Plant chemical composition is an important determinant of host plant-insect interactions. For many insects sugars are the main factors determining the acceptability of a plant. This study investigated changes in plant chemical composition and differences in sugar composition of different host plants induced by the feeding of Coccus hesperidum L. (Hemiptera: Sternorrhyncha: Coccoidea). Present in plant extracts and honeydew there were three monosaccharide sugars: glucose, fructose and arabinose, and one disaccharide - sucrose. Arabinose was only found in extracts of Ficus benjamina plants. The sugar content of the honeydew was greater than in the extracts of control plants and lower than that in the extracts of infested plants. The honeydew collected from C. hesperidum feeding on the three plant species differed significantly in sugar content. Extracts of coccid infested plants of the three species used in this study contained more sugar than the un-infested control plants. The results show that honeydew composition of scale insects differ and the differences reflect the chemical composition of the host plants. and Katarzyna Golan, Agnieszka Najda.
The pea aphid, Acyrthosiphon pisum (Hemiptera: Aphididae), is a well-studied species in terms of its colour polymorphism, where it occurs as two distinct colour morphs, red and green. It is proposed that the occurrence and maintenance of this polymorphism is an adaptive response to environmental factors, in particular natural enemies and host plant quality. We hypothesized that these adaptations are directly mirrored in the energy reserves accumulated by the different colour morphs during their pre-adult stages and reflect their specialization for particular ecological roles. We quantitatively measured the different energy reserves of red and green pea aphids and found that the total energy reserves of these morphs did not differ. Interestingly, these reserves were made up of different components in the red and green colour morphs. There was a higher percentage content of water-soluble carbohydrates and lipids in the red clones and higher percentage content of protein in green clones. These finding are in accordance with green clones being more fecund than red ones and needing more protein for reproduction than red clones, which produce more winged offspring when crowded or in response to the presence of natural enemies and so, need more lipids and carbohydrates to fuel their walking and flight. Apparently, different colour morphs are physiologically specialized to adjust their energy reserves in relation to their specific ecological adaptations and maximize their fitness in terms of dispersal, reproduction, defense and survival., Seyed Mohammad Ahsaei ... []., and Obsahuje seznam literatury
The scydmaenine tribe Eutheiini is recorded from Australia for the first time. Paraneseuthia carltoni sp. n. and P. booloumba sp. n. are described and illustrated, both from Queensland. In a parsimony-based phylogenetic analysis using adult morphological characters including genital features, the Australian species together with the Melanesian type species of Paraneseuthia Franz, P. peckorum Franz, were found to be more closely related to East Palearctic congeners than to most of the Paraneseuthia in the Sunda-Papuan area. The topology of the tree and biogeographic data suggest a Sundaland origin of this genus, with three major dispersal routes from a center located in present-day Sumatra: (i) north-eastern colonization of the Palearctic Far East, via a continental or island-arc route; (ii) south-eastern dispersal to East Australia; and (iii) eastern dispersal to Melanesia, possibly via the Quaternary Outer-Melanesian Arc. The important role of dispersal in the evolution of Paraneseuthia is supported by the presence of this genus on isolated volcanic islands, such as the southern Moluccas and Fiji, which were never connected to larger land masses. and Paweł Jałoszyński.
