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132. Diapause and post-diapause quiescence demonstrated in overwintering Harmonia axyridis (Coleoptera: Coccinellidae) in northwestern Europe
- Creator:
- Raak-Van Den Berg, C. Lidwien, Peter Willem De Jong, Hemerik, Lia, and Van Lenteren, Joop C.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Coccinellidae, Harmonia axyridis, invasive species, hibernation, diapause, quiescence, pre-oviposition period, semi-field esperiment, 2, and 59
- Language:
- English
- Description:
- The Asian ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is regarded as an invasive species in many parts of the world. In a previous study we hypothesised that H. axyridis enters diapause at the end of October and then shifts to a quiescent state in December in northwestern Europe. In the present study we test this idea of a short, early period of diapause by sampling beetles from their hibernation sites immediately after their migratory flights in October, subsequently keeping them in outdoor cages, and then, after certain time-intervals, measuring the pre-oviposition time under optimal egg-laying laboratory conditions at 25°C. We did this at both short (12L) and long (16L) photoperiods, since a photoperiodic response is an indicator of true diapause, rather than quiescence. A significant, albeit small, difference in pre-oviposition period between the two photoperiods, which disappears in December, corroborates our earlier hypothesis that the ladybirds are in a state of diapause until mid-December. Compared with that of native ladybirds the diapause of H. axyridis generally is relatively short and weak; moreover, it appears to have become shorter over the last decade. This flexibility in diapausing behaviour may be an important factor that contributes to the invasive success of H. axyridis., C. Lidwien Raak-Van Den Berg ... [et al.]., and Obsahuje seynam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
133. Diaspidid (Hemiptera: Coccoidea) size plasticity as an adaptive life history trait
- Creator:
- Hill, M. Garry, Henderson, Rosa C., and Mauchline, Nicola A.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, life history, developmental biology, Diaspididae, fecundity, host plant resistance, polyphagy, plasticity, 2, and 59
- Language:
- English
- Description:
- The size and fecundity of Hemiberlesia lataniae (Signoret) (Hemiptera: Diaspididae) on partially resistant and susceptible kiwifruit (Actinidia spp.) varieties was measured. The size ratio of mature H. lataniae grown on a partially resistant genotype, compared with those on a susceptible genotype, was 0.67-0.51 for 2nd instar exuviae area, 0.32 for adult body area and 0.18 for estimated body volume. The fertility ratio was 0.1, but the pre-oviposition period and the size of the crawlers were the same. Diaspidid scale insects' unusual ability to continue growing after the final moult appears to be a key feature allowing these insects to show extreme size plasticity while retaining the ability to reproduce even when very small. These observations challenge current theories of insect development that postulate the need to achieve a critical weight threshold before the final moult. We suggest that this strategy may have assisted the evolution of polyphagy within the Diaspididae. and M. Garry HILL, Rosa C. HENDERSON, Nicola A. MAUCHLINE.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
134. Differences in the nocturnal flight activity of insect pests and beneficial predatory insects recorded by light traps: possible use of a beneficial-friendly trapping strategy for controlling insect pests
- Creator:
- Ma, Gang and Ma, Chun-Sen
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Lepidoptera, Coccinellidae, Chrysopidae, light trap, phototaxis, 2, and 59
- Language:
- English
- Description:
- The use of light traps for controlling insect pests is restricted since they kill both pests and beneficial insects. It may be a possible to reduce the numbers of beneficial insects trapped by adjusting nightly trapping time based on differences recorded in the timing of the nocturnal flight peaks of target pests and beneficials. To test this, insects were collected hourly over night using black light traps at three locations in China from 2003 to 2005. Groups of lepidopteran and coleopteran pests were selected as the target pests that we would control by trapping and groups of beneficial predatory insects the catches of which needed to be reduced. The highest numbers of Coleoptera were caught between 20:00 and 22:00 h and of most Lepidoptera between 02:00 and 04:00 h. The hourly numbers of predatory insects caught by light traps were evenly distributed throughout the night. A model was developed to describe the relationships between the cumulative proportions of insects caught and time of night. The model accurately describes the flight activity of insects that were mainly caught before midnight, after midnight and evenly throughout a night by using different parameters for the three different insect groups. A beneficial-friendly trapping strategy was developed to reduce the numbers of beneficial insects trapped, which was based on differences in the nocturnal flight activity of pests and beneficial insects and validated by a field study in Shandong province. Results show that this trapping strategy reduced the number of beneficial insects caught by 46% and the electricity consumption by 50% compared to the traditional strategy. Thus this strategy is more beneficial-friendly than the traditional trapping strategy for controlling pests., Gang Ma, Chun-Sen Ma., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
135. Differences in the sugar composition of the honeydew of polyphagous brown soft scale Coccus hesperidum (Hemiptera: Sternorrhyncha: Coccoidea) feeding on various host plants
- Creator:
- Golan, Katarzyna and Najda, Agnieszka
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Coccoidea, Coccus hesperidum, brown scale insects, honeydew, host plants, soft scale, sugar composition, 2, and 59
- Language:
- English
- Description:
- 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.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
136. Differential accumulation of energy by the colour morphs of the pea aphid Acyrthosiphon pisum (Hemiptera: Aphididae) mirrors their ecological adaptations
- Creator:
- Ahsaei, SEyed Mohammad, Tabadkani, Seyed Mohammad, Hosseininaveh, Vahid, Alllahyari, Hossein, and Bigham, Mahdieh
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hemiptera, Aphididae, Acyrthosiphos pisum, adaptation, colour morph, dispersal, available energy, environmental factors, pea aphid, polymorphism, reproduction, specialization, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
137. Discovery of Eutheiini (Coleoptera: Staphylinidae: Scydmaeninae) in Australia, with implications for phylogeny and biogeography of Paraneseuthia
- Creator:
- Jałoszyński, Paweł
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Austrálie, Asie jihovýchodní, Australia, Asia, Southeastern, Coleoptera, Staphylinidae, Scydmaeninae, Eutheiini, Paraneseuthia, taxonomy, phylogeny, biogeography, 2, and 59
- Language:
- English
- Description:
- 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.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
138. Dispersal of Aphytis melinus (Hymenoptera: Aphelinidae) after augmentative releases in citrus orchards
- Creator:
- Zappala, Lucia, Campolo, Orlando, Grande, Saverio Bruno, Saraceno, Francesco, Biondi, Antonio, Siscaro, Gaetano, and Palmeri, Vincenzo
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Aphelinidae, California red scale, biological control, parasitoid, flight range, spatial interpolation, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
139. Divergent patterns in the mitochondrial and nuclear diversity of the specialized butterfly Plebejus argus (Lepidoptera: Lycaenidae)
- Creator:
- Sielezniew, Marcin, Ponikwicka-Tyszko, Donata, Ratkiewicz, Mirosław, Dziekańska, Izabela, Kostro-Ambroziak, Agata, and Rutkowski, Robert
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Lycaenidae, Plebejus argus, mtDNA, EF-1a gene, COI, population structure, phylogeography, sex-biased dispersal, 2, and 59
- Language:
- English
- Description:
- 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.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
140. Diversity of adipokinetic hormones in termites (Isoptera)
- Creator:
- Jedličková, Veronika, Jedlička, Pavel, and Špuláková, Barbora
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, všekazi, Isoptera, termite, adipokinetic hormone, preprohormonal sequence, phylogenetic relationships, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public