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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Screening of twenty five plant extracts for larvicidal activity against Culex quinquefasciatus Say (Diptera: Culicidae)
TL;DR: The results indicate larvicidal activity against Cx.
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Nematicidal activities of Cannabis sativa L. and Zanthoxylum alatum Roxb. against Meloidogyne incognita
TL;DR: The results of the studies showed that the extracts of test plants possess high potentials for the control of root-knot nematodes and could be the possible replacement for synthetic nematicides.
Journal ArticleDOI
Boric acid toxicity to the German cockroach, Blattella germanica: Alterations in midgut structure, and acetylcholinesterase and glutathione S-transferase activity
TL;DR: It is concluded that ingested boric acid caused death of insects perhaps ultimately by starvation via alterations of the midgut and the compound seemed to present a neurotoxic action as evidenced by the symptoms of poisoning and the reduction in AchE activity.
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Entomopathogenic fungi of Eurygaster integriceps Puton (Hemiptera: Scutelleridae): collection and characterization for development
Bruce L. Parker,Margaret Skinner,Scott D. Costa,Svetlana Gouli,William Reid,Mustapha El Bouhssini +5 more
TL;DR: The results demonstrate the potential of entomopathogenic fungi for management of E. integriceps in overwintering sites and in wheat fields, particularly in the in-litter environment.
Journal ArticleDOI
Defensive chemistry of Senecio miser.
Matías Reina,Azucena González-Coloma,Carmen Gutiérrez,Raimundo Cabrera,M. L. Rodriguez,Víctor Fajardo,Luis Villarroel +6 more
TL;DR: Eremophilanolides 1 and 2 and alkaloids 4 and 5 were found to be strong insect antifeedants, further supporting a proposed defensive role for these classes of compounds.