he efficacy of natural enemies in controlling pests under field conditions is largely correlated with their capacity to spread within infested crops. In this study the spatial dispersal of the California red scale parasitoid Aphytis melinus DeBach (Hymenoptera: Aphelinidae) was evaluated in the field after augmentative releases. The experiment was conducted in 2007 in six 1-ha plots in a Sicilian citrus orchard under integrated pest management. A total of 180,000 A. melinus adults was released in each of three plots and the other plots were left as untreated control. The flight range of the parasitoid was evaluated, for 35 days after the release, on 16 trees per each plot, located at 20 and 40 m from the central release point using yellow sticky traps activated with Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) sexual pheromone and by monitoring the percentage parasitism of the scale on fruits and twigs. The effects of the distance from the release point and density of susceptible stages of host on parasitoid dispersal were evaluated. The number of wasps captured during the whole trial was greater in the traps located 20 m from the release point than in those at 40 m and in the control plots. Aphytis melinus dispersed over distances less than 40 m based on both the lower percentage parasitism and numbers captured recorded at distances of 40 m. The results are discussed in the context of the biological control of California red scale in citrus orchards by means of wasp releases. In particular, the release points should be no more than 40 m apart for a quick and homogeneous colonization of the area treated., Lucia Zappala ... [et al.]., and Obsahuje seznam literatury
Plebejus argus is a model species for studying the biology, population ecology and genetics of butterflies. It is patchily distributed throughout most of its European range and considered to be sedentary. Habitats of the butterfly have to encompass two vital larval-resources, i.e. specific food plants and ants, since caterpillars are obligatorily myrmecophilous. The genetic structure of nine P. argus populations (85 individuals) was studied at an intermediate geographical scale (Eastern Poland, diameter of about 400 km) using two kinds of molecular markers i.e. COI (mtDNA) and EF-1α (nuclear gene). Both markers were highly variable with as many as 16 haplotypes and 39 alleles, respectively. Great genetic differentiation in the COI gene was detected (overall FST = 0.411, P < 0.001) but little genetic differentiation in the EF-1α gene (FST = 0.021, P < 0.001). The number of COI haplotypes (ranging from one to seven) and their distribution varied considerably among P. argus populations. The possibility that this heterogeneity was related to Wolbachia was excluded as this endoparasitic bacterium was not detected in samples from any of the populations studied. PCA and SAMOVA analyses divided the sampled populations into two or three groups, which could indicate different colonization routes. Moreover, the differences in genetic differentiation with respect to mtDNA and nuclear markers may suggest male-biased dispersal of P. argus at a larger scale. The hypothesis that females are philopatric is consistent with direct observations of the restricted colonization abilities of the butterfly, while the relatively homogeneous genetic structure revealed by previous allozyme studies in some areas might be explained by the possible higher mobility of males. and Marcin Sielezniew, Donata Ponikwicka-Tyszko, Miroslaw Ratkiewicz, Izabela Dziekanska, Agata Kostro-Ambroziak, Robert Rutkowski.
In this study we report on the structural diversity of adipokinetic hormones (AKHs) in the evolutionarily oldest group of social insects, the termites (Isoptera). Using molecular methods combined with in silico bioinformatic analysis, we studied and compared the sequences coding for these neuropeptides in thirteen species of five families of Isoptera. There are three types of AKH octapeptides in termites: Empusa pennata adipokinetic hormone (Emppe-AKH; pQVNFTPNWamide), Microhodotermes viator corpus cardiacum peptide (Micvi-CC; pQINFTPNWamide) and Periplaneta americana cardioaccelerating hormone (Peram-CAH-I; pQVNFSPNWamide). Of these the Peram-CAH-I was the most frequently bioactive form detected in representatives of four out of the six families studied. The complete AKH preprohormones in the termites studied shared at least an 84% amino acid similarity. In agreement with current phylogenetic scenarios of termites as an internal monophyletic clade nested within cockroaches (Blattaria) in the proximity of the family Blattidae, our phylogenetic analysis of the AKH precursor sequences (in the absence of data for the Cryptocercidae) placed the Blattidae (Periplaneta americana) as a sister group of termites and the AKHs of other cockroach families (Blattellidae and Blaberidae) were more divergent from those of termites. Representatives of the basal termite families Mastotermitidae and Archotermopsidae (but also one rhinotermitid genus Prorhinotermes) occurred separately from the phylogenetically advanced lineage (Rhinotermitidae and Termitidae), and Neotermes (Kalotermitidae) was sister to all other termites included., Veronika Jedličková, Pavel Jedlička, Barbora Špuláková., and Obsahuje bibliografii
