Search results for "insektisidit"
showing 5 items of 5 documents
Prolonged diapause has sex-specific fertility and fitness costs
2019
AbstractDiapause in seasonal environments allows insects to survive adverse seasons. However, individuals can sometimes enter a prolonged diapause for more than a year, and also skip favourable seasons, which can bring additional costs through e.g. loss of metabolic resources. At the same time, prolonged diapause can be beneficial if it allows individuals to have a risk-spreading strategy to skip potentially suboptimal breeding seasons. We studied if prolonged diapause (2-year diapause) negatively affects the fertility and fitness of female and male Colorado potato beetles (Leptinotarsa decemlineata) compared to control (1-year diapause) beetles. We also tested the parental effects on the s…
Transgenerational effects of insecticides - implications for rapid pest evolution in agroecosystems
2018
Although pesticides are a major selective force in driving the evolution of insect pests, the evolutionary processes that give rise to insecticide resistance remain poorly understood. Insecticide resistance has been widely observed to increase with frequent and intense insecticide exposure, but can be lost following the relaxation of insecticide use. One possible but rarely explored explanation is that insecticide resistance may be associated with epigenetic modifications, which influence the patterning of gene expression without changing underlying DNA sequence. Epigenetic modifications such as DNA methylation, histone modifications, and small RNAs have been observed to be heritable in art…
Sequence variation and regulatory variation in acetylcholinesterase genes contribute to insecticide resistance in different populations of Leptinotar…
2021
Abstract Although insect herbivores are known to evolve resistance to insecticides through multiple genetic mechanisms, resistance in individual species has been assumed to follow the same mechanism. While both mutations in the target site insensitivity and increased amplification are known to contribute to insecticide resistance, little is known about the degree to which geographic populations of the same species differ at the target site in a response to insecticides. We tested structural (e.g., mutation profiles) and regulatory (e.g., the gene expression of Ldace1 and Ldace2, AChE activity) differences between two populations (Vermont, USA and Belchow, Poland) of the Colorado potato beet…
Sublethal Pyrethroid Insecticide Exposure Carries Positive Fitness Effects Over Generations in a Pest Insect
2019
AbstractStress tolerance and adaptation to stress are known to facilitate species invasions. Many invasive species are also pests and insecticides are used to control them, which could shape their overall tolerance to stress. It is well-known that heavy insecticide usage leads to selection of resistant genotypes but less is known about potential effects of mild sublethal insecticide usage. We studied whether stressful, sublethal pyrethroid insecticide exposure has within-generational and/or maternal transgenerational effects on fitness-related traits in the Colorado potato beetle (Leptinotarsa decemlineata) and whether maternal insecticide exposure affects insecticide tolerance of offspring…
Adaptation to stressful environments : invasion success of the Colorado potato beetle (Leptinotarsa decemlineata)
2018
Biological invasions, specifically human-induced dispersals, are one of the major threats to our biodiversity and are predicted to increase. Invasive pests provide an opportunity to study whether adaptation to human-induced environments could promote invasions to other human-induced environments. One major anthropogenic selection pressure is created by pesticides, and pests can be exposed to various pesticides in their native, as well as introduced, ranges. I investigated whether exposure to anthropogenic selection (i.e. insecticides and herbicides) and exposure to multiple anthropogenic stressors selects for higher stress tolerance. I also tested whether parental prolonged diapause or inse…