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12. Convergent photoperiodic plasticity in developmental rate in two species of insects with widely different thermal phenotypes
- Creator:
- Kutcherov, Dmitry, Lopatina, Elena B, and Balashov, Sergei
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- polokřídlí, brouci, mandelinkovití, fotoperiodismus, teplota, Hemiptera, beetles, Chrysomelidae, photoperiodism, temperature, Pyrrhocoridae, Scantius aegyptius, Coleoptera, Timarcha tenebricosa, body size, development, reaction norm, seasonality, 2, and 59
- Language:
- English
- Description:
- Growth and development rates in many insects are affected by photoperiod, which enables insects to synchronize their life histories with seasonal events, but this aspect of insect photoperiodism remains understudied. Here we use several experimental combinations of constant day length and temperature to determine whether there are quantitative developmental responses to photoperiod in the bug Scantius aegyptius and leaf beetle Timarcha tenebricosa. The thermal ecology of these two species is strikingly different: the former is thermophilic and active throughout summer and the latter is spring-active and avoids the hottest time of the year. In accordance with their contrasting natural thermal environments, S. aegyptius survives better and achieves a larger final body mass at the high experimental temperatures, while T. tenebricosa survives better and is heavier at the low experimental temperatures. Despite this polarity, long-day conditions accelerate larval development relative to a short-day photoperiod in both species, and this developmental response is stronger at low temperatures. Our re-visitation of previous literature in light of the new findings indicates that this similarity in photoperiodic response is superficial and that relatively faster development in midsummer is likely to have a different ecological role in summer- and spring-active species. In the former, it may allow completion of an additional generation during the favourable season, whereas in the latter, this acceleration likely ensures that the larval stage, which is vulnerable to heat, is completed before the onset of hot weather., Dmitry Kutcherov, Elena B. Lopatina, Sergei Balashov., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
13. Detection of telomeric sequences and ribosomal RNA genes in holokinetic chromosomes of five jumping plant-lice species: First data on the superfamily Psylloidea (Hemiptera: Sternorrhyncha)
- Creator:
- Maryańska-Nadachowska, Anna, Kuznetsova, Valentina G, Golub, Natalia V, and Anokhin, Boris A
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- polokřídlí, mšicosaví, mery, merovití, Hemiptera, Sternorrhyncha, Psylloidea, Psyllidae, Aphalaridae, telomeric repeats, 18S rDNA, FISH, NOR, 2, and 59
- Language:
- English
- Description:
- Fluorescence in situ hybridization (FISH) is a technique used to determine the chromosomal position of DNA and RNA probes. The present study contributes to knowledge on jumping plant-lice genomes by using FISH with 18S rDNA and telomeric (TTAGG)n probes on meiotic chromosomes of Psylla alni (2n = 24 + X), Cacopsylla mali (2n = 22 + neo-XY and 20 + neo-X1X2Y), C. sorbi (2n = 20 + neo-XY), Baeopelma foersteri (2n = 14 + X), and Rhinocola aceris (2n = 10 + X). This is the first study that has used FISH on the hemipteran superfamily Psylloidea. We found that the chromosomes of all studied species contain the insect-type telomere motif, (TTAGG)n. In C. mali and C. sorbi, the neo-sex chromosomes originating from autosome-sex chromosome fusions showed no interstitially located clusters of TTAGG repeats, suggesting their loss or inactivation. Similarly, no interstitial (TTAGG)n clusters were detected in an extremely large autosome pair of B. foersteri that most likely originated from a fusion of at least five ancestral chromosome pairs. Clusters of 18S rDNA were detected on the fused and second largest autosome pairs of B. foersteri and on one of the large autosome pairs of the remaining species. In C. mali and B. foersteri, the rDNA clusters were shown to coincide with the NORs as detected by the AgNOR method. Finally, we speculate, based on the obtained FISH markers, on the mechanisms of karyotype evolution of psylloid species differing in chromosome numbers and sex chromosome systems., Anna Maryańska-Nadachowska, Valentina G. Kuznetsova, Natalia V. Golub, Boris A. Anokhin., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14. 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
