Developmental characteristics of the predatory bug Orius similis fed on Tetranychus cinnabarinus were investigated at three constant temperatures (25, 28, and 31°C) under laboratory conditions (75±5% relative humidity and a 14L : 10D photoperiod). The survival of nymphs was highest at 28°C (75.57%) and at this temperature female adults O. similis had the longest oviposition period (21.1 d), the greatest fecundity (40.3 eggs) and the highest potential intrinsic rate of increase (rm: 0.108 d–1). These results suggest that O. similis can maintain greater population densities at 28°C than at the other temperatures tested. In addition, the functional response indicates that the attack rate of O. similis (1.04) and the maximum prey capacity (30.7 spider mites per bug in 24h) are greatest at 28°C. The results of this study provide useful information on the biology and time when to release O. similis in order to reduce the abundance of T. cinnabarinus in cotton fields., Shi-Chang Zhang ... [et al.]., and Obsahuje seznam literatury
Field and laboratory experiments were conducted to assess the time ground beetles (Coleoptera: Carabidae) survive during actual and simulated flood conditions. The effects of three variants of potential flood conditions were tested: (1) beetles trapped on the surface of flood water; (2) beetles trapped in air pockets; (3) submersion of beetles in flood water without access to air. Ground beetles trapped on the surface of water survived more than two weeks (Carabus granulatus – up to 16 days; Oxypselaphus obscurus – up to 22 days). Carabus granulatus in simulated hibernation chambers that had air-pockets also survived for 15 days. The time for which ground beetles submerged without access to air survived differed significantly among species and was affected by season. They survived longest in mid-spring and late-autumn when water temperature is low. In mid-spring, survival times for C. granulatus and Platynus assimilis were 12 days and 9 days, respectively. During late summer and early autumn all species survived for a shorter period of time. In August, at least half of the individuals tested were dead after three days of immersion (water temperature 16–18°C). Removal of both of the elytra of adult of C. granulatus resulted in them surviving immersion for a shorter period, which indicates that air stored in the sub-elytral cavity is used to prolong the period they can survive immersion. The results of these experiments broaden the knowledge of how adult beetles survive seasonal flooding and are able to persist in floodplain habitats., Felix N. Kolesnikov, Arevik N. Karamyan, W. Wyatt Hoback., and Obsahuje seznam literatury
Performance of the invasive horse-chestnut leaf miner, Cameraria ohridella Deschka & Dimic, 1986 (Lepidoptera: Gracillariidae), was studied on two host plants: the white-flowering horse-chestnut Aesculus hippocastanum L. and the Ohio buckeye Aesculus glabra Willd. C. ohridella developed successfully on both host plants; however, mine density and survival were much higher on A. hippocastanum than on A. glabra. The pupal mass and potential fecundity were strongly affected by the host plant on which the larvae fed. On A. hippocastanum pupae were significantly heavier and females more fecund than those on A. glabra. Furthermore, on both host plants there was a significant positive correlation between the number of oocytes in ovaries and pupal body mass, and as a consequence, heavier females produced more eggs. Our study demonstrates that the mine density, survival, pupal mass and potential fecundity were significantly lower on A. glabra than on A. hippocastanum. The observed lower performance of C. ohridella on the exotic host plant was assumed to be due to its poor food quality (nutritional and chemical composition)., Urszula Walczak, Edward Baraniak, Piotr Zduniak., and Obsahuje bibliografii
