Search results for "Insect pest"
showing 10 items of 15 documents
Alien Insect Impact on Cultural Heritage and Landscape: an Underestimated Problem
2017
The impact of alien invasive insects on cultural heritage and landscapes is very often neglected; even though, more than 50% of species that threaten cultural heritage in Europe are of exotic origin. In addition they are more aggressive. Several examples and a description, are given of the most dangerous alien insects present in heritage sites that constitute a risk for the conservation of cultural property: museum collections, libraries, archives and historic buildings. Globalisation has increased this phenomenon but traces of the accidental introduction of insect pests have occurred since Roman times. The paper discusses the need to implement an estimation of the costs that arise from the…
What does happen when an insect pest follows its host plant and viceversa?
2015
Invasive species are usually well known but only make up a small percentage of the European’s alien plants and insects. The ways these exotic species interact with our natural and cultural heritage are very complex and even some species considered invasive had and could have positive aspects on some European landscape and culture. A close look at the complicated relationship between non-native and native plants and insects in the Mediterranean areas reveals some unexpected twists in the story. Here are some cases of when aliens can threaten our cultural heritage or being part of it
Toxicity of five Cry proteins against the insect pest Acanthoscelides obtectus (Coleoptera: Chrisomelidae: Bruchinae).
2019
Abstract The beetle Acanthoscelides obtectus (Say) causes severe post-harvest losses in the common bean (Phaseolus vulgaris). Under laboratory conditions, the susceptibility of A. obtectus to five coleopteran-specific Cry toxic proteins from Bacillus thuringiensis (Cry1Ba, Cry1Ia, Cry3Aa, Cry7Ab, and Cry23/37) was evaluated. After 30 days exposure, Cry proteins demonstrated high activity against A. obtectus adults (100% mortality). Proteins showed statistical differences in toxicity parameters compared to the control treatment, but the parameters were similar among them, and indicated that the final toxic effects can be observed after the 24th day. The toxic effects on A. obtectus larvae we…
Invasive Alien Plants in Sub-Saharan Africa: A Review and Synthesis of Their Insecticidal Activities
2021
Despite the cornucopia of agricultural, economic and ecological ramifications of invasive alien plant species (IAPs) in sub-Saharan Africa, studies on their potential use as bio-insecticides have not received adequate attention compared to the burgeoning plethora of literature on their use in ethnomedicine. In the current study, we review the existing, but scattered literature on the insecticidal activity of different parts of some IAPs; specifically those invasive in sub-Saharan Africa but with published literature from Africa and elsewhere. From our literature survey, we found that 69 studies from four continents (Africa, Asia, North America and South America) reported the insecticidal ac…
Insecticidal spectrum and mode of action of the Bacillus thuringiensis Vip3Ca insecticidal protein.
2016
The Vip3Ca protein, discovered in a screening of Spanish collections of Bacillus thuringiensis, was known to be toxic to Chrysodeixis chalcites, Mamestra brassicae and Trichoplusia ni. In the present study, its activity has been tested with additional insect species and we found that Cydia pomonella is moderately susceptible to this protein. Vip3Ca (of approximately 90 kDa) was processed to an approximately 70 kDa protein when incubated with midgut juice in all tested species. The kinetics of proteolysis correlated with the susceptibility of the insect species to Vip3Ca. The activation was faster to slower in the following order: M. brassicae (susceptible), Spodoptera littoralis (moderately…
Susceptibility of Spodoptera frugiperda and S. exigua to Bacillus thuringiensis Vip3Aa insecticidal protein
2011
The Vip3Aa protein is an insecticidal protein secreted by Bacillus thuringiensis during the vegetative stage of growth. The activity of this protein has been tested after different steps/protocols of purification using Spodoptera frugiperda as a control insect. The results showed that the Vip3Aa protoxin was stable and retained full toxicity after being subjected to common biochemical steps used in protein purification. Bioassays with the protoxin in S. frugiperda and S. exigua showed pronounced differences in LC(50) values when mortality was measured at 7 vs. 10d. At 7d most live larvae were arrested in their development. LC(50) values of "functional mortality" (dead larvae plus larvae rem…
Chemical Ecology of Insect Parasitoids: Towards a New Era
2013
Over the course of evolutionary time, insect parasitoids have developed diverse strategies for using chemical compounds to communicate with various protagonists within their environment (i.e. conspecifi cs, their hosts, and the plants on which their hosts are living). Unravelling the evolutionary meaning of such chemical communication networks not only provides new insights into the ecology of these insects but also contributes to improving the use of parasitoids for the control of insect pests in biological control programmes. A book covering our current knowledge of the chemical ecology of insect parasitoids is therefore particularly timely and will appeal to a large number of potential r…
Intraguild interactions between two egg parasitoids of a true bug in semi-field and field conditions.
2014
International audience; Research on interspecific competitive interactions among insect parasitoids has often been characterized by laboratory studies in which host insects are exposed to female parasitoids of different species in various sequences and combinations. In the last years, an increasing number of studies have investigated interspecific interactions under field and semi-field conditions although just a few number of works focused on egg parasitoids. In this work, we undertook a two-year study to investigate interspecific interactions between Trissolcus basalis (Wollaston) (Hymenoptera: Platygastridae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), two egg para…
Complex responses of global insect pests to climate warming
2020
Although it is well known that insects are sensitive to temperature, how they will be affected by ongoing global warming remains uncertain because these responses are multifaceted and ecologically complex. We reviewed the effects of climate warming on 31 globally important phytophagous (plant‐eating) insect pests to determine whether general trends in their responses to warming were detectable. We included four response categories (range expansion, life history, population dynamics, and trophic interactions) in this assessment. For the majority of these species, we identified at least one response to warming that affects the severity of the threat they pose as pests. Among these insect spec…
Effect of Cry Toxins on Xylotrechus arvicola (Coleoptera: Cerambycidae) Larvae
2022
Simple Summary Xylotrechus arvicola is a destructive pest in vineyards (Vitis vinifera) in the main wine-producing areas of the Iberian Peninsula. X. arvicola larvae bore into the grapevine wood-making galleries, thus damaging the plant both directly and indirectly. The susceptibility of X. arvicola larvae to five coleopteran toxic Cry proteins was evaluated under laboratory conditions in order to deepen the knowledge of the effect of these proteins on this insect throughout its biological development. The Cry proteins tested could be applied to control X. arvicola larvae since they were able to kill them and cause serious alterations in the larvae during the remaining months of development…