Search

Start Over Subject 59 Harvested from CDK

862. Warp-speed adaptation to novel hosts after 300 generations of enforced dietary specialisation in the seed beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)

Creator:
Price, Thomas N., Leonard, Aoife, and Lancaster, Lesley T.
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, brouci, mandelinkovití, beetles, Chrysomelidae, Coleoptera, Bruchinae, Callosobruchus maculatus, emerging crop pests, host shifts, genetic variation, adaptation trajectory, evolvability, experimental evolution, quasi-natural selection, heritability, 2, and 59
Language:
English
Description:
Herbivorous insects are often highly specialised, likely due to trade-offs in fitness on alternative host species. However, some pest insects are extremely adaptable and readily adopt novel hosts, sometimes causing rapid expansion of their host range as they spread from their original host and geographic origin. The genetic basis of this phenomenon is poorly understood, limiting our ability to predict or mitigate global insect pest outbreaks. We investigated the trajectory of early adaptation to novel hosts in a regionally-specialised global crop pest species (the cowpea seed beetle Callosobruchus maculatus). After experimentally-enforced dietary specialisation for nearly 300 generations, we measured changes in fitness over the first 5 generations of adaptation to 6 novel hosts. Of these, C. maculatus reproduced successfully on all but one, with reduced fitness observed on three hosts in the first generation. Loss of fitness was followed by very rapid, decelerating increases in fitness over the first 1-5 generations, resulting in comparable levels of population fitness to that observed on the original host after 5 generations. Heritability of fitness on novel hosts was high. Adaptation occurred primarily via changes in behavioural and phenological traits, and never via changes in offspring survival to adulthood, despite high heritability for this trait. These results suggest that C. maculatus possesses ample additive genetic variation for very rapid host shifts, despite a prolonged period of enforced specialization, and also suggest that some previously-inferred environmental maternal effects on host use may in part actually represent (rapidly) evolved changes. We highlight the need to examine in more detail the genetic architecture facilitating retention of high additive genetic variation for host shifts in extremely adaptable global crop pests., Thomas N. Price, Aoife Leonard, Lesley T. Lancaster., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

863. Weather-dependent fluctuations in the abundance of the oak processionary moth, Thaumetopoea processionea (Lepidoptera: Notodontidae)

Creator:
Csóka, György, Hirka, Anikó, Szöcs, Levente, Móricz, Norbert, Rasztovits, Ervin, and Pödör, Zoltán
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
motýli, dolování dat, butterflies, data mining, Lepidoptera, Notodontidae, Thaumetopoea processionea, light trap, population fluctuation, Moran-effect, drought, oak defoliator, CReMIT-analysis, 2, and 59
Language:
English
Description:
Population fluctuations of the well-known oak defoliator, the oak processionary moth (Thaumetopoea processionea L.), were studied using light trap data and basic meteorological parameters (monthly average temperatures, and precipitation) at three locations in Western Hungary over a period of 15 years (1988-2012). The fluctuations in the numbers caught by the three traps were strongly synchronized. One possible explanation for this synchrony may be similar weather at the three trapping locations. Cyclic Reverse Moving Interval Techniques (CReMIT) were used to define the period of time in a year that most strongly influences the catches. For this period, we defined a species specific aridity index for Thaumetopoea processionea (THAU-index). This index explains 54.8-68.9% of the variation in the yearly catches, which indicates that aridity, particularly in the May-July period was the major determinant of population fluctuations. Our results predict an increasing future risk of Oak Processionary Moth (OPM) outbreaks and further spread if the frequency of severe spring/summer droughts increases with global warming., György Csóka, Anikó Hirka, Levente Szöcs, Norbert Móricz, Ervin Rasztovits, Zoltán Pödör., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

864. Wenyonia gracilis sp. n. (Cestoda: Caryophyllidea) from Synodontis zambezensis (Siluriformes: Mochokidae): the first native caryophyllidean tapeworm from southern Africa

Creator:
Schaeffner, Bjoern C, Rooyen, Divan van, Gerber, Ruan, Scholz, Tomáš, and Smit, Nico J
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
tasemnice, biodiverzita, biogeografie, tapeworms, biodiversity, biogeography, Afrika jižní, Africa, Southern, fish parasites, new species, molecular characterisation, taxonomy, 2, and 59
Language:
English
Description:
Parasitological examination of freshwater fishes of the Phongolo River in north-eastern KwaZulu-Natal, South Africa resulted in the discovery and morphological and molecular characterisation of a new species of Wenyonia Woodland, 1923 (Cestoda: Caryophyllidea). The new species from the plain squeaker, Synodontis zambezensis Peters (Siluriformes: Mochokidae), is morphologically most similar to Wenyonia acuminata Woodland, 1923, a species reported from three species of Synodontis in north-eastern, western and central Africa (Sudan, Nigeria, Democratic Republic of the Congo). Both these species are markedly different from congeners by having a nematoform body and a digitiform scolex. Wenyonia gracilis sp. n. differs from W. acuminata in its general body size, length and width of main body regions (testicular and uterine regions), a posterior extension of the testes into the uterine region, numerous postovarian vitelline follicles filling the entire medulla, eggs c. 1/3 larger in size, and a scolex with an apical introvert but devoid of longitudinal furrows and a well-defined base. Wenyonia gracilis is the seventh species in the genus and the first autochthonous caryophyllidean ever reported and described from southern Africa (south of the Zambezi River)., Bjoern C. Schaeffner, Divan van Rooyen, Ruan Gerber, Tomáš Scholz, Nico J. Smit., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

