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172. 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
173. Cytogenetic variability among Bradyporinae species (Orthoptera: Tettigoniidae)
- Creator:
- Warchalowska-Sliwa, Elzbieta, Grzywacz, Beata, Maryanska-Nadachowska, Anna, Karamysheva, Tatyana V., Chobanov, Dragan P., and Heller, Klaus-Gerhard
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Orthoptera, Ephippigerini, Bradyporini, karyotype evolution, chromosome fusion, B chromosomes, FISH, rDNA, 2, and 59
- Language:
- English
- Description:
- 1_Chromosomes of six European species (one with two subspecies) of Orthoptera belonging to the tribes Ephippigerini and Bradyporini were analyzed using C-banding, Ag-NOR, DAPI (AT-rich)/CMA3 (GC-rich) staining and fluorescence in situ hybridization (FISH) using the 18S rDNA and (TTAGG)n telomeric probes with the aim to better understand chromosomal organization and evolutionary relationships between genera and subgenera within and across both tribes. The evolution of karyotypes was studied in terms of changes in chromosome number (2n) and morphology (FN, the fundamental number – i.e. the number of chromosome arms including the X chromosome). The ancestral 2n = 31 was reduced to 2n = 29 (FN = 31) and 27 (FN = 31) by one or two Robertsonian fusions in the Ephippigerini. Whereas in the Bradyporini 2n = 27 (FN = 32) as a result of two Robertsonian translocations and a pericentric inversion in the X chromosome. The quantity of heterochromatin in GC-rich regions distinguished the karyotypes of Ephippigerini (only a single CG-rich band on one autosome pair) from those of Bradyporini (CG-rich bands on all chromosomes). FISH using the 18S rDNA probe localized 1–3 rDNA clusters to autosomes and/or to the X chromosome in all species examined. The rDNA loci coincided with active NORs as determined by Ag-NOR staining. A comparison of the location of the single NOR/rDNA in two species of the genus Steropleurus (Ephippigerini) suggests that the reduced chromosome number in S. pseudolus results from a Robertsonian fusion between two pairs of autosomes, one of them carrying the NOR/rDNA as in S. stalii (and also in E. ephippiger)., 2_Whereas the karyotypes of three species of the genus Bradyporus, though showing the same chromosome number and morphology, differed in the number and distribution of NORs/rDNA sites [one autosomal in B. (B.) dasypus versus three in B. macrogaster and B. (C.) oniscus, two of them X-linked]. Trends in karyotype diversification of the taxa based on the present data and previous research are discussed. In some individuals belonging to the species Bradyporus (B.) dasypus and B. (C.) m. macrogaster B chromosomes (Bs) were detected: acrocentric (the smallest elements in the complement) and submetacentric (similar to medium-sized autosomes), respectively., Elzbieta Warchalowska-Sliwa ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
174. Daily survival and dispersal of adult Rhagonycha fulva (Coleoptera: Cantharidae) in a wooded agricultural landscape I
- Creator:
- Rodwell, Laura E, Day, Jennifer J, Foster, Christopher W, and Holloway, Graham J
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- brouci, dlouhověkost, beetles, longevity, Cantharidae, Rhagonycha fulva, Hogweed bonking beetle, soldier beetle, mark re-sighting, movement, settling, landscape connectivity, landscape configuration, 2, and 59
- Language:
- English
- Description:
- Studies of insect population under field conditions to establish survival rates, longevity and dispersal rates are rare in the literature. These types of studies are important and can be used to inform studies of the effects of landscape composition and configuration on levels of biodiversity. Here the Cantharidae beetle, Rhagonycha fulva is studied under field conditions to derive estimates of daily survival rates for both males and females as well as local dispersal rates. Survival was studied at two sites, one in Wales and another in England, whilst dispersal was examined only at the Welsh site. Beetles were marked using different coloured enamel paints at the mid-point of a 200 m linear transect. The beetles were almost exclusively found (and marked) on common hogweed, Heracleum sphondylium. No difference in survival was found between males and females at both of the sites. The survival rates found at the two sites also did not differ. The overall daily survival rate was 0.771 equating with a median longevity of 4.37 days. Casual observations yielded a small number of marked individuals in excess of 400 m away from the point of marking. Movement of males along the transect differed from females. Marked females were never found far from the point of marking whilst males moved further away with time. This difference in behaviour is discussed in terms of hypothesized insect dispersal behaviour following emergence as mobile adults., Laura E. Rodwell, Jennifer J. Day, Christopher W. Foster, Graham J. Holloway., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