Tomato spotted wilt virus (TSWV) is one of the most harmful plant viruses and one of its most important vectors is the western flower thrips [Frankliniella occidentalis Pergande (Thysanoptera: Thripidae)]. Recently, we reported the close association of Erwinia sp. gut bacteria with this species of thrips. The first instar larvae acquire these bacteria from their food source. A high proportion of adult western flower thrips transmit TSWV after acquiring the virus during the first larval stage when there are no bacteria in their gut. A considerably lower proportion of adults that acquire the virus early in the second instar transmit virus and none of those exposed to virus late on in the second instar do so. The highest prevalence and total number of symbiotic bacteria are recorded in the guts of second instar thrips. This leads to the hypothesis that the build up of bacteria in the gut reduces the acquisition of TSWV, resulting in a lower capacity to transmit the virus. To test this hypothesis, the transmission of this virus by symbiotic and aposymbiotic adult thrips of the NL3 population was studied. Comparison of virus transmission by adult thrips, the larvae of which either had or lacked gut bacteria and were exposed to virus in either the first or second instar, revealed no difference in the ability of symbiotic and aposymbiotic adults to transmit this virus. We conclude that virus transmission is not affected by the number of the symbiotic bacteria Erwinia sp. present in the gut of thrips larvae., Egbert J De Vries ... [et al.]., and Obsahuje seznam literatury
To explore the debated phylogenetic relationship of two Hesperiidae subfamilies, Pyrginae and Eudaminae, and contribute to the understanding of the evolution of mitogenomic architecture in butterflies, we sequenced the complete mitogenome of Tagiades vajuna. The mitogenome is a typical circular duplex molecule of 15,359 bp. Apart from the standard 22 tRNAs, it has a tandem duplication of trnS(AGN) and trnE, which is unique in lepidopteran insects. Comparison with Ctenoptilum vasava indicates that the trnS1 duplication is not an ancestral state shared with other species of Tagiadini. Independent origin of the trnS1 duplications was further confirmed by the reconstruction of the ancestral character state based on the topology of the phylogram. Furthermore, comparative analysis of mitogenomes with and without tRNA duplications indicates that tRNA duplication does not alter the codon usage pattern. The mitogenome has negative AT- and GC-skews, and it is highly A+T-biased (79.7%). The AT-rich (or control) region (283 bp) contains "ATAGA" and "ATTTA" motifs. Regarding the phylogenetic analysis, we found that removal of the third codon position (3CP) from datasets used for the mitochondrial phylogenomics of Hesperiidae is likely to produce results that are more consistent: Pyrginae were rendered paraphyletic by Eudaminae in both analyses of the dataset from which the 3CP was removed (13 PCGs + all RNAs), but inclusion of the 3CP resulted in a destabilized topology, resulting in both monophyly and polyphyly. We conclude that even shallow-phylogenies of insects should pay close attention to compositional and mutational biases in mitogenomes., Fang-Fang Liu, Yi-Ping Li, Ivan Jakovlić, Xiang-Qun Yuan., and Obsahuje bibliografii
Diaeretiella rapae MacIntosh (Hymenoptera: Aphidiidae) is one of the most common and successful parasitoids of the cabbage aphid. The functional response of D. rapae towards cabbage aphids was examined in laboratory studies at three constant temperatures, 17°C, 25°C and 30°C. D. rapae exhibited a type II functional response at all three temperatures. The search rates were uninfluenced by temperature whereas handling times differed significantly between 17°C and 25°C, and between 17°C and 30°C, but not between 25°C and 30°C. This study is a first-step in the evaluation of the effectiveness of D. rapae as a biocontrol agent of Brevicoryne brassicae at different temperatures., Hamid R.S.Moayeri ... [et al.]., and Obsahuje seznam literarurty
1_Insects feeding on the foliage of oak were studied on a mountain where species of Mediterranean deciduous and evergreen oak coexist. There were 58 insect species (54 Lepidoptera, 1 Coleopteran and 3 Hymenoptera) belonging to twenty families in the assemblage feeding on eight species of Quercus, two of which are introduced from nearby regions. The overlap in occurrence in time and of feeding niches of the insects feeding on the foliage of the different species of oak was determined using the: (a) Poole-Rathcke method, which tests phenological overlap and (b) Petraitis method, which tests niche overlap. This indicated that insect families partition seasonal time in a random and the entire assemblage in a regular way. All groups of insects partitioned season randomly except for the pairs of monophagous-oligophagous and Palearctic-Eurosiberian species, which partition season regularly. Oak folivorous insects correctly perceive the