The chotts in Algeria are temporary salt lakes recognized as important wintering sites of water birds but neglected in terms of the diversity of the insects living on their banks. Around a chott in the wetland complex in the high plains near Constantine (eastern Algeria), more than half of the species of plants are annuals that dry out in summer, a situation that prompted us to sample the vegetation in spring over a period of two years. Three zones were identified based on an analysis of the vegetation and measurements of the salt content of the soils. Surveys carried out at monthly intervals over the course of a year revealed temporal and spatial variations in biodiversity and abundance of grasshoppers. The inner zone is colonized by halophilic plants and only one grasshopper species (Dericorys millierei) occurs there throughout the year. Two polyphagous species of Calliptamus, which can feed on halophilic plants migrate from adjacent areas into the inner zone in August to feed on the plants growing there. The other species of grasshoppers remain in outer zones as they are unable to feed on halophilic plants. The greatest abundance of grasshoppers from August to winter was recorded in the inner zone and in spring and early summer in the outer zones. The dependence of D. millierei on bushes of Amaranthaceae and its moderate flight ability, features of the family Dericorytidae, limit this species ability to colonize neighbouring chotts., Sarah Mahloul, Abboud Harrat, Daniel Petit., and Obsahuje bibliografii
Kniha M. Kottelata a J. Freyhofa Handbook of European Freshwater Fishes (Cornol a Berlin 2007) je recenzována s rozsáhlým komentářem a je poukázano na její vpravdě „revoluční“ pojetí. Kniha jasně ukazuje na předtím netušenou velkou diverzitu evropských sladkovodních ryb a dokumentuje existenci téměř 550 původních a 33 nepůvodních druhů ryb, kde každý druh v knize doprovází popis, diagnostické znaky a většinou dokonalé fotografie. Význačným poselstvím knihy je také upozornění na různý stupeň ohrožení u téměř 40 % existujících druhů., The Handbook of European Freshwater Fishes by M. Kottelat and J. Freyhof (Cornol and Berlin 2007) is reviewed with extensive comments showing its indeed “revolutionary” concept. The book clearly demonstrates the previously unexpected great diversity of European freshwater fishes and documents the occurrence of nearly 550 autochthonous and 33 alien species (each species is described, diagnosed, in most cases accompanied by excellent photos). The significant message of the book is also the fact that almost 40 % of recorded species are under various degrees of threat., Petr Ráb., and Obsahuje seznam literatury
Článek představuje dlouhodobý výzkum vodního hmyzu, především jepic (Ephemeroptera), pošvatek (Plecoptera) a chrostíků (Trichoptera), v České republice. V jeho více než stoleté historii jsou určitými milníky období přelomu 19. a 20. stol. a práce F. Klapálka a druhá polovina minulého století, kdy probíhal organizovaný faunistický výzkum vedený V. Landou a M. Zelinkou. Data a materiál nashromážděné během celého tohoto období nyní umožňují provést unikátní porovnání výskytu druhů v současnosti a minulosti na stovkách lokalit po celé České republice. Jeho výsledky přinášejí cenné informace o vývoji společenstev vodního hmyzu., This article presents long-term investigation into aquatic insects, particularly mayflies (Ephemeroptera), stoneflies (Ephemeroptera) and caddisflies (Trichoptera), in the Czech Republic. Within its more than hundred-year history, two milestones can be recognised: the turn of the 20th century with the famous work of F. Klapálek, and the second half of the last century with extended faunistic research conducted by V. Landa and M. Zelinka. The data and material gathered during the entire period enable us to compare species distribution at hundreds of localities covering the whole Czech Republic over the hundred years. The results show valuable information on the development of communities of aquatic insects., and Tomáš Soldán ... [et al.].
Among the semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields are potential habitats for the natural enemies of insect pests. As insects are sensitive to a variety of flower traits, we hypothesized that mixtures with high functional diversity attract and support a higher abundance and species richness of aphid flower visiting predators than mixtures with low functional diversity. During a field experiment, repeated over two years (2014 and 2015) in Gembloux (Belgium), aphid predators (i.e., lacewings, ladybeetles and hoverflies) were pan-trapped in five sown flower mixtures (including a control mixture, with three replicates of each mixture) of low to high functional diversity based on seven traits (i.e., flower colour, ultra-violet reflectance and pattern, start and duration of flowering, height and flower class, primarily based on corolla morphology). In both years, the species of flowering plants in the sown mixtures (i.e., sown and spontaneous flowers) were listed, and the realized functional diversity in each plot calculated. Over the two years, a high functional diversity was not associated with high abundance and richness of aphid predators. Moreover, ladybeetles, which made up the majority of the predators trapped, were more abundant in mixtures with very low or intermediate functional diversity at sowing, especially in 2014. We hypothesize that certain flowers, which were abundant in certain mixtures (and not in those exhibiting the highest functional diversity), attracted predators and were sufficiently abundant to support them. Our results present novel information that could be used for developing flower mixtures that provide effective ecosystem services, such as pest control., Séverin Hatt, Roel Uyttenbroeck, Thomas Lopes, Pierre Mouchon, Julian Chen, Julien Piqueray, Arnaud Monty, Frédéric Francis., and Obsahuje bibliografii