The ladybird beetle, Cheilomenes sexmaculata (Fabricius), has been extending its distribution in and around urban areas at higher latitudes in Japan over the past 100 years. Between 2003 and 2011, we investigated the seasonal occurrence, aphid prey and population dynamics of this species in an urban park in Osaka City, central Japan. We found that C. sexmaculata completes three generations a year in Osaka. Overwintered adults emerge in March or April and produce two (or rarely one) generations by summer. Second-generation adults aestivate and subsequently produce another generation in autumn. This species feeds on five species of aphids that infest planted shrubs and alien weeds throughout the vegetative season. We analyzed the association between accumulated temperature and when overwintered adults first emerged. In addition, we determined the association between their time of emergence, peak abundance and last occurrence, and meteorological conditions. There was no association between the sum of effective temperatures and termination of adult overwintering. There was, however, an association between first occurrence and peak abundance, and climatic conditions, such as warm temperatures or low humidity. This species maintained a stable population in an urban park by becoming quiescent when climatic conditions were unfavourable or prey was scarce. We discussed these findings in relation to urban environmental factors, such as climate, food conditions and vegetation., Yasuko Kawakami, Kazuo Yamazaki, Kazunori Ohashi., and Obsahuje bibliografii
We conducted a comparative population genetic analysis of levels of genetic variation and its geographical structuring in three closely related species of grasshopper that co-occur in the Mediterranean Basin: Calliptamus italicus, C. barbarus and C. wattenwylianus. In the western part of their distributions 5 populations of C. italicus, 13 of C. barbarus and 10 of C. wattenwylianus were sampled. Bootstrap re-sampling of populations and microsatellite loci within each species indicated a lower level of genetic diversity and higher level of genetic differentiation in C. barbarus, which is less of an outbreak pest species than either of the other Calliptamus species studied. This may be due to lower effective sizes of non-outbreak populations and/or lower gene flow among them., Elodie Blanchet ... [et al.]., and Obsahuje seznam literatury
It is known that chromosomes occupy non-random positions in the cell nucleus. However, it is not clear to what extent their nuclear positions, together with their neighborhood, are conserved in daughter cells. To address specific aspects of this problem, we used the model of the chromosomes carrying ribosomal genes that are organized in clusters termed Nucleolus Organizer Regions (NORs). We compared the association of chosen NOR-bearing chromosomes (NOR-chromosomes) with nucleoli, as well as the numbers of nucleoli, in the pairs of daughter cells, and established how frequently the daughter cells had equal numbers of the homologs of certain NOR-chromosomes associated with individual nucleoli. The daughter cells typically had different numbers of nucleoli. At the same time, using immuno-FISH with probes for chromosomes 14 and 15 in HeLa cells, we found that the cell pairs with identical combinations appeared significantly more frequently than predicted by the random model. Thus, although the total number of chromosomes associated with nucleoli is variable, our data indicate that the position of the NOR-bearing chromosomes in relation to nucleoli is partly conserved through mitosis., M. Kalmárová, E. Smirnov, L. Kováčik, A. Popov, I. Raška., and Obsahuje bibliografii a bibliografické odkazy
Life table data of natural enemies are often used to understand their population dynamics and estimate their potential role in the biological control of pests. Macrosiphum euphorbiae (Thomas) (Hemiptera: Aphididae) is an important pest of several crops and its intrinsic rate of population increase (rm) is 0.282 at 22°C. The life table parameters (immature mortality, developmental time, sex ratio of emerging adults, fecundity and longevity) of Praon volucre (Haliday) (Hymenoptera: Braconidae: Aphidiinae) parasitizing M. euphorbiae were estimated in a climatic chamber at 22 ± 1°C, RH 70 ± 10% and 12 h photophase. Immature mortality was 8.2%, developmental time of males and females was 13.9 and 14.4 days, respectively, and the sex ratio was 0.55 (= fraction of females). Parasitoid fecundity was 504 eggs and longevity 11 days. The net rate of reproduction (R0) was 207.5 females and the intrinsic rate of population increase (rm) 0.281 females/female/day. The time for doubling the population (TD) was 2.45 weeks. P. volucre has a population growth rate similar to that of its host M. euphorbiae and might therefore be a good candidate for the biological control of this aphid. and Juracy Caldeira Lins jr., Vanda Helena Paes Bueno, Diego Bastos Silva, Marcus Vinicius Sampaio, Joop C. van Lenteren.