15. Do the arthropod communities on a parasitic plant and its hosts differ?
- Creator:
- Lázaro-González, Alba, Hódar, José A., and Zamora, Regino
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, jmelí bílé, borovice, polokřídlí, Viscum album, Pinus, Hemiptera, Mistletoe, hemiparasitic plant, pine host, arthropod communities, specialist insect, Cacopsylla visci, Pinalitus viscicola, Anthocoris visci, 2, and 59
- Language:
- English
- Description:
- Parasitic plants growing on tree branches may be a novel niche and phytoresource for arthropods. The spatial continuity between hosts and their parasites in canopies might provide a homogeneous environment for arthropod communities, but differences in mistletoe leaves and host needles could be exploited by different species of arthropods. Therefore, it is important to determine insect-community assemblages in order to discover the role of parasitic plants as a different habitat for arthropods. Thus, we aim to evaluate the level of similarity between the arthropod community on mistletoe (Viscum album) and that on its two principal pine hosts, Black pine (Pinus nigra) and Scots pine (P. sylvestris), on a Mediterranean mountain. Our results reveal that, irrespective of the species of pine host, V. album has a stable, independent and simple arthropod trophic web, composed mainly of two specialist hemipteran herbivores, Cacopsylla visci (Psyllidae) and Pinalitus viscicola (Miridae), and a hemipteran predator, Anthocoris visci (Anthocoridae). Despite this, the composition of the arthropod communities differed significantly on both host species, with a greater richness and diversity on Scots than Black pine and these differences are not reflected in the community on mistletoe. Overall, we conclude that, although Viscum album is considered to be a pest of pine, its presence increases the heterogeneity of the forest canopy by providing a novel habitat for a new and specific community of arthropods. In addition, this is a new record for and most probably an extension of the southernmost limit of the known geographical distribution of the arthropod community inhabiting V. album., Alba Lázaro-González, José A. Hódar, Regino Zamora., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
16. Eastern Arc Mountains in Tanzania: hic sunt Aenictopecheidae. The first genus and species of Afrotropical Aenictopecheidae (Hemiptera: Heteroptera: Enicocephalomorpha)
- Creator:
- Pavel Štys and Baňař, Petr
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hemiptera, Heteroptera, Enicocephalomorpha, Aenictopecheidae, Ulugurocoris grebennikovi gen. n. et sp. n., taxonomy, morphology, distribution, epimeroid (new term), true bug, Afrotropical region, Tanzania, Eastern Arc Mountains, 2, and 59
- Language:
- English
- Description:
- A new genus and species of Hemiptera: Heteroptera: Enicocephalomorpha: Aenictopecheidae: Aenictopecheinae, Ulugurocoris grebennikovi gen. et sp. n., based on micropterous females from Tanzania, Uluguru Mts, Budunki, is described and differentiated. The males are probably macropterous. Some general aspects of morphology of U. grebennikovi are discussed in a broader context, such as presence of cephalic trichobothria (suggested to be a groundplan character of Heteroptera), presence of “gular sulci” (suggested to have an ecdysial function), lack of cephalic neck (symplesiomorphy with other Hemiptera), presence of posterior lobe of pronotum associated with the epimeroid (a new term for so called “proepimeral lobe”), and presence of notopleural sulcus on the propleuron. Diagnostic characters of the Aenictopecheinae are summarized and distribution of their seven genera is reviewed. Ulugurocoris grebennikovi is the first representative of the basal family Aenictopecheidae in the Afrotropical Region. The type locality is situated in the Eastern Arc Mountains (Tanzania), a recently identified hotspot of Afrotropical diversity characterized by a high degree of endemism caused by high rates of speciation combined with low rates of extinction. A brief characterization of the area is provided., Pavel Štys, Petr Baňař., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
17. Effect of ant attendance on aphid population growth and above ground biomass of the aphid's host plant
- Creator:
- Hosseini, Afsane, Hosseini, Mojtaba, Katayama, Noboru, and Mehrparvar, Mohsen
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, polokřídlí, mšicovití, blanokřídlí, populační růst, Hemiptera, Aphididae, Hymenoptera, population growth, Formicidae, ant-aphid interaction, aphid performance, developmental stage, plant yield, 2, and 59
- Language:
- English
- Description:
- Ant-aphid mutualism is considered to be a beneficial association for the individuals concerned. The population and fitness of aphids affected by ant attendance and the outcome of this relationship affects the host plant of the aphid. The main hypothesis of the current study is that ant tending decreases aphid developmental time and/or increases reproduction per capita, which seriously reduces host plant fitness. The effect of attendance by the ant Tapinoma erraticum (Latreille, 1798) (Hymenoptera: Formicidae) on population growth and duration of different developmental stages of Aphis gossypii Glover (Hemiptera: Aphididae) were determined along with the consequences for the fitness of the host plant of the aphid, Vicia faba L., in greenhouse conditions. The initial aphid density was manipulated in order to study aphid performance due to density-dependent changes in ant attendance. The population growth rate of ant attended aphids was more than that of unattended aphids. However, the ratio of 1st-2nd nymphs to adults in aphid populations attended by ants was lower. The yields of bean plants on which the aphids were attended by ants were significantly greater than those of unattended plants. This study indicates that ants not only increase aphid fitness in terms of their population growth rate, but also benefit the host plant., Afsane Hosseini, Mojtaba Hosseini, Noboru Katayama, Mohsen Mehrparvar., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
18. Effect of female size on host selection by a koinobiont insect parasitoid (Hymenoptera: Braconidae: Aphidiinae)
- Creator:
- Lykouressis, Dionyssios, Garantonakis, Nikolaos, Perdikis, Dionyssios, Fantinou, Argyro, and Mauromoustakos, Andronikos
- Type:
- article, model:article, and TEXT
- Subject:
- Hymenoptera, Braconidae, Aphidius colemani, Hemiptera, Aphis gossypii, Myzus persicae, aphid, body size, and host selection
- Language:
- English
- Description:
- Body size is a main fitness component of insect parasitoids. We assessed the potential influence of maternal size of the parasitoid wasp Aphidius colemani Viereck (Hymenoptera: Braconidae: Aphidiinae) on its ability to parasitize the different instars of Aphis gossypii Glover (Hemiptera: Aphididae) on eggplant and cucumber. In the experiments "small" vs "large" parasitoid females were used. Females oviposited in all instars but more of the smaller hosts were parasitized. Host selection was affected by female size and the larger hosts were more frequently mummified by the large than the small females. Thus, parasitoid female size influenced host selection. This could affect the potential of the parasitoid to exploit populations of aphids that differ in their size structure. The importance of these results in terms of the ecological adaptations of the parasitoid and their implication for biological control are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
19. Effect of temperature on the interaction between Chrysoperla externa (Neuroptera: Chrysopidae) and Sipha flava (Hemiptera: Aphididae)
- Creator:
- Oliveira, Simone A., Auad, Alexander M., Souza, Brigida, Silva , Danieal M. , and Carvalho, Caio A.
