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262. 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
263. Polyphagous predatory rove beetles (Coleoptera: Staphylinidae) induce winged morphs in the pea aphid Acyrthosiphon pisum (Hemiptera: Aphididae)
- Creator:
- Balog, Adalbert, Mehrparvar, Mohsen, and Weisser, Woflgang W.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Staphylinidae, Drusilla canaliculata, Tachyporus hypnorum, Aphididae, Acyrthosiphon pisum, aphid polyphenism, predator-prey interaction, rove beetles, maternal effects, induced defence, 2, and 59
- Language:
- English
- Description:
- A number of aphid species have been shown to produce winged dispersal morphs in the presence of natural enemies. Previous studies tested specialized aphid predators such as ladybirds or lacewing larvae. We confronted colonies of pea aphids with the polyphagous rove beetles, Drusilla canaliculata and Tachyporus hypnorum. For both predators we found that the percentage of winged morphs increased in predator-attacked pea aphid colonies compared to a control. The behaviour of the two rove beetles species was noticeably different. D. canaliculata mostly foraged on the ground and rarely on the plant, while T. hypnorum was almost exclusively observed on the plants, causing a higher number of aphids to drop to the ground, which resulted in a stronger increase in winged morph production. Our results clearly show that not only monophagous aphid predators but also more polyphagous insect predators, which include aphids in their diet, can induce aphids to produce winged morphs., Adalbert Balog, Mohsen Mehrparvar, Wolfgang W. Weisser., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
264. Population dynamics, seasonality and aphid prey of Cheilomenes sexmaculata (Coleoptera: Coccinellidae) in an urban park in central Japan
- Creator:
- Kawakami, Yasuko, Yamazaki, Kazuo, and Ohashi, Kazunori
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, mšice, beetles, Coccinellidae, aphids, Coleoptera, Cheilomenes sexmaculata, climate conditions, ladybird beetle, life cycle, urban vegetation, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
265. Population structures of three Calliptamus spp. (Orthoptera: Acrididae) across the Western Mediterranean Basin
- Creator:
- Lecoq, Michel, Sword, Gregory A., Pages, Christine, Bondin, Laurence, Billot, Claire, Rivallan, Ronan, Foucart, Antoine, Vassal, Jean-Michel, Risterucci, Ange-Marie, and Chapuis, Marie-Pierre
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Orthoptera, Acrididae, Calliptamus, population genetic, microsatellite, closely related species, potential pests, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
266. Praon volucre (Hymenoptera: Braconidae: Aphidiinae), a natural enemy of Macrosiphum euphorbiae (Hemiptera: Aphididae): Life table and intrinsic rate of population increase
- Creator:
- Lins jr., Juracy Caldeira, Bueno, Vanda Helena Paes, Silva, Diego Bastos, Sampaio, Marcus Vinicius, and van Lenteren, Joop C.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Aphididae, Macrosiphum euphorbiae, Braconidae, Praon volucre, parasitoid, fecundity, immature mortality, developmental time, biological control, intrinsic rate of population increase, 2, and 59
- Language:
- English
- Description:
- 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.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
267. Pre- and post-parturial aspects of scorpion reproduction: a review
- Creator:
- Warburg, Michael R.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Scorpiones, fertilization, insemination, gestation, parturition, birth, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
268. 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
269. Preference of larvae of Enallagma cyathigerum (Odonata: Coenagrionidae) for habitats of varying structural complexity
- Creator:
- Verdonschot, Ralf C.M. and Peeters, Edwin T.H.M
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Enallagma cyathigerum, habitat complexity, macroinvertebrate-macrophyte interaction, Zygoptera, phytomacrofauna, two-choice experiment, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
270. Preliminary evidence of the horizontal transmission of Wolbachia between Crioceris leaf beetles (Coleoptera: Chrysomelidae) and their Asparagus host plants
- Creator:
- Kolasa, Michał, Montagna, Matteo, Mereghetti, Valeria, Daniel Kubisz, Mazur, Miłosz A., and Kajtoch, Łukasz
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, mandelinkovití, chřest, molekulární ekologie, beetles, Chrysomelidae, asparagus, molecular ecology, Alpha-Proteobacteria, Wolbachia, Crioceris, Coleoptera, horizontal transmission, Multilocus Sequence Typing, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public