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42. Ovaries of Puto superbus and Ceroputo pilosellae (Hemiptera: Coccoidea): morphology, ultrastructure, phylogenetic and taxonomic implications
- Creator:
- Michalik, Anna, Kalandyk-Kolodziejczyk, Malgorzata, Simon, Ewa, Kobialka, Michal, and Szklarzewicz, Teresa
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hemiptera, Coccoidea, Puto superbus, Ceroputo pilosellae, ovariole, germ cells, trophocyte, oocyte, scale insects, 2, and 59
- Language:
- English
- Description:
- Ovaries of Puto superbus and Ceroputo pilosellae are composed of numerous short telotrophic ovarioles that are arranged around the distal part of the lateral oviduct. An individual ovariole consists of a distal trophic chamber (= tropharium) and proximal vitellarium. The tropharia enclose individual trophocytes (= nurse cells) and early previtellogenic oocytes termed arrested oocytes. A single oocyte develops in each vitellarium. Analysis of serial sections has shown that ovarioles of P. superbus contain from 16 to 51 germ cells (13–43 trophocytes, 2–7 arrested oocytes, 1 developing oocyte) while those of C. pilosellae from only 8 to 10 germ cells (5–7 trophocytes, 0–2 arrested oocytes, 1 developing oocyte). The classification and phylogeny of scale insects are discussed taking into consideration the results of this study., Anna Michalik ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
43. Patterns of morphometric variation among species of the genus Cicada (Hemiptera: Cicadidae) in the Mediterranean area
- Creator:
- Simoes, Paula Cristina and Quartau, Alberto
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Cicada, morphology, morphometry, Portugal, Greece, and Turkey
- Language:
- English
- Description:
- Selected populations of five closely related species of the genus Cicada L. were collected mainly on the Portuguese, Greek and Turkish mainland, as well as on several Aegean islands. Ten morphometric traits of external structures and seven of male genitalia were analysed and the results revealed patterns in morphometric variation for each species. Only C. lodosi was always completely discriminated by both character sets and C. barbara by the male genitalia analysis. For the remaining species there was great overlap between the clusters. Body length, of the external morphological structures, and measurements of the pygophore, of the male genitalia, were the best variables for identifying C. lodosi and C. barbara. The present morphometric analyses revealed that divergence in morphology is much less pronounced than the divergence in acoustic signals and DNA. Thus, the congruence between morphological divergence, namely at the level of the external structures, and both behavioural (acoustic) and genetic divergence is quite low.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
44. Polygalacturonase gene expression and enzymatic activity in salivary glands of laboratory reared and wild populations of Lygus lineolaris (Hemiptera: Miridae)
- Creator:
- Fleming, Daniel, Krishnan, Natraj, and Musser, Fred
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, polokřídlí, klopuškovití, bavlna, genová exprese, slinné žlázy, Hemiptera, Miridae, cotton, gene expression, salivary glands, Lygus lineolaris, polygalacturonase, enzyme activity, 2, and 59
- Language:
- English
- Description:
- Lygus lineolaris (Palisot de Beauvois, 1818) (tarnished plant bug) is a serious pest of cotton (Gossypium hirsutum L.) in the Delta region as compared to cotton in the Hills region of the state of Mississippi in USA. The reason for this is unclear but it was hypothesized that the plant cell wall degrading polygalacturonase enzyme system in the salivary glands of L. lineolaris from the Delta could be better adapted for cotton, which is grown more predominantly in the Delta region than in the Hills region. Expression analysis of three primary polygalacturonase genes (LlPG1, LlPG2 and LlPG3) was conducted in laboratory reared and field collected populations of L. lineolaris. Assay of polygalacturonase enzyme activity was also conducted to compare wild collected populations. Initial laboratory and field data revealed gene expression differences in sex, age, region, and host plant which guided the direction of our subsequent study during 2013 and 2014. Based on the results of this study, we propose that the three genes studied may not be reflective of the entire polygalacturonase enzyme system and may not be solely responsible for the observed adaptation of L. lineolaris to cotton in the Delta region than in the Hills region. Analyses also revealed that the expression of the three targeted polygalacturonase genes was affected by the host plant from which the insects were collected and that adults had higher polygalacturonase expression than nymphs. Taken together, our results provide strong evidence for developmental stage specific and host plant based change in expression of PG genes in the salivary glands of L. lineolaris. This, however, was not reflected in total polygalacturonase enzyme activity which was not significantly different between regions, hosts, sex, or developmental stage., Daniel Fleming, Natraj Krishnan, Fred Musser., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
