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2. Altitudinal gradient in species richness and composition of dung beetles (Coleoptera: Scarabaeidae) in an eastern Euro-Mediterranean locality: functional, seasonal and habitat influences
- Creator:
- Şenyüz, Yakup , Lobo, Jorge M., and Dindar, Kemal
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Scarabaeidae, Aphodiinae, dung beetles, species richness, historical factors, elevational turnover, seasonal variation, habitat, and Anatolia
- Language:
- English
- Description:
- The altitudinal gradient in diversity of dung beetles (Scarabaeidae) was studied in a Mediterranean mountain chain located in Central Anatolia to (i) determine if there are altitudinal differences between the main taxonomic groups, (ii) describe the seasonal variations in these assemblages and (iii) assess whether closed habitats influence dung beetle diversity differentially at different altitudes. Beetles were collected throughout a year at 14 localities between 469 and 1810 m above sea level in three different types of habitats. Dung beetle assemblages at 400 to 1200 m did not vary greatly in species richness, abundance and biomass. However, they varied in composition, with the assemblages dominated by species of Scarabaeinae up to 900 m, whereas in the mid-mountain assemblages (from 900 m to 1600 m) the numbers of species of Aphodiinae was higher. The decline with increase in altitude in richness, abundance and biomass of both small and large species of Scarabaeinae up to 1500 m, together with the constancy of these parameters in the case of Aphodiinae, accounts for the changes in the composition from the lowland to mid-mountain localities. Unlike at other Mediterranean localities, the open/closed structure of the habitat only slightly influences these assemblages independently of altitude or season. The general seasonal pattern follows the classical Mediterranean bimodal pattern associated with summer drought, but the patterns are more complex when the seasonal responses of the different groups and at different localities are analysed separately. We propose that the interplay between local climatic conditions (mainly temperature) and evolutionary conserved species preferences accounts for both the current seasonal and altitudinal gradients and the changes in species composition in terms of Aphodiinae and Scarabaeinae.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Burial-induced changes in the seed preferences of carabid beetles (Coleoptera: Carabidae)
- Creator:
- Saska, Pavel, Honěk, Alois, Foffová, Hana, and Martinková, Zdenka
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Carabidae, food preferences, granivory, seed consumption, seed burial, and weeds
- Language:
- English
- Description:
- Seeds of many species of plants may survive for a long time in the soil and germinate when brought to the surface, but whether they are subsequently eaten by seed predators is unknown. We examined the preferences of three species of carabids (Coleoptera: Carabidae) for 25 species of seeds and determined the difference in palatability between freshly dispersed and those buried for six years. The stability of their preferences was tested using a collection of seeds of different species, each of which was offered fresh or after being buried. Carabid beetles readily accepted previously buried seeds as food. In total, Pseudoophonus rufi pes and Amara littorea ate more fresh seeds than previously buried seeds, while the opposite was true for Harpalus affi nis. The seeds of some species were even more attractive to carabids after burial than in the fresh state. For all the species of carabids tested, the diet breadth was similar when the beetles were fed fresh or buried seeds, but the preferences for fresh and buried seed of particular species were correlated only in P. rufi pes and A. littorea. We measured the seed characteristics (mass and viability) likely to be associated with the loss of attractiveness to carabids during burial. The change in carabid consumption was not related to changes in any of these characteristics. This fi nding indicates that factors responsible for variation in seed acceptability are complex. This study provides the fi rst conclusive evidence that invertebrate seed predators will feed on seeds from seed banks, although they prefer fresh seeds.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Convergent photoperiodic plasticity in developmental rate in two species of insects with widely different thermal phenotypes
- Creator:
- Kutcherov, Dmitry, Lopatina, Elena B, and Balashov, Sergei
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- polokřídlí, brouci, mandelinkovití, fotoperiodismus, teplota, Hemiptera, beetles, Chrysomelidae, photoperiodism, temperature, Pyrrhocoridae, Scantius aegyptius, Coleoptera, Timarcha tenebricosa, body size, development, reaction norm, seasonality, 2, and 59
- Language:
- English
- Description:
- Growth and development rates in many insects are affected by photoperiod, which enables insects to synchronize their life histories with seasonal events, but this aspect of insect photoperiodism remains understudied. Here we use several experimental combinations of constant day length and temperature to determine whether there are quantitative developmental responses to photoperiod in the bug Scantius aegyptius and leaf beetle Timarcha tenebricosa. The thermal ecology of these two species is strikingly different: the former is thermophilic and active throughout summer and the latter is spring-active and avoids the hottest time of the year. In accordance with their contrasting natural thermal environments, S. aegyptius survives better and achieves a larger final body mass at the high experimental temperatures, while T. tenebricosa survives better and is heavier at the low experimental temperatures. Despite this polarity, long-day conditions accelerate larval development relative to a short-day photoperiod in both species, and this developmental response is stronger at low temperatures. Our re-visitation of previous literature in light of the new findings indicates that this similarity in photoperiodic response is superficial and that relatively faster development in midsummer is likely to have a different ecological role in summer- and spring-active species. In the former, it may allow completion of an additional generation during the favourable season, whereas in the latter, this acceleration likely ensures that the larval stage, which is vulnerable to heat, is completed before the onset of hot weather., Dmitry Kutcherov, Elena B. Lopatina, Sergei Balashov., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Current and predicted distribution of the rare and threatened beetle Bolbelasmus (Bolbelasmus) unicornis (Coleoptera: Geotrupidae) in Serbia