three subgenera of oaks with the exception of the planted Q. robur pedunculiflora. The folivorous insects recorded on the Mediterranean evergreen oaks (subgenus Sclerophyllodrys) differ from those on the other two subgenera (Quercus and Cerris) and co-occurring deciduous trees. The hypothesis of complete general overlap is rejected for groups based on feeding specialization, zoogeographical categories and taxonomic families. The same was the case when the entire insect assemblage was considered. The percentage of specific niche overlap of the folivorous insects is low and greatest among the monophagous species (13.8%) and those with a Mediterranean distribution (15.4%). Voltinism is not very important for this assemblage and only seven species are bivoltine of which four fed on a different species of oak in the second generation., 2_The overall conclusion is that the co-occurrence in space of these species is possible because they occur regularly at different times during the season whereas that of insect groups based on zoogeographical, taxonomic or feeding specialization are randomly dispersed in time., Maria Kalapanida, Panos V. Petrakis., and Obsahuje seznam literatury
Lady beetles (Coleoptera: Coccinellidae) are a classical group for studying the mechanisms that determine local and temporal trends in colour polymorphism. Here we report long term trends in variation in the percentage of different morphs in a population of Hippodamia variegata (Goeze) at Štúrovo, Slovakia (47°48´N, 18°43´E). The morphs differ in the number and location of the spots on their elytra. Beetles were sampled from stands of herbaceous plants using a standard method each year in August over a period of 74 years from 1937 to 2011. Twenty two morphs (out of 74 possible) were recorded in a total sample of 6,984 individuals. Four dominant morphs made up 90% of the total sample and varied in their annual frequency independently of one another. Frequency of "pale" morphs (0–3 spots per elytra), supposedly favoured by a warm climate, increased from 1981 to 2000s’ during a period of climate warming, but only after a decrease that took place between 1937 and 1981, which did not parallel a change in climate. Moreover, the differences in the extent of the melanization of the elytral surface are too small to significantly affect thermoregulation in the different morphs. Therefore, the results presented do not provide unequivocal support for climate change determining the long term trends in the variation in the proportions of the different morphs., Alois Honek ... [et al.]., and Obsahuje seznam literatury
The tendency for self-superparasitism and it's effects on the quality of the parasitoid Ooencyrtus pityocampae (Mercet) (Hymenoptera: Encyrtidae) in parasitizing a new laboratory host, Philosamia ricini (Danovan) (Lepidoptera: Saturniidae), were investigated. In this study, female parasitoids of various ages (1-, 3- and 5-day-old) were tested individually. Parasitoids were provided with 1-day-old P. ricini eggs at ratios of 5, 10, 20, 30 and 40 host eggs per wasp. The tendency to superparasitize was dependent on the female's age and host density. Five-day-old females showed a strong tendency to superparasitize at low host densities. The development time of wasps in superparasitized eggs was longer than that of wasps in singly parasitized eggs. The size and longevity of adult parasitoids decreased significantly with superparasitism. This work contributes to the development of an efficient mass rearing and laboratory rearing of the parasitoid O. pityocampae using a new host., Hilal Tunca, Maurane Buradino, Etty-Ambre Colombel, Elisabeth Tabone., and Obsahuje bibliografii
This paper presents biological notes on two species of Orthoptera: Tettigoniidae that emerged from old spongy-woody galls of Dryocosmus kuriphilus Yasumatsu, 1951 collected in Sicily (Italy) in April 2015: Leptophyes sicula Kleukers, Odé et Fontana, 2010 (Phaneropterinae) and Cyrtaspis scutata (Charpentier, 1825) (Meconematinae). Between the end of April and the first few days of May a total of 30 neanids emerged from the galls, were reared and their life-cycle recorded. While L. sicula laid eggs in groups, C. scutata laid single eggs inside the galls; both species in a few years have adapted to exploiting this new shelter for egg laying. No interaction with the gall inducing insect was noted., Giuliano Cerasa, Bruno Massa., and Obsahuje bibliografii