German cockroaches spend most of the day in aggregations within shelters, which they leave in nocturnal foraging trips; cockroaches are rarely seen outside shelters during daylight hours. However, when population density exceeds shelter availability, diurnal aggregations form in exposed, unsheltered locations. To determine if shelter availability affects fitness of B. germanica, we reared cohorts of nymphs in laboratory arenas with or without shelters, and measured reproduction and longevity of tagged adults. When shelters were available in arenas, nymphs developed faster, adults gained more body mass, and females produced more fertile oothecae than when arenas lacked shelters. Therefore, shelter alone has a significant positive effect on growth and reproduction of B. germanica, and reducing or eliminating shelters should affect population growth of B. germanica in residential and industrial settings. and César Gemeno, Gregory M. Williams, Coby Schal.
In the Mediterranean area the orthopterans Calliptamus barbarus barbarus, Dociostaurus maroccanus and Tettigonia viridissima are considered to be pests of major economic importance crop plants. The aim of the present study was to evaluate the area of leaf of vine, cotton and potato plants consumed by these Orthoptera at two temperatures. Leaf area was determined for each plant species before the leaves were provided to the insects. Virgin male and female adults were allowed to feed on a leaf of each plant species and the area of leaf consumed was determined after 24h at 25 and 30°C. Results showed that temperature had a significant affect on consumption by both males and females of all the species examined, and it was higher at 30°C. The influence of plant species was not significant for C. barbarus barbarus. D. maroccanus and T. viridissima, however, consumed a greater area of potato leaves than of the other species of plants. Females consumed more food than males in all the species tested. The results of the present study provide a first approximation of the area of leaf consumed and the potential loss of foliage these plants might suffer if attacked by the three species of Orthoptera tested., Spyridon A. Antonatos, Nikolaos G. Emmanuel, Argyro A. Fantinou., and Obsahuje seznam literatury
In order to enhance the mass production of the house fly, Musca domestica, five aspects of its oviposition biology were analyzed. Oviposition substrate and the manner of its presentation, the composition of the diet of the adults, size of the pupae and numbers of flies in a cage were identified as critical. Females preferred to lay eggs on a substrate which was presented within a shelter and with increased linear edges against which the flies could oviposit. Different types of oviposition substrate resulted in comparable yields of eggs. The presence of an oviposition attractant (ammonia) in the manure was found to have a potentially positive effect on female fecundity. Egg yield increased when two protein sources (yeast and milk) were included in the adult diet. However, flies fed a mixture of sugar and yeast laid over 50% fewer eggs than those fed the same proportion of sugar and milk. The fecundity of flies decreased with increase in the number of flies per cage, but the highest total number of eggs per cage was obtained when the flies were most crowded (14.2 cm3 per fly). The size of the pupae did not significantly affect egg production. and Berta Pastor, Helena Čičková, Milan Kozánek, Anabel Martínez-Sánchez, Peter Takáč, Santos Rojo.
Transgenic lines of silver birch (Betula pendula) carrying the sugar beet chitinase IV gene were used to study the effects of the heterologous expression of a transgenic chitinase on the performance of lepidopteran herbivores. The effect of wounding the leaves of birch on the performance of lepidopteran larvae and the growth of trees was also studied. Larvae of Orgyia antiqua L., Lymantriidae, and Phalera bucephala L., Notodontidae, were separately fed on the leaves of transgenic and wild-type birch, and their performance measured using nutritional indices. The relative growth rate (RGR) of O. antiqua larvae fed transgenic leaves was significantly lower than that of larvae fed wild-type leaves. Furthermore, there is little evidence that transgenic chitinase affects survival but it was lowest for the group of larvae fed leaves with the highest expression of chitinase IV. Wounding did not have a significant effect on the performance of the larvae or on the growth of the branches of the trees. The growth of branches of particular transgenic lines, however, was significantly associated with tree line. The performance of P. bucephala larvae fed leaves of transgenic and wild-type birches did not differ. The leaves used in both experiments from transgenic trees were shorter than those from wild-type trees. Using transgenic birch expressing sugar beet chitinase IV to improve the resistance of birch to fungal diseases can have negative effects on O. antiqua larvae feeding on the leaves of these birches. P. bucephala, however, was not similarly affected, which indicates that these two ecologically similar lepidopteran species may differ in their response to transgenic chitinase., Liisa Vihervuori ... [et al.]., and Obsahuje seznam literatury
Female hybrids of the cross Chironomus t. thummi female × Ch. t. piger male which are largely affected by the sterility inducing Rud syndrome were backcrossed with males of both parental strains. The aim of the study was to provide information about those egg volumes that are insufficient for a normal embryogenesis and to ascertain whether in the hybrids the lethally small egg size represents a new abnormal trait of the Rud syndrome. The egg masses obtained contain eggs of very different sizes with volumes ranging from 0.5 nl to 3.49 nl. Embryo mortality is unusually frequent in those eggs of the backcrosses and of the parental strains that have volumes smaller than 1.5 nl. An egg volume of 1.5 nl represents in Ch. thummi the lower limit for those volumes that are sufficient for a normal embryogenesis. Mortality increases with decreasing egg size, reaching 100% in backcross eggs with volumes of 0.99 nl and smaller. Small egg size is a new trait of the Rud syndrome affected thummi female × piger male hybrids. This trait is part of a postzygotic reproductive isolation barrier between thummi and piger and manifests first in the backcrosses. Most backcross eggs show volumes between 1.5 nl and 2.99 nl. Within this volume range the amount of mortality does not depend upon egg volume. Here, embryo death is great in the backcrosses but normal in the parental strains. The high frequency of embryo death in the backcrosses must be predominantly due to the action of the Rud syndrome and a second hybrid syndrome, called HLE syndrome. Since further characteristic traits of these syndromes could be detected in surviving backcross individuals, the study demonstrates the occurrence of the syndromes in this generation also. Therefore, the postzygotic reproductive isolation mechanism of both hybrid syndromes is effective in the hybrids and in their progeny as well., Klaus Hägele, Monika Kasper-Sonnenberg, 4 obrázky, 2 tab., and Lit.