- Creator:
- Ćurćić, Srećko, Paviević, Dragan , Radović, Dejan, Vesović, Nikola, Bekchiev, Rostislav , Ćurćić, Nina, and Guéorguiev, Borislav
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Geotrupidae, Bolbelasmus unicornis, soil-dwelling beetle, conservation, distribution, Serbia, new findings, GIS, and modelling
- Language:
- English
- Description:
- Bolbelasmus (Bolbelasmus) unicornis (Schrank, 1789) (Coleoptera: Geotrupidae) is a rare and threatened beetle distributed mostly in Central, Eastern and Southeast Europe. As a species of special conservation significance it is included in Annexes II and IV of the Habitat Directive of the European Union. Several new records of this species documented using light traps and soil sampling were recently reported in Serbia (the central part of the Balkan Peninsula). In this paper we present and discuss the current distribution of this species in the region studied based on GIS occurrence data. The distribution is mapped and values of environmental variables within this beetle's range are quantified using GIS technology. In addition, we predict its potential range in Serbia using a model based on the current distribution of this beetle, environmental variables and distribution of its food source.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Dinocampus coccinellae (Hymenoptera: Braconidae) utilizes both Coccinellini and Chilocorini (Coleoptera: Coccinellidae: Coccinellinae) as hosts in Kashmir Himalayas
- Creator:
- Maqbool, Amir, Ahmed, Imtiaz, Kiełtyk, Piotr, and Ceryngier, Piotr
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- blanokřídlí, lumčíkovití, brouci, slunéčkovití, Hymenoptera, Braconidae, beetles, Coccinellidae, Dinocampus coccinellae, Coleoptera, Oenopia conglobata, Priscibrumus uropygialis, parasitoid, host selection, host suitability, 2, and 59
- Language:
- English
- Description:
- Dinocampus coccinellae is a parasitoid wasp usually parasitizing ladybird beetles of the tribe Coccinellini. A field survey conducted between March and November 2016 revealed three hosts of this parasitoid in the Srinagar district of the Indian state of Jammu and Kashmir: two members of the Coccinellini (Oenopia conglobata and Coccinella undecimpunctata) and one of the Chilocorini (Priscibrumus uropygialis). Proportion of the latter (atypical) host that were parasitized was 0.09 and intermediate between that recorded for C. undecimpunctata (0.06) and O. conglobata (0.14). A series of laboratory experiments revealed that while a member of Coccinellini (O. conglobata) was more often attacked by D. coccinellae than a member of Chilocorini (P. uropygialis), the proportions of each species from which parasitoids emerged did not differ significantly. There were no significant differences between D. coccinellae females bred from O. conglobata and P. uropygialis, with respect to selection of the two host species and their suitability for the development of the parasitoid. However, members of the Chilocorini other than P. uropygialis (Chilocorus infernalis and Simmondsius pakistanensis) were rarely attacked by D. coccinellae and parasitoid larvae did not emerge from any of those attacked. The results of our experiments indicate that in Kashmir Himalayas D. coccinellae is adapted to parasitize hosts belonging to both Coccinellini and Chilocorini., Amir Maqbool, Imtiaz Ahmed, Piotr Kiełtyk, Piotr Ceryngier., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Effect of aphid abundance and urbanization on the abundance of Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Honěk, Alois , Martinková, Zdenka , and Štrobach, Jan
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Aphididae, Eucallipterus tiliae, Coleoptera, Coccinellidae, Harmonia axyridis, Tilia, tree, abundance, distribution, population, and urbanization
- Language:
- English
- Description:
- The factors that affect the local distribution of the invasive Harmonia axyridis are not yet completely resolved. Hypotheses predicting positive and independent effects of prey abundance and degree of urbanization on the adult abundance of this species in Central Europe were tested. Populations of H. axyridis were sampled in a period when it was most abundant, by sweeping lime trees (Tilia spp.) at 28 sites along a 20 km transect across urban (western Prague) and surrounding rural areas. The sites differed in aphid abundance (number of Eucallipterus tiliae per 100 sweeps) and degree of urbanization (percentage of the surrounding area within a 500 m radius covered by impervious human constructions). Multiple linear regression analysis of log-transformed data revealed that abundance of H. axyridis (number of adults per 100 sweeps) increased significantly with both aphid abundance (P = 0.015) and urbanization (P = 0.045). The positive relationship between degree of urbanization and abundance of H. axyridis was thus not a side effect of variation in aphid abundance, which was also greater in urban than rural areas. The effect of urbanization might constrict the habitat available to H. axyridis and force this species to aggregate in urban green "refugia". These results point to a plurality of factors that determine coccinellid abundance at natural sites.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
8. Effect of low-temperature storage on the life history parameters and voracity of Hippodamia variegata (Coleoptera: Coccinellidae)