- Type:
- article, model:article, and TEXT
- Subject:
- Neuroptera, Chrysopidae, Chrysoperla externa, Hemiptera, Aphididae, Sipha flava, aphids, green lacewing, predator, and biological control
- Language:
- English
- Description:
- This paper examines some biological aspects and the predatory capacity of Chrysoperla externa fed nymphs of Sipha flava and reared at different temperatures. Recently hatched larvae were placed individually in Petri dishes, fed ad libitum with S. flava and reared at either 12, 16, 20, 24, 28 or 32 ± 1°C, a RH of 70 ± 10% and a 12-h photophase. The experiment was fully randomized with 30 replicates of each treatment. The duration and survival in each instar, and larval and pupal stages (pre-pupa + pupa) were analyzed. To determine the predatory capacity of larvae they were each provided daily with three-day-old nymphs of the aphid, in a number greater than they could consume. Ninety C. externa larvae were kept individually in Petri dishes at 24 ± 1°C, and their daily consumption recorded during development. Temperature influenced the rate of larval and pupal development. There was a decrease in the duration of development with increase in temperature. Regression analyses, based on quadratic equations, were used to describe the effect of temperature on the duration of development in the different instars of C. externa. This revealed that the base temperature increased as the larvae developed towards the adult phase. The survival of larvae in the first and second instars was similar at 12, 16, 20, 24, 28 and 32°C but none of the third instar larvae completed their development at 12°C and 32°C. The average daily and total consumption of aphids by third instar larvae was about 48 times greater than that of first instar larvae. The larvae ate an average of 10, 37 and 479 aphids in the first, second and third instars, respectively.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
20. Experimental evidence for competitive exclusion of Myzus persicae nicotianae by Myzus persicae s.s. (Hemiptera: Aphididae) on sweet pepper, Capsicum annuum (Solanaceae)
- Creator:
- Tapia, Daniel H., Troncoso, Alejandra J., Vargas, Renzo R. , Olivares-Donoso, Ruby, and Niemeyer, Hermann M.
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Aphididae, competition, phytophagous insects, replacement series, green peach aphid, tobacco aphid, bottom-up effects, and competitive displacement
- Language:
- English
- Description:
- The importance of interspecific competition as a force promoting specialization in phytophagous insects has been long debated. Myzus persicae sensu stricto (Hemiptera: Aphididae) is one of the most polyphagous aphids. Its subspecies, M. persicae nicotianae, is found mainly on tobacco, although it can survive and reproduce on a relatively wide range of plant species in the laboratory. Since life history traits of these taxa make competitive interactions likely, we hypothesize that asymmetrical competition occurs between M. p. nicotianae and M. persicae s.s., and accounts for the exclusion of the former when they share a common resource. This hypothesis was tested in laboratory experiments, which examined the population growth of colonies of both taxa coexisting on sweet pepper. A replacement series experiment was set up with both aphid taxa on sweet pepper plants, and the rates of population growth (RPG) evaluated at 5 day intervals for 25 days. M. p. nicotianae showed a significantly lower RPG when interacting with M. persicae s.s. than when in monotypic colonies, while M. persicae s.s. RPG was unaffected by competition. The relative population growth from the second census onwards of M. persicae s.s. was consistently higher than that of M. p. nicotianae. Finally, the RPG of M. p. nicotianae was significantly reduced when the plant was infested with M. persicae s.s. The results suggest that the absence of M. p. nicotianae from sweet pepper in the field in Chile can be partly explained by competitive exclusion by M. persicae s.s.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public