Thelytokous parthenogenesis is a type of sex determination in which females are produced from unfertilized eggs. Genetic and endosymbiont-induced forms of thelytoky have been described in the Hymenoptera. Our study has revealed that Wolbachia, Cardinium, Spiroplasma and other endosymbionts are probably absent in Iberian populations of harvester ants, Messor barbarus and Messor capitatus (Hymenoptera: Formicidae: Myrmicinae) and are thus not involved as factors in the sex determination of these two species. Our results lend weight to previous suggestions that bacterial parthenogenesis induction in Hymenoptera is probably limited to the reproductive systems of chalcidoid and cynipoid parasitoid wasps (Hymenoptera: Apocrita: Chalcidoidea and Cynipoidea, respectively)., Paloma Martínez-Rodríguez ... [et al.]., and Obsahuje seznam literatury
The pistachio psylla, Agonoscena pistaciae Burckhardt & Lauterer (Hemiptera: Psyllidae), is a major pest of pistachio trees throughout the pistachio producing regions in Iran. The effect of temperature on the developmental rates of eggs and nymphs of A. pistaciae was determined at different constant temperatures, i.e. 15, 20, 25, 30, 32.5 and 35 ± 0.5°C. The relationships between temperature and developmental rates were described by linear and the non-linear Lactin models. These models were evaluated based on R2, RSS, AIC and R2adj. The estimated value of the lower temperature threshold for egg, nymph and egg to adult development based on the linear model was 8.06, 10.38 and 9.97°C, respectively, and based on the Lactin model was 8, 11.55 and 11.2°C, respectively. Thermal constants estimated using the linear model, were 88.5, 243.90 and 333.33 DD, respectively, for egg, nymph and egg to adult development. These results indicate that the linear model gives a better description of the relationship between developmental rate and temperature for A. pistaciae than the non-linear model. These results could be incorporated into forecasting models used in the integrated pest management of this pest. and Mohammad Reza Hassani, Abbas Arbab, Hamzeh Izadi, Gadir Nouri-Ganbalani.
Periodikum vzniklo v roce 1904 pod názvem Časopis České Společnosti Entomologické (Acta Societatis Entomologicae Bohemiae) současně s Českou společností entomologickou (ČSE) jako její fórum. O jeho vznik, počáteční kvalitu a široký záběr se významně zasloužil první předseda ČSE František Klapálek. Od té doby tento titul existuje bez přerušení v různých podobách, kvalitě a pod různými názvy dodnes. V roce 2014 vychází jeho 111. ročník. and Petr Švácha.
In order to determine when during the development of H. armigera CYP6B6 is expressed, we measured the width of the head capsule, the length of the body and weight of the different life stages of the cotton bollworm reared under laboratory condition. The larvae took about 20 d to complete their development under these conditions, the pre-pupae about 4 d, pupae about 9 d, and the adults lived for about 9 d and the eggs took about 4 d to hatch. Knowing this it was possible to determine the pattern of cytochrome P450 CYP6B6 expression at different stages in the life cycle of H. armigera using real-time quantitative polymerase chain reaction (RT-qPCR). The CYP6B6 gene was expressed in all the developmental stages of the cotton bollworm. The results indicate that the level of expression was lower in the egg, pre-pupal, pupal and adult stages than in larvae. The level of expression of CYP6B6 decreased from the 1st to the 3rd instar larva, with the lowest level recorded in the 3rd instar larvae and then increased reaching its highest value in 6th instar larvae. A similar trend in the expression of CYP6B6 was detected using immunohistochemistry. As the results show, more efficient control of the cotton bollworm can be achieved if insecticides are applied when the larvae of H. armiger are in the 3rd instar, because at that stage the eat little food and there is a low level of detoxifying enzymes in the larvae., Xuetao Zhang ... [et al.]., and Obsahuje seznam literatury
The cixiid planthopper Hyalesthes obsoletus Signoret is an efficient vector of the stolbur phytoplasma, the cause of various crop diseases. In the field, this monovoltine species feeds on a wide variety of woody and herbaceous plants. It overwinters as larvae on the roots of its host plants. During this study, we collected adults mainly from lavender (Lavendula angustifolia Miller), bindweed (Convolvulus arvensis L. and C. sepium L.), hoary cress (Cardaria draba L.), and occasionally from plantain (Plantago cynops L.), toadflax (Linaria striata L.), bedstraw (Galium verum L.), and mountain savory (Satureia montana L.). Fertility of field collected females from sites at two different elevations differed significantly. Fertility at 300 m (50.6 eggs per female; N = 28) was more than twice that at 900 m (22.8 eggs per female; N = 19). Only one specimen of the species was found to be parasitized by an undetermined species of Dryinidae (Hymenoptera). H. obsoletus was reared in controlled conditions on lavender. Unlike in the field, larvae developed in the laboratory at the base of the host plant and on basal shoots. Egg incubation averaged 7 ± 1.2 weeks (N = 10). Total development time from egg to adult averaged 27 ± 4 weeks (N = 5) on lavender. A morphological description of the five instars is provided. The study was supplemented by scanning electron microscopy. Particular attention was paid to the structure of the wax-plates and the absence of compound eyes in the early larval stages., René Sforza, Thierry Bourgoin, Stephen W. Wilson, Elisabeth Boudon-Padieu, and Lit