45. Predation by Macrolophus pygmaeus (Hemiptera: Miridae) on Acyrthosiphon pisum (Hemiptera: Aphididae): Influence of prey age/size and predator's intraspecific interactions
- Creator:
- Durán Prieto, Juliana, Trotta, Vincenzo, Fanti, Paolo, Castañé, Cristina, and Battaglia, Donatella
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, polokřídlí, klopuškovití, mšicovití, Hemiptera, Miridae, Aphididae, Macrolophus pygmaeus, Acyrthosiphon pisum, pea aphid, polyphagous predator, prey selection, partial prey consumption, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
46. Predation of Bradysia sp. (Diptera: Sciaridae), Liriomyza trifolii (Diptera: Agromyzidae) and Bemisia tabaci (Hemiptera: Aleyrodidae) by Coenosia attenuata (Diptera: Muscidae) in greenhouse crops
- Creator:
- Tellez, Maria del Mar, Tapia, Gervasio, Gamez, Manuel , Cabello, Tomas, and Emden, Helmut F. van
- Type:
- article, model:article, and TEXT
- Subject:
- Greenhouse crops, functional response, predator-prey population dynamics, Diptera, Sciaridae, Bradysia sp., Agromyzidae, Liriomyza trifolii, Muscidae, Coenosia attenuata, Hemiptera, Aleyrodidae, and Bemisia tabaci
- Language:
- English
- Description:
- We studied the predation behaviour of the "hunter fly" (Coenosia attenuata Stein) in the laboratory and greenhouse. In the laboratory, which was conducted at 25°C at 60-80% RH, with a 16L : 8D photoperiod, we examined the functional response of this species to three different pests, namely the sciarid fly (Bradysia sp.), the tobacco whitefly (Bemisia tabaci) and the leaf miner Liriomyza trifolii. In the greenhouse, we studied the population dynamics of the predator and its prey on pepper and water melon crops grown in southern Spain. Adult hunter flies were found to exhibit a type I functional response to adult sciarid flies and whiteflies, but a type II response to adult leaf miners. The type II response was a result of the greater difficulty in capturing and handling leaf miners compared to the other two species. The dynamics of the predator-prey interaction in the greenhouse revealed that the predator specializes mainly on adult sciarids and that the presence of the other prey can be supplemental, but is never essential for survival of the predator; this, however, is crop-dependent. The results on the dynamics of the predator-prey systems were obtained through a known population dynamics model with modifications.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
47. Relation between plant water status and Macrosiphum euphorbiae (Hemiptera: Aphididae) population dynamics on three cultivars of tomato
- Creator:
- Rivelli, Anna R., Tritta, Vincenzo, Toma, Irene, Fanti, Paolo, and Battaglia, Donatella
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hemiptera, Aphididae, Macrosiphum euphorbiae, aphid population dynamics, Lycopersicon exculentum, water stress, trophic interaction, 2, and 59
- Language:
- English
- Description:
- 1_Macrosiphum euphorbiae. Three tomato cultivars (Scintilla, Beefmaster and Rio Grande) were used in the experiments. The results for three watering regimes were compared with those of a control, which was well watered every three days: stressed plants received one third of the water supplied to the control over each three-day interval (experiment 1); stressed plants received a gradually decreasing amount of water (100% at the first watering and then 80%, 60%, 50%, 40% and 20%) every three days (experiment 2); stressed plants received the same amount of water as the control but at longer intervals, that is when evident signs of wilting appeared (experiment 3). The results showed that water stress either enhanced, had an adverse effect or had no effect on aphid population growth, depending on the cultivar and watering regime. No difference was recorded in the population dynamics of M. euphorbiae feeding on Beefmaster tomato plants subjected to different levels of water stress. In the case of the cultivar Scintilla, live aphids were less abundant on stressed plants than on well watered ones in experiment 1 and 3 but not in experiment 2., 2_The highest variability in aphid population dynamics on the plants grown under the different water stress protocols was recorded on the cultivar Rio Grande. In experiment 1, the initial peak in aphid numbers was higher on the water stressed plants than on the control and then decreased to lower numbers than on the control. In experiment 2, there were no differences in the numbers of aphids infesting stressed and control plants. In experiment 3, there were fewer aphids on stressed than on control plants after six days, as in experiment 1, but there was no initial peak in aphid numbers., Anna R. Rivelli ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
