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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Goniothalamin – a potent mosquito larvicide from Bryonopsis laciniosa L.
TL;DR: Goniothalamin isolated from the indigenous plant, Bryonopsis laciniosa L., was highly effective against the larvae of the mosquito, Culex quinquefasciatus Say, as a mosquitocide.
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Field Evaluation of Repellent Formulations Against Daytime and Nighttime Biting Mosquitoes in a Tropical Rainforest in Northern Australia
TL;DR: Field trials to compare repellent formulations containing either picaridin or deet against rainforest mosquitoes in northern Queensland, Australia, found that 19.2% picarodin provided similar or better protection than deet formulations.
Journal ArticleDOI
Distribution of the entomopathogenic nematodes from La Rioja (Northern Spain).
Raquel Campos-Herrera,Miguel Escuer,S. Labrador,Lee Robertson,Laura Barrios,Carmen Gutiérrez +5 more
TL;DR: Entomopathogenic nematodes distribution in natural areas and crop field edges in La Rioja (Northern Spain) has been studied taking into account environmental and physical-chemical soil factors and the ecological trends and biological results are discussed.
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Fipronil seed treatments for the control of chironomid larvae /Diptera: Chironomidae in aerially-sown rice crops
TL;DR: The results indicate that fipronil applied to seed at 12.5 g active ha−1 is a more efficacious seed treatment than malathion at 300 g activeHa−1 and provides protection against chironomids for 9–14 DAS.
Journal ArticleDOI
Interference of ants (Hymenoptera: Formicidae) with biological control of the vine mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae).
Nyembezi Mgocheki,Pia Addison +1 more
TL;DR: In South Africa, three ant species, Anoplolepis steingroeveri , Crematogaster peringueyi and Linepithema humile form a trophobiotic relationship with the vine mealybug in vineyards and promote the latter’s infestations to unacceptable levels.