Search results for "VAS"
showing 10 items of 15144 documents
Adaptive introgression from maize has facilitated the establishment of teosinte as a noxious weed in Europe
2020
Global trade has considerably accelerated biological invasions. The annual tropical teosintes, the closest wild relatives of maize, were recently reported as new agricultural weeds in two European countries, Spain and France. Their prompt settlement under climatic conditions differing drastically from that of their native range indicates rapid genetic evolution. We performed a phenotypic comparison of French and Mexican teosintes under European conditions and showed that only the former could complete their life cycle during maize cropping season. To test the hypothesis that crop-to-wild introgression triggered such rapid adaptation, we used single nucleotide polymorphisms to characterize p…
Citizen science: a successful tool for monitoring invasive alien species (IAS) in Marine Protected Areas. The case study of the Egadi Islands MPA (Ty…
2018
The chief purpose of Marine Protected Areas (MPAs) is biodiversity conservation. The effects that invasive alien species (IAS) have on MPAs, and vice versa, are not yet fully known, even though assessing them is crucial for MPA planning. Management plans require sound knowledge of the pathways of introduction, the impact and current distribution of IAS. Monitoring plans are essential for preventing and reducing the risk of IAS introduction. In this respect, the involvement of citizen scientists in gathering data (validated by taxonomic experts) on the occurrence of IAS, that would otherwise be impossible to collect, may be crucial. We report on our experience of citizen science in the Egadi …
Variation in Hsp70 Levels after Cold Shock: Signs of Evolutionary Responses to Thermal Selection among Leptinotarsa decemlineata Populations
2012
Individuals of widely spread species are expected to show local adaption in temperature tolerance as they encounter a range of thermal conditions. We tracked thermal adaptations of the Colorado potato beetle (Leptinotarsa decemlineata) that invaded Europe within the last 100 years. It has occupied various conditions although, like the majority of invasive species, it lost a measurable amount of neutral genetic variation due to bottleneck effect when it invaded Europe. We exposed diapausing beetles originated from three different latitudes (54°N, 59°N, 60°N) to cold shock (−5°C, 1.5 hrs) in order to test if beetles from the northern populations express differential levels of cold-induced and…
Trophic interactions between introduced lake trout (Salvelinus namaycush) and native Arctic charr (S. alpinus) in a large Fennoscandian subarctic lake
2014
Introduced fishes may have major impacts on community structure and ecosystem function due to competitive and predatory interactions with native species. For example, introduced lake trout (Salvelinus namaycush) has been shown to replace native salmonids and induce major trophic cascades in some North American lakes, but few studies have investigated trophic interactions between lake trout and closely related native Arctic charr (S.alpinus) outside the natural distribution of the former species. We used stomach content and stable isotope analyses to investigate trophic interactions between introduced lake trout and native Arctic charr in large subarctic Lake Inarijarvi in northern Finland. …
Controversy over the Mode of Growth of Cambial Cylinder
2021
Based on mathematical modelling, this review article describes the mechanism of expansion in the circumference of vascular cambium due to radial growth leading to increase in the tree-trunk diameter, and emphasizes upon the huge difference in the rate of symplastic growth of cambial initials in two different directions, viz. radial and circumferential. On the basis of anatomical evidence regarding the role of symplastic and intrusive growths, the long-standing hypothesis that the intrusive growth contributes to the increase of cambium circumference has been falsified. It has been shown with the help of mathematical calculations as well as anatomical observations that only symplastic growth …
Biological control of invasive stink bugs: review of global state and future prospects
2020
International audience; Invasive stink bugs (Hemiptera: Pentatomidae) are responsible for high economic losses to agricul-ture on a global scale. The most important species, dating from recent to old invasions, includeBagrada hilaris (Burmeister), Halyomorpha halys (Stal), Piezodorus guildinii (Westwood), Nezara vir-idula (L.), and Murgantia histrionica (Hahn). Bagrada hilaris, H. halys,andN. viridula are nowalmost globally distributed. Biological control of these pests faces a complex set of challenges thatmust be addressed to maintain pest populations below the economic injury level. Several case studiesof classical and conservation biological control of invasive stink bugs are reported …
Stress for invasion success? Temperature stress of preceding generations modifies the response to insecticide stress in an invasive pest insect
2012
Adaptation to stressful environments is one important factor influencing species invasion success. Tolerance to one stress may be complicated by exposure to other stressors experienced by the preceding generations. We studied whether parental temperature stress affects tolerance to insecticide in the invasive Colorado potato beetle Leptinotarsa decemlineata. Field-collected pyrethroid-resistant beetles were reared under either stressful (17°C) or favourable (23°C) insecticide-free environments for three generations. Then, larvae were exposed to pyrethroid insecticides in common garden conditions (23°C). Beetles were in general tolerant to stress. The parental temperature stress alone affect…
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…
PERSPECTIVE: Underutilized resources for studying the evolution of invasive species during their introduction, establishment, and lag phases
2010
The early phases of biological invasions are poorly understood. In particular, during the introduction, establishment, and possible lag phases, it is unclear to what extent evolution must take place for an introduced species to transition from established to expanding. In this study, we highlight three disparate data sources that can provide insights into evolutionary processes associated with invasion success: biological control organisms, horticultural introductions, and natural history collections. All three data sources potentially provide introduction dates, information about source populations, and genetic and morphological samples at different time points along the invasion trajector…
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…