant and animal communities to take over. The 350 ha of the reserve include such biotopes as wetlands, pampas and small areas of woodland, providing a valuable site for the city's inhabitants to meet various species of animals in close proximity to the historical city centre, e.g. 270 bird species have been recorded there., Andrej Funk, Kateřina Funková., Ekologická rezervace Costanera Sur v Buenos Aires v Argentině vznikla v roce 1986 na břehu Río de La Plata na skládce vytěženého substrátu, kde byl ponechán volný prostor k sukcesi společenstev rostlin a živočichů. Na ploše 350 ha rezervace zahrnuje biotopy mokřadů, pampy a malých úseků lesa a představuje cennou lokalitu pro rekreaci obyvatel města i pro poznávání různých druhů zvířat v těsné blízkosti historického centra města. Zatím zde byl doložen výskyt např. 270 druhů ptáků., and cze
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
127. Cream and albinotic - two new mutations affecting body colour in Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)
- Creator:
- Radomír Socha
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, firebug, body-colour mutants, albinotic, cream, inheritance pattern, reproductive potential, 2, and 59
- Language:
- English
- Description:
- Two new body-colour mutations, albinotic (alb) and cream (cr) are isolated and described for the flightless wing-polymorphic bug, Pyrrhocoris apterus (L.). The body colour of alb mutants is white and that of cr mutants either a light cream or creamy yellow. Both the alb and cr mutations most probably inhibit the biosynthesis of the red pigment in epidermal cells that is responsible for the red-coloured body of wild-type bugs. Although sometimes the body colour of younger larval instars of cr mutants is a slightly darker creamy yellow and that of last larval instars of the alb mutants a slightly whiter greyish, there were no other important developmental changes in the body colour of alb and cr homozygous bugs associated with metamorphosis and post-metamorphic aging of adults. Standard genetic analyses showed that both these mutations are inherited as autosomal recessives and exhibit complete penetrance and uniform expression in both sexes. The fertility of the alb and cr homozygous females and fertilization success of the alb and cr homozygous males were substantially lower than those of wild-type bugs. and Radomír SOCHA.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
128. Cryoprotectant systems and cold tolerance of insects inhabiting central Yakutia (Russian Far East)
- Creator:
- Li, Natalia G.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, glycerol, hmyz, insects, freeze-tolerance, ice nucleators, cold hardiness potential, Siberian insects, 2, and 59
- Language:
- English
- Description:
- Strong tolerance of freezing is an important strategy for insects living in extremely cold regions. They produce highly effective cryoprotectant systems consisting of ice-nucleating proteins and polyols, which enables tolerable freezing of the body fluid. Therefore, the measurement of the concentrations of polyols and the activity of ice nucleators in the haemolymph is an essential tool for describing tolerance to ice formation in insects occurring in particularly cold places. This study evaluates three parameters: insect body supercooling point (SCP), haemolymph glycerol content and the profile of haemolymph ice nucleating activity that characterize the strategies of cold adaptation and cold hardiness in two previously unstudied beetles, Chrysolina graminis graminis L. and Galerucella nymphaea L., inhabiting Yakutia (Russian Far East, latitude 62°N). The high SCP values, ice nucleating activity and survival of the chrysomelids after freezing indicate that both species are tolerant of freezing. According to the profiles of ice-nucleating activity, the haemolymph from C. graminis graminis is characterized by a higher nucleating potential than that from G. nymphaea. The glycerol level is also higher in C. graminis graminis. The results indicate that both species develop tolerance to low temperatures, but the cold hardiness potential of C. graminis graminis is greater than that of G. nymphaea. This was revealed by the survival test, in which beetles were frozen to a temperature of -22°C for 30 min; 86% of C. graminis graminis and 72% of G. nymphaea survived the test. Thus, the freeze-tolerance of these beetles seems to be based on the production of an integrated cryoprotectant system, the quality of which apparently influences the range of their cold resistance., Natalia G. Li., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
129. Čtvrtstoletí průzkumu vážek na Podblanicku
- Creator:
- Lubomír Hanel
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, entomologie, vážky, entomology, Odonata, Podblanicko (Česko), Podblanicko (Czechia), 2, and 59
- Language:
- Czech
- Description:
- Lubomír Hanel.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
130. Cytogenetic characterization of Diachasmimorpha longicaudata (Hymenoptera: Braconidae), a parasitoid wasp used as a biological control agent
- Creator:
- Carabajal Paladino, Leonela, Papeschi, Alba, Lanzavecchia, Silvia, Cladera, Jorge, and Bressa, María José
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Braconidae, Diachasmimorpha longicaudata, karyotype, C-banding, heterochromatin, Ag-NOR, FISH, rDNA, 2, and 59
- Language:
- English
- Description:
- Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is a parasitoid wasp widely used in the biological control of fruit flies. In this paper, we present a detailed analysis of the karyotype of this species based on the results of classical and molecular cytogenetic techniques. The cytogenetic analysis confirmed the male and female chromosome numbers previously reported (n = 20, 2n = 40). The entire short arm of most chromosomes is made up of a large constitutive heterochromatic segment. The high heterochromatin content differentiates D. longicaudata from other braconid species. Fluorescence in situ hybridization (FISH) using autologous 18S rDNA probes revealed six clusters of rDNA, i.e. six nucleolar organizer regions (NORs), in the heterochromatic short arms of different chromosomes in the haploid male karyotype. This number is exceptionally high for Hymenoptera, which usually have two NORs in the diploid complement. It is noteworthy that these rDNA-FISH experiments represent the first use of this technique on a braconid species using autologous probes. Since Ag-NOR-bands were coincident with C-positive bands on metaphase chromosomes, it was not possible to identify active nucleoli. The physical characteristics of the D. longicaudata karyotype, especially the content and distribution of heterochromatin and the number and location of rDNA clusters, contribute to a better understanding of the structure and organization of braconid chromosomes and provide a basis for genomic and evolutionary studies., Leonela Carabajal Paladino ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public