865. When landscape variables do not explain migration rates: An example from an endangered dragonfly, Leucorrhinia caudalis (Odonata: Libellulidae)

Creator:
Bolliger, Janine, Keller, Daniela, and Holderegger, Rolf
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, entomologie, Švýcarsko, Switzerland, Odonata, Leucorrhinia caudalis, assignment test, BIMR, contemporary gene flow, landscape genetics, microsatellites, 2, and 59
Language:
English
Description:
Leucorrhinia caudalis is a dragonfly species threatened throughout Europe. Despite evidence of the recent extension of its distribution range, it is unknown whether L. caudalis regularly or hardly ever migrates among ponds. The contemporary migration patterns of the species were investigated using Bayesian assignment tests and the migration rates related to landscape structural and thematic variables (distance between ponds, forest area, area of water body, area of hedgerow). Migration rates of L. caudalis are independent of any landscape element. Thus, landscape structure is not a barrier or corridor for migration in this species. The tendency of L. caudalis to disperse is largely independent of the nature of the landscape, at least at the scale of the present study. and Janine Bolliger, Daniela Keller, Rolf Holderegger.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

866. White plant shoots, wax-producing insects and other white structures made by arthropods: a mimicry complex?

Creator:
Yamazaki, Kazuo
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, vosky, pavouci, waxes, spiders, plant mimicry, anti-herbivore defence, cocoon, entomopathogenic fungus, spider egg sac, spittlebug froth, trichome, 2, and 59
Language:
English
Description:
Many insects masquerade as parts of plants, such as bark or leaves, or mimic poisonous organisms in order to defend themselves against predators. However, recent studies indicate that plants may mimic insects and other arthropods to deter herbivores. Here, I report visually similar white structures of plants and arthropods in Japan and suggest they are part of a mimicry complex. Young shoots covered with white trichomes or waxy substances may mimic wax-producing insects, such as woolly aphids, coccids and caterpillars, potentially resulting in reduced herbivory. Since wax-producing insects would reduce plant quality and quantity, be distasteful and attract natural enemies, herbivorous insects and mammals may avoid such white shoots. Furthermore, fungus-infected insects, gregarious braconid cocoons, spider egg sacs and froth made by froghopper nymphs or blasticotomid sawfly larvae are also conspicuously white and impose risks for herbivorous insects. Thus, these white structures may be mimicry models for white shoots and are likely to be part of a defensive mimicry complex. Although this study focuses on defence against herbivores, there are simultaneous physiological roles for white colouration that will not be discussed in depth here., Kazuo Yamazaki., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

867. Wing morphometric variability of the malaria vector Anopheles (Cellia) epiroticus Linton et Harbach (Diptera: Culicidae) for the duration of the rainy season in coastal areas of Samut Songkhram, Thailand

Creator:
Chaiphongpachara, Tanawat and Laojun, Sedthapong
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
mikroevoluce, microevolution, Thajsko, Thailand, Mosquito, coastal environment, morphological variability, geometric morphometrics, 2, and 59
Language:
English
Description:
In Thailand, Anopheles (Cellia) epiroticus Linton et Harbach (Diptera: Culicidae) is the secondary vector of human malaria along coastal regions. While there are some studies of phenotypic variability and population structure of A. epiroticus, more information on morphological variation would enhance epidemiological understanding of medically important mosquito vectors. This research examined morphological variation at three different distances from coastlines of Samut Songkhram Province, Thailand, using landmark-based geometric morphometrics. Wing shape of A. epiroticus was significantly different in the area 0.2 km away from the sea compared to areas 2 and 4 km away from the sea (p < 0.05). Phenotypic variability in wing shape is associated with distance from the sea. Morphological variations in the area closest to the sea were most pronounced, showing a relationship between A. epiroticus and the ecosystem that affects wing geometry. These results provide important information to understand morphological variation of A. epiroticus in coastal areas., Tanawat Chaiphongpachara and Sedthapong Laojun., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

868. Wolbachia infection in Trissolcus species (Hymenoptera: Scelionidae)

Creator:
Guz, Nurper, Kocak, Erhan, Akpinar, A. Emre, Gurkan, M. Oktay, and Kilinger, A. Neset
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Hymenoptera, Scelionidae, Wolbachia, Trissolcus, sunn pest, biological control, 2, and 59
Language:
English
Description:
Wolbachia is a maternally transmitted intracellular symbiont which causes reproductive distortions in the arthropods it infects. In recent years there has been an increasing interest in using Wolbachia as a potential tool for biological control by genetic manipulation of insect pests. In the present paper we report Wolbachia infection in several Trissolcus wasps (Hymenoptera: Scelionidae) which are important egg parasitoids of the sunn pest, Eurygaster integriceps Puton (Heteroptera: Scutellaridae). We used DNA sequence data for a gene encoding a surface protein of Wolbachia (wsp) not only to confirm Wolbachia infection but also to discriminate Wolbachia strains. Phylogenetic analyses indicated that Wolbachia strains in Trissolcus species were closely related to one another and belonged to supergroup B. Determination of the infection status of various populations, the possible role of Wolbachia in causing the incompatibility and knowledge of the reproductive compatibility of Trissolcus populations is important for the success of parasitoids in sunn pest management., Nurper Guz ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

Limit your search

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

View distribution

Current results range from 1718 to 1946

View larger »