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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Chemical composition and in vitro antimicrobial, insecticidal and antioxidant activities of the essential oils of Mentha pulegium L. and Mentha rotundifolia (L.) Huds growing in Algeria
Fatiha Brahmi,Adjaoud Abdenour,Marongiu Bruno,Porcedda Silvia,Piras Alessandra,Falconieri Danilo,Yalaoui-Guellal Drifa,Elsebai Mahmoud Fahmi,Madani Khodir,Chibane Mohamed +9 more
TL;DR: The essential oils of Mentha rotundifolia (L.) Huds (MRE) which are growing in Algeria were prepared by hydrodistillation and their chemical compositions investigated by GC/MS as mentioned in this paper.
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Molluscicidal Saponins from Sapindus mukorossi, Inhibitory Agents of Golden Apple Snails, Pomacea canaliculata
TL;DR: Bioassay-directed fractionation of S. mukorossi resulted in the isolation of one new hederagenin-based acetylated saponin, causing 70-100% mortality at 10 ppm against the golden apple snail.
Journal ArticleDOI
Effect of Insecticides on the Diamondback Moth (Lepidoptera: Plutellidae) and Its Parasitoid Diadegma insulare (Hymenoptera: Ichneumonidae)
Travis A. Hill,Rick E. Foster +1 more
TL;DR: Larval mortalities at field rates were significantly higher with carbaryl, permethrin, spinosad, and tebufenozide when compared with Bacillus thuringiensis, or imidacloprid in the larval-dip bioassay 72 h after treatment.
Journal ArticleDOI
Efficacy of entomopathogenic nematodes against the tomato leafminer Tuta absoluta in laboratory and greenhouse conditions
TL;DR: The results demonstrate the suitability of entomopathogenic nematodes for controlling T. absoluta and reduce insect infection of tomato plants by 87–95%.
Journal ArticleDOI
Insecticidal properties of Pimpinella anisum essential oils against the Culex quinquefasciatus and the non-target organism Daphnia magna
TL;DR: The essential oil and trans-Anethole were toxic for Daphnia magna and significantly reduced its fertility at high concentrations (35–50 μL mL− 1) and long exposure (48 h) and no negative effect on DAPHnia mortality or fertility was found at shorter exposure times and/or lower concentrations.