- Creator:
- Sakaki, Samane , Jalali, Mohammad Amin, Kamali, Hashem , and Nedvěd, Oldřich
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Coccinellidae, Hippodamia variegata, cold tolerance, chilling, fertility, ladybird, shelf-life, voracity, and predation capacity
- Language:
- English
- Description:
- For biological control it is necessary to store mass-reared biological control agents when the demand is low. The objective of this study is to increase their shelf life without significantly reducing their fitness. The ladybird Hippodamia variegata is a widespread and voracious aphidophagous predator, with an important role in decreasing the abundance of pest aphids in many parts of the world. We investigated the effect of storage at three temperatures: constant 1°C, constant 6°C, and an alternating thermal regime of 12°C/0°C (the higher temperature for 12 h and the lower one for another 12 h). They were exposed to each of the temperature regimes for either 15, 25, 35, 45 or 60 days. We recorded survival, pre-oviposition period, fecundity and voracity of adult H. variegata following storage. The survival of adult beetles significantly declined with increasing storage duration at all three temperatures. Storage at 6°C up to 35 days and at 12°C/0°C up to 45 days had no significant effects on the fecundity of the ladybirds, but storage for longer significantly decreased fecundity. Beetles stored at 1°C for any of the durations had significantly lower fecundities. Prolonged cold storage caused an increase in the pre-oviposition period at all storage temperatures. Generally, 6°C and 12°C/0°C are the best temperatures for storing the ladybirds as they had the least negative effect on their fitness. The results of this research can help in improving the quality of H. variegata stored for use as biological control agents in the following season.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Effects of 20-hydroxyecdysone on the development and morphology of the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae)
- Creator:
- Tatun, Nujira, Kumdi, Phiraya, Tungjitwitayakul, Jatuporn, and Sakurai, Sho
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- brouci, potemníkovití, beetles, Tenebrionidae, Coleoptera, Tribolium castaneum, 20-hydroxyecdysone, wing growth, α-amylase, prothetelic, 2, and 59
- Language:
- English
- Description:
- The red flour beetle, Tribolium castaneum, is a pest of stored products. It is also regarded as a model species for studying development, genetics, biology, physiology and biochemistry. Recently, it has become a model for use in RNA interference experiments. 20-hydroxyecdysone (20E) is involved in insect metamorphosis and its role in organ development in T. castaneum are based on hormonal treatment in conjunction with RNAi. However, information on the biological, morphological and physiological effects of 20E on T. castaneum is still limited. This study reveals the responses of T. castaneum larvae to injections with various doses of 20E (100, 200, 300, 400 and 500 ng / insect). The results show that larvae injected with 20E reached the prepupal, pupal and adult stages earlier than the control group. Different degrees of morphological change were observed in nine traits, including the appearance of pupal prothetelic organs in the larvae. Moreover, an injection of a high dose of 20E reduced the body weights of the resulting insects at each stage, as well as the length and width of elytra. The enzymatic activity of α-amylase in the resulting adults also decreased significantly. This indicates that injection of 20E caused precocious metamorphosis in T. castaneum by inducing changes in morphology and α-amylase activity, and the optimal concentrations that induce such phenomena were in the range of 100-200 ng / insect. Further investigations are needed to examine the roles of 20E in the regulation of α-amylase in T. castaneum., Nujira Tatun, Phiraya Kumdi, Jatuporn Tungjitwitayakul, Sho Sakurai., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Effects of so-called "environmentally friendly" agrochemicals on the harlequin ladybird Harmonia axyridis (Coleoptera: Coccinelidae)
- Creator:
- Niedobová, Jana , Skalský, Michal , Faltýnke Fric, Zdeněk, Hula, Vladimír , and Brtnický, Martin
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Coccinellidae, Harmonia axyridis, beneficial arthropod, integrated pest management, lethal effect, agrochemicals, Prev B2, and Boundary SW
- Language:
- English
- Description:
- A variety of plant protection products and other agrochemicals are used in agro-ecosystems. Products approved for integrated pest management (IPM) or organic farming should have minimal negative side effects on benefi cial insects. The Asian harlequin ladybird Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) has become a widespread and important generalist predator of certain agricultural pests, mainly aphids, throughout Europe. We studied the effects of two agrochemicals, Boundary SW® (auxiliary plant protection product) and Prev B2® (foliar boron fertilizer), usually regarded as “environmentally friendly” and known to have insecticidal side effects against some fruit and vegetable pests (e.g., aphids, spider mites, weevils), on the last larval instar and adults of Harmonia axyridis. The conventional organophosphate insecticide Reldan 22® was used as a chemical standard for evaluating the lethal effect, because this product is usually effective against a broad spectrum of insects, and indeed was immediately lethal for both the adults and larvae of this species. However, whereas Prev B2® had no effect, adult ladybirds sprayed with Boundary SW® survived only for up to 25 h and also none of the larvae completed their development. Thus, although our experiments were not made under natural conditions, the use of Boundary SW® cannot be recommended for IPM and organic farming in terms of safeguarding insect predators such as Harmonia axyridis until further more detailed testing.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
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