175. Damselflies (Zygoptera) as paratenic hosts for Serpinema trispinosum and its report from turtle hosts from Oklahoma, USA
- Creator:
- Wiles, Crystal M and Bolek, Matthew G
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- hlístice, želvy, morfologie (biologie), Nematodes, turtles, morphology (biology), damselflies, paratenic hosts, 2, and 59
- Language:
- English
- Description:
- Third-stage larvae of the nematode Serpinema trispinosum (Leidy, 1852) were collected from the midgut of four of five species of adult damselflies (Zygoptera) from a non-irrigated restored semipermanent wetland located in Stillwater, Oklahoma, USA. Of the four infected damselfly species, prevalence and mean abundance was highest for the southern spreadwing, Lestes disjunctus australis Walker (10%, 0.2 ± 0.8) and lowest for the familiar bluet, Enallagma civile (Hagen) (2.5%, 0.04 ± 0.3); whereas mean intensities were lowest for the citrine forktail, Ischnura hastata (Say) (1.5 ± 0.5) and the eastern forktail, Ischnura verticalis (Say) (1.0 ± 0). This is the first record of larvae of S. trispinosum from damselflies. Serpinema trispinosum adults have been reported from 18 species of North and Central American freshwater turtles, whereas microcrustaceans such as copepods serve as intermediate hosts and snails, fish and amphibians serve as paratenic hosts in this nematode's life cycle. However, dietary studies of the 18 species of freshwater turtles reported as definitive hosts for S. trispinosum indicate that aquatic insects including damselflies are more commonly reported in turtle diets than are fish or amphibians. Additionally, unlike snails and amphibians, larval damselflies predominantly feed on microcrustaceans, and our observation of S. trispinosum infecting damselflies may reflect the importance of these insects as paratenic hosts. In the present study, we provide new host information and measurements for third-stage larvae of S. trispinosum from damselfly hosts along with measurements for adult male and female S. trispinosum from turtle hosts from Oklahoma, USA., Crystal M. Wiles, Matthew G. Bolek., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
176. Dan Bárta, Aleš Dolný: Vážky Sungai Wainu. Dragonflies of Sungai Wain. Capung-Capung Sungai Wain
- Creator:
- Lubomír Hanel
- Type:
- article, recenze, recensions, model:article, and TEXT
- Subject:
- Zoologie, zoologie, 2, and 59
- Language:
- Czech
- Description:
- [autor recenze] Lubomír Hanel.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
177. Darrell Huff: Jak lhát se statistikou
- Creator:
- Pavel Kovář
- Type:
- article, recenze, recensions, model:article, and TEXT
- Subject:
- Zoologie, statistika, 2, and 59
- Language:
- Czech
- Description:
- [autor recenze] Pavel Kovář.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
178. Demography of adults of the Marsh fritillary butterfly, Euphydryas aurinia (Lepidoptera: Nymphalidae) in the Czech Republic: Patterns across sites and seasons
- Creator:
- Kamil Zimmermann, Blažková, Pavla, Čížek, Oldřich, Frič, Zdeněk, Hůla, Vladimír, Kepka, Pavel, Novotný, David, Slámová, Irena, and Martin Konvička
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Česko, Czechia, Lepidoptera, Nymphalidae, Euphydryas aurinia, Marsh fritillary, butterfly conservation, demography, density dependence, grasslands, local dynamics, metapopulation, 2, and 59
- Language:
- English
- Description:
- The Marsh fritillary (Euphydryas aurinia) (Lepidoptera: Nymphalidae) has declined across Europe, including the Czech Republic. Current conservation strategies rely on prevention of habitat loss and degradation, and increase in habitat quality and connectivity via promoting traditional grassland management. The population structure and adult demography parameters of a single population was investigated for eight years (single system), and of all the known Czech populations (multiple populations) for a single year, using mark-recapture. There was substantial variation in the patterns of adult demography, both among years in the single system and among the multiple populations in a single year. In the single system, the date of the first flight of an adult varied by 18 days over the 8 years and total annual numbers varied with a coefficient of variation of 0.40 (females fluctuating more than males). The average density was ca 80 adults/ha. The population size displayed density-dependence, i.e. decreased following years with high adult numbers, with an equilibrium density of 90 individuals/ha. The average density of the multiple populations was ca 120 individuals/ha. The estimated total population for the Czech Republic was 25,000 individuals (17,000 males / 8,000 females) in 2007, which does not indicate an imminent threat of extinction. The regional persistence of E. aurinia is likely to depend on re-colonisation of temporarily vacant sites by dispersing individuals, facilitated by local shifts in adult flight phenology to that better adapted to local conditions. and Kamil Zimmermann, Pavla Blazkova, Oldrich Cizek, Zdenek Fric, Vladimir Hula, Pavel Kepka, David Novotny, Irena Slamova, Martin Konvicka.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