48. Respiratory metabolism of the pea aphid, Acyrthosiphon pisum (Hemiptera: Aphididae)
- Creator:
- Karel Sláma and Jedlička, Pavel
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hemiptera, Aphididae, Acyrthosiphon pisum, O2 consumption, CO2 “bursts”, discontinuous respiration, respiratory acidaemia, virginoparae, oviparae, 2, and 59
- Language:
- English
- Description:
- 1_The respiratory metabolism of different polyphenic forms of the pea aphid, including wingless and winged asexual females (virginoparae), sexual females (oviparae) and winged or wingless adult males, was investigated using a micro-respirographic method. The records revealed sub-nanoliter amounts per min of O2 consumption or CO2 output. Respiratory metabolism of individuals was monitored for 3 to7 h after removal of the aphid from the food plant. Most of the recordings were for relatively large (3.5 mg), wingless asexual females (virginoparae). These aphids exhibited a continuous and very regular respiratory gas exchange (example: specimen of 3.5 mg body mass consumed 180 nl of O2 per min; released simultaneously 300 nl CO2 per min; = standard metabolic rate of 3085 µl O2 / g / h; R.Q. = 1.66). This continuous pattern of respiration occurred only when the aphids were kept at relatively high humidity. By contrast, aphids of various seasonal forms exhibited discontinuous respiratory gas exchange when kept in relatively dry air (atmospheric, room conditions). These patterns can be briefly described as follows: (a) Short and rather small micro-cycles of CO2 emission, manifested usually by the sudden expiration of 60–120 nl of CO2 once every 5 min; (b) Larger bursts of 240–480 nl of CO2 with a periodicity of one hour; (c) Enormously large, discontinuous bursts of 10–14 µl CO2, duration 10–30 min, repeated with a periodicity of several hours. There was no constant pattern of diffusive CO2 emission (DGC). The aphids exhibited a pattern of CO2 release that was appropriate for the external conditions, such as temperature and humidity, and internal physiological conditions such as metabolic activity, availability of reserve substances (carbohydrate, lipid) and water. Certain stages (wingless virginoparae) exhaled volumes of CO2 greatly in excess of their O2 consumption (R.Q. over 1.5)., 2_Sudden exhalations of CO2 from the body were a consequence of a bulk production and outflow of CO2 and not due to the diffusion of CO2 previously accumulated within the tracheal system. Due to their generally high metabolic activity (1142 to 6780 µl O2 / g / h), aphid tissue and organs produced relatively large amounts of metabolically formed carbonic acid. The resulting respiratory acidaemia was moderated by outbursts of gaseous CO2, liberated from liquid carbonate buffers by a regulatory mechanism based on enzymatic hydration and neutralization of carbonic acid by discontinuous formation of gaseous CO2., Karel Sláma, Pavel Jedlička., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
49. Revision of the Australian genus Blaena (Heteroptera: Cydnidae)
- Creator:
- Lis, Jerzy A. and Joanna , Heyna
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Heteroptera, Cydnidae, Blaena, revision, new species, and Australia
- Language:
- English
- Description:
- A revision of species of the Australian burrower bug genus Blaena Walker, 1868 is presented. Eight previously known species are redescribed and four new ones, B. hirta n. sp. (Queensland), B. parathroposa n. sp. (Queensland), B. pseudosetosa n. sp. (Western Australia), and B. serrata n. sp. (Northern Territory, Queensland, Western Australia) are described and illustrated. The male and female genitalia of all the species of the genus are studied for the first time. A key for species determination is also provided.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
50. Revision of the New Caledonian genus Nobarnus (Hemiptera: Tingidae) with description of three new species
- Creator:
- Guilbert, Eric
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Tingidae, Nobarnus, revision, new species, and New Caledonia
- Language:
- English
- Description:
- Three new species of Tingidae (Tinginae: Tingini) belonging to the New Caledonian endemic genus Nobarnus Distant are described: N. albiceps, N. nigriceps and N. pilosus, N. signatus (Distant) and N. typicus. Distant are redescribed and the status of the genus is discussed and enlarged to accommodate the new species. A table of the main characters distinguishing species and a key to species are given.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public