Although scorpions are an ancient group their method of reproduction is rather complex and poorly studied. This review aims at clarifying some of the aspects of their reproduction that are important for understanding the reproductive ecology of other arthropods, including insects. The following aspects of scorpion reproduction are discussed and reviewed: mating, insemination, fertilization, gestation, parturition and birth. The onset of gestation and its duration are difficult to determine as both depend on the time of fertilization, for which there are no accurate estimates. There are only a few records of the time between birth and emergence of a larva from the maternal envelope in apoikogenic scorpions, which is important for a better understanding of ovoviviparity. All these questions are important as the answers will greatly enhance our understanding of the population ecology of scorpions in terms of the recruitment rates of cohorts and their chances of survival., Michael R. Warburg., and Obsahuje seznam literatury
Macrolophus pygmaeus (Hemiptera: Miridae) is an important predator of pests of horticultural crops and here its ability as a predator of Acyrthosiphon pisum (Hemiptera: Aphididae) is addressed for the first time. The percentage predation of the different aphid instars and the number partially consumed were studied. Our results, obtained using choice and no-choice tests, revealed that M. pygmaeus caught and consumed more young than later instars of A. pisum, which confirms results of previous studies using other species of aphids. We also studied the interactions between predators (male/female) foraging in the same patch. When the prey/predator ratio is kept constant at 10 : 1 the average percentage of aphids completely consumed by individual females or males does not change with increase in the number of foraging predators. However, the number of partially consumed aphids decreased when females shared the same patch. In contrast, there was an increase in the number of aphids partially consumed when two males shared the same patch. The results were discussed in terms of potential predator foraging strategies since intraspecific competition is a key factor modulating the dynamics of prey-predator systems., Juliana Durán Prieto, Vincenzo Trotta, Paolo Fanti, Cristina Castañé, Donatella Battaglia., and Obsahuje bibliografii
n macrophyte-rich lentic ecosystems, higher numbers of damselfly larvae occur in areas where there is structurally complex vegetation than in those where the plant architecture is relatively simple. Biotic interactions rather than morphological constraints are considered to underlie this pattern. We investigated whether the preference of the larvae of the damselfly Enallagma cyathigerum for a particular habitat was retained in absence of prey, predators and/or conspecifics. A series of laboratory choice experiments was conducted in which combinations of sediment and artificial plants differing in structural complexity were offered simultaneously to the larvae. Larvae preferred patches with structurally complex vegetation over patches with simply structured vegetation or lacking vegetation. Patches with simply structured vegetation were preferred over those with bare sediment, but the number of larvae showing a clear choice, which is regarded as an indication of the strength of the preference for a particular habitat, was relatively low compared to the number of individuals responding when complex vegetation was present. Based on the results presented, we conclude that the preference of E. cyathigerum larvae for structurally complex vegetation is independent of the presence of predators, prey or competitors. This suggests that this behaviour of the larvae is either learned or an innate response., Ralf C.M. Verdonschot, Edwin T.H.M. Peeters., and Obsahuje seznam literatury
Intracellular bacteria of the genus Wolbachia (α-Proteobacteria) are the most widespread endosymbionts of insects. Host infection is usually associated with alterations in reproduction, such as cytoplasmic incompatibility, the induction of parthenogenesis and offspring sex ratio bias: all phenomena that may influence host speciation. In the present study, by using well-established molecular tools, we investigated the presence of Wolbachia in leaf beetles of the genus Crioceris and their host plants, which are various species of Asparagus. Multilocus sequence typing of bacterial genes showed that despite their occurrence in the same habitat and feeding on the same plant, two species of Crioceris, C. quinquepunctata and C. quatuordecimpunctata, are infected by two different strains of Wolbachia. C. asparagi, C. paracenthesis and C. duodecimpunctata, which are sympatric with the infected species, do not harbour the bacterium. Interestingly, DNA of Wolbachia was detected in host plant tissues that are exploited by the beetles, providing evidence for the horizontal transmission of the bacterium between beetles and their host plants. Moreover, Wolbachia was detected in species of Crioceris that are not closely related., Michał Kolasa, Matteo Montagna, Valeria Mereghetti, Daniel Kubisz, Miłosz A. Mazur, Łukasz Kajtoch., and Obsahuje bibliografii
Babesia caballi (Nuttal, 1910) is one of the causative agents of equine piroplasmosis which causes economic losses to horse industry in China. There is an urgent need for rapid detection method for B. caballi infection in Xinjiang Province, China. To prepare monoclonal antibodies (mAbs) against Bc48 gene of B. caballi (Xinjiang local strains) and establish colloidal gold-immunochromatographic (ICT) assay for diagnosis of the disease, recombinant Bc48 was expressed and purified from Escherichia coli. With purified Bc48 as immunogen in mice, three hybridoma cells named 11F4, 1H2 and 7F4 secreting mAbs against Bc48 of B. caballi were obtained, which showed strong reaction with recombinant Bc48 and Bc48 gene transfected cells. Furthermore, colloidal gold labelled ICT assay based on purified Bc48 recombinant antigen and its mAb was developed. The ICT assay showed high sensitivity and specificity and no cross-reaction with Theileria equi (Laveran, 1901). Total of 56 horse serum samples collected from Xinjiang were tested by ICT and compared with the detection by commercial ELISA kit. The results showed that 32 out of 56 serum samples were positive by ICT and 33 were positive by ELISA. ICT assay had high coincidence (98%) to the reference ELISA kit. mAbs and ICT developed in this study could be provided as an efficient diagnosis tool for infection with B. caballi in horse in Xinjiang area., Panju Wang, Jingjing Song, Ruiqi Song, Mengyuan Zhang, Lijiang Wu, Fangxin Li, Yan Yan, Jiyong Zhou, Bayin Chahan, Min Liao., and Obsahuje bibliografii
Some free-living amoebae are a potential threat to human health. The best known species are those of the genus Acanthamoeba Volkonsky, 1931, which cause Acanthamoeba keratitis, granulomatous amoebic encephalitis and other forms of tissue inflammation. The aim of the present study was to search for potential pathogenic genotypes of free-living amoeba in the sand in children's playgrounds. Our results confirmed that free-living amoebae were present in all examined playgrounds. Sequences of the 18S rDNA have shown that all isolated potentially pathogenic strains of amoebae belong to genotype T4 of Acanthamoeba. The potential pathogenicity of isolates was confirmed on mice. The presence of pathogenic amoebae in the examined sand may be a potential source of human infection., Marcin Cholewiński, Piotr Solarczyk, Monika Derda, Agnieszka Wojtkowiak-Giera, Edward Hadaś., and Obsahuje bibliografii