179. Demography of the endangered butterfly Euphydryas aurinia (Lepidoptera: Nymphalidae): A case study of populations in sub-Mediterranean dry calcareous grasslands
- Creator:
- Jugovic, Jure, Uboni, Costanza, Zupan, Sara, and Lužnik, Martina
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- motýli, babočkovití, demografie, grasslands, butterflies, Nymphalidae, demography, Slovinsko, Slovenia, Euphydryas aurinia, mark-release-recapture, movement, nectar plants, metapopulation, 2, and 59
- Language:
- English
- Description:
- We studied a population of the regionally endangered marsh fritillary butterfly Euphydryas aurinia inhabiting a system of loosely connected dry calcareous grasslands in sub-Mediterranean Slovenia. Our goal was to set the basis for a long-term monitoring of this butterfly in four meadows using mark-release-recapture (MRR). We determined its demographic parameters, dispersal, behaviour and utilization of nectar plants in different quality patches. Total population size was estimated to be approximately 347 males (95% confidence interval: 262-432) and 326 females (95% confidence interval: 250-402), with an unbiased sex ratio. The average lifespans were 6.3 and 8.6 days, respectively. Daily population sizes followed a parabola with marked protandry. Both sexes were relatively highly mobile with both occasionally moving over half a kilometre. The spatial distribution of animals seemed to be associated with patch size, host plant densities and nectar sources, resulting in much higher population densities in the largest patch. Adult behaviour differed between the sexes, with females resting more and flying less than males. Behaviour also changed during daytime and with the progression of the season. Adults were confirmed to be opportunistic feeders, since as many as ten nectar sources were detected. We conclude that demographic parameters differ greatly among regions and habitats, thus conservation aims should be planned accordingly. Although the population studied is apparently in good condition, there are threats that may hamper the long-term persistence of the species in this area: succession, intensification of mowing and overgrazing., Jure Jugovic, Costanza Uboni, Sara Zupan, Martina Lužnik., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
180. Density-invariant dispersion indices and fixed precision sequential sampling plans for the peach twig borer Anarsia lineatella (Lepidoptera: Gelechiidae)
- Creator:
- Damos, Petros
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- motýli, makadlovkovití, vzorkování, butterflies, Gelechiidae, sampling, Anarsia lineatella, spatial dispersion, integrated pest management, moth, peach production, 2, and 59
- Language:
- English
- Description:
- Estimating the spatial dispersion of pest arthropods is crucial for the development of reliable sampling programs and one of the main components of integrated pest management. The natural spatial distribution of a population of a species may be random, uniform, or aggregated and can be so classified based on calculation of variance to mean relations and related dispersion indices. In this work some classical density-invariant dispersion indices and related regression models are used for the first time to quantify the spatial dispersion of an important peach pest Anarsia lineatella Zeller (Lepidoptera: Gelechiidae) and construct fixed precision sequential sampling schemes. Taylor's power law, Iwao's patchiness regression and Nachman's model were used to analyse the damage to peaches caused by A. lineatella. All three regression models fit the data well, although the results indicate that Iwao's patchiness model provides a better description of the relationship between variance and mean density. Taylor's b and Iwao's b regression indices were both significantly smaller than 1, indicating that the distribution of individuals was uniform rather than random or aggregated. According to Green's and Kuno's models, the minimum sample size at the precision level of 0.2 varies from 3 samples, when total population density is more than 3 larvae/sample, to 10 samples, when population density is between 1 and 2 larvae/sample. Kuno's fixed sampling plan indicates that a small number of samples (i.e., 3-10 branches with fruit) is sufficient to estimate the mean population density of A. lineatella larvae with a precision of 0.2. The Resampling for validation of sampling plans (RVSP) method confirmed that the average level of precision of the fixed sequential plans matched the desired precision in most cases. The sampling plan presented here provides a level understanding of A. lineatella spatial ecology suitable for pest manage, Petros Damos., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public