Search results for "Insect Science"
showing 10 items of 1011 documents
Scent of Jasmine Attracts Alien Invaders and Records on Citizen Science Platforms: Multiple Introductions of the Invasive Lacebug Corythauma ayyari (…
2020
Simple Summary The distribution of the lacebug Corythauma ayyari, a pest species associated to jasmine plants, has been updated using collections and citizen-science data. The path of introduction of this species in Italy has been inferred with molecular analysis. The results revealed an extent of occurrence in Italy wider than was previously known and the evidence of multiple introduction events. The work shows that citizen science can represent a further tool within the early warning information system for alien species introduction. Abstract The jasmine lacebug Corythauma ayyari is a pest of cultivated and ornamental plants mainly associated to Jasminum spp. This invasive insect is nativ…
Do carotenoid-based sexual traits signal the availability of non-pigmentary antioxidants?
2006
SUMMARY Carotenoid-based signals are thought to be indicators of male quality because they must be obtained from the diet and might thus indicate the ability of individuals to gather high-quality food. However, carotenoids are also known to have important physiological functions as immunoenhancers and antioxidants, and, as such, carotenoid-based sexual traits have also been suggested to reflect the health and antioxidant status of their bearers. This last idea is based on the hypothesis that carotenoids that are allocated to sexual signals are no longer available for the detoxification system. Recently, this hypothesis has been challenged on the grounds that the antioxidant activity is not …
World-wide variation in Drosophila melanogaster sex pheromone: behavioural effects, genetic bases and potential evolutionary consequences
1996
0016-6707 (Print) Journal Article Research Support, Non-U.S. Gov't; In Drosophila melanogaster, male wing vibration, a key element of courtship behaviour, is most efficiently induced by a female-specific contact pheromone cis, cis 7,11 heptacosadiene (7,11 HD), which is the main mature female cuticular hydrocarbon in the CS laboratory strain. A study of 63 strains from around the world revealed that flies from Sub-Saharan Africa and the Caribbean are unique in showing low levels 7,11 HD and high levels of the position isomer 5,9 HD. This difference maps to chromosome III, perhaps indicating a simple genetic control of the 7,11 HD:5,9 HD ratio. Females from strains with high levels of 7,11 H…
Investigation of deltamethrin resistance in salmon lice (Lepeophtheirus salmonis) provides no evidence for roles of mutations in voltage-gated sodium…
2020
BACKGROUND The pyrethroid deltamethrin is used to treat infestations of farmed salmon by parasitic salmon lice, Lepeophtheirus salmonis (Kroyer). However, the efficacy of deltamethrin for salmon delousing is threatened by resistance development. In terrestrial arthropods, knockdown resistance (kdr) mutations of the voltage-gated sodium channel (Nav ), the molecular target for pyrethroids, can cause deltamethrin resistance. A putative kdr mutation of an L. salmonis sodium channel homologue (LsNav 1.3 I936V) has been identified previously. At the same time, deltamethrin resistance of L. salmonis has been shown to be inherited maternally and to be associated with mitochondrial DNA (mtDNA) muta…
Habitat Preference of German Mantis religiosa Populations (Mantodea: Mantidae) and Implications for Conservation.
2015
In Germany, the thermophilic European mantid ( Mantis religiosa L.) is endangered. Here, we study habitat requirements during its life, and discuss the applicability of the two conservation measures grazing and mowing to this insect species . At two study sites in south-western Germany, which were each subject to one of these measures, we recorded structural and climatic conditions within different microhabitats. We also conducted capture–mark–recapture studies for adult M. religiosa , and mapped adult roosting, oothecae deposition, egg hatching, and imaginal molting in microhabitats over two vegetation periods. In order to assess microhabitat preference of M. religiosa during its life, and…
Reproductive site selection: evidence of an oviposition cue in a highly adaptive dipteran, Drosophila suzukii (Diptera: Drosophilidae)
2020
Abstract Drosophila suzukii (Matsumura) is a vinegar fly species that originates from Eastern Asia and has spread throughout Europe and the Americas since its initial detection in United States in 2008. Its relatively large, sclerotized, and serrated ovipositor enables the ability to penetrate ripening fruits, providing a protected environment for its egg and larval stages. Because the mechanism of oviposition site selection of D. suzukii is a matter of hypothesis, the aim of the present study was to elucidate behavioral and chemical aspects of short-range ovipositional site selection within the context of D. suzukii reproductive biology. The preference of D. suzukii to lay eggs on artifici…
No inbreeding depression in sperm storage ability or offspring viability in Drosophila melanogaster females.
2013
Mating between relatives usually decreases genetic quality of progeny as deleterious recessive alleles are expressed in inbred individuals. Inbreeding degrades sperm traits but its effects on sperm storage and fate within females are currently unknown. We quantified the relationship between the degrees of inbreeding relevant to natural populations (f=0, 0.25 and 0.50) and the number of sperm inseminated and stored, sperm swimming speed, long-term sperm viability while in storage, pattern of sperm precedence, mating latency, and offspring viability of female Drosophila melanogaster. The use of transgenic flies that have either red or green fluorescent sperm heads allowed us to distinguish tw…
Dynamics of PHA-induced immune response and plasma carotenoids in birds: should we have a closer look?
2009
SUMMARY Allocation trade-offs of limited resources are thought to ensure the honesty of sexual signals and are often studied using controlled immune challenges. One such trade-off between immunity and ornaments is that involving carotenoids. Phytohemagglutinin (PHA)-induced immune response is a widely used immune challenge, yet more details on the underlying physiological mechanisms and potential costs are needed. We investigated the temporal dynamics of PHA-induced immune response and associated changes in blood carotenoids, body mass and a carotenoid-based coloured signal. We found variation in individual response patterns to PHA after peak swelling was reached, with birds showing either …
Elevated oxidative stress in pied flycatcher nestlings of eumelanic foster fathers under low rearing temperatures
2019
Striking variation in melanin coloration within natural populations is likely due to the different fitness outcomes of alternative phenotypes in varying environmental conditions. There are two types of melanin: eumelanins yield blackish hues, whereas pheomelanins yield reddish hues. The production of eumelanins requires low levels of glutathione (GSH), which is the most important intracellular antioxidant, whereas the production of pheomelanins requires high levels of GSH. We investigated the oxidative status of male pied flycatchers (Ficedula hypoleuca) with different degrees of melanin coloration under different temperatures during the nestling period. Moreover, we assessed the oxidative …
New Mediterranean records of Trabutina mannipara (Hemprich & Ehrenberg 1829) (Hemiptera: Coccomorpha: Pseudococcidae)
2018
The occurrence of Trabutina mannipara (Hemprich & Ehrenberg, 1829) (Hemiptera: Coccomorpha) is reported for the first time at Linosa (Pelagian Islands, Sicily Channel, Italy) and Libya. T. mannipara was approved by USA authorities for release as biocontrol agents against invasive saltcedars. The potential impact of this species, that in the Mediterranean area showed to be occasionally invasive, is discussed.