Journal ArticleDOI
A method of computing the effectiveness of an insecticide
TLDR
In order to make experimental studies comparable and statistically meaningful, the article recommends the following formula: per cent control = 100(X - Y)/X, which eliminates errors due to deaths in the control sample which were not due to the insecticide.Abstract:
There are several statistical methods used in biology (entomology) for computing the effectiveness of an insecticide, based on relating the number of dead insects in the treated plat to the number of live ones in the untreated plat. In order to make experimental studies comparable and statistically meaningful, the article recommends the following formula: per cent control = 100(X - Y)/X, where X = % living in the untreated check sample and Y = % living in the treated sample. Calculation using this method eliminates errors due to deaths in the control sample which were not due to the insecticide. An example based on treatments of San Jose scale includes computation of probable errors for X and Y, and the significance of the difference between the two counts. Common biometric convention holds that when the difference between the results of two experiments is greater than three times its probable error, the results are significant and due to the treatment applied.read more
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Journal ArticleDOI
Virulence of the entomopathogenic nematodes Heterorhabditis bacteriophora, Heterorhabditis zealandica, and Steinernema scarabaei against five white grub species (Coleoptera: Scarabaeidae) of economic importance in turfgrass in North America
TL;DR: The virulence of the nematode species relative to each other differed greatly among white grub species, with H. bacteriophora and H. zealandica having similar modest virulence to P. japonica, A. orientalis, C. borealis, and M. castanea, but against R. majalis, H. Zealandica showed low virulence with a clear concentration response whereas H. phytochemical caused only erratic and very low mortality.
Journal ArticleDOI
Repellency of controlled-release treated cotton fabrics based on cypermethrin and prallethrin
TL;DR: MCT-β-CD-finished cotton fabrics loaded with insecticides are effective in reducing malaria morbidity and mortality due to effective personal protection against mosquitoes and bioassays show that the treated fabrics have fast action against mosquitoes at the range of concentrations studied.
Book ChapterDOI
Saponins from Medicago SPP.: Chemical Characterization and Biological Activity Against Insects
Aldo Tava,Miriam Odoardi +1 more
TL;DR: The occurrence and distribution of secondary metabolites in plants, from an ecological viewpoint, can be associated with a defensive strategy of plants against herbivores and complex antibiotic substances such as alkaloids and terpenes provide inducible or constitutive defense both in woody and in herbaceous plants.
Journal ArticleDOI
Underpinning Sustainable Vector Control through Informed Insecticide Resistance Management
Edward K. Thomsen,Clare Strode,Kay Hemmings,Angela Hughes,Emmanuel Chanda,Mulenga Musapa,Mulakwa Kamuliwo,Faustina N. Phiri,Lucy Muzia,Javan Chanda,Alister Kandyata,Brian Chirwa,Kathleen Poer,Janet Hemingway,Charles S. Wondji,Hilary Ranson,Michael Coleman +16 more
TL;DR: The methods employed here can serve as a template to all malaria-endemic countries striving to create a sustainable insecticide resistance management plan.
Journal ArticleDOI
Effects of azadirachtin on Tetranychus urticae (Acari: Tetranychidae) and its compatibility with predatory mites (Acari: Phytoseiidae) on strawberry.
Daniel Bernardi,Marcos Botton,Uemerson Silva da Cunha,Oderlei Bernardi,Thibaut Malausa,Mauro Silveira Garcia,Dori Edson Nava +6 more
TL;DR: Azadirachtin provided effective control of T. urticae and is compatible with the predatory mites N. californicus and P. macropilis in strawberry crop, an excellent tool to be incorporated into integrated pest management for strawberry crop in Brazil.