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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The insecticidal activity of Tanacetum parthenium (L.) Schultz Bip. extracts obtained by supercritical fluid extraction and hydrodistillation
TL;DR: In this article, CO2 extracts and essential oil obtained by hydrodistillation from feverfew aerial parts were applied to Spodoptera littoralis (Boisduval) larvae to examine their effects on mortality, antifeedancy and growth inhibition, and their composition of volatile substances was determined using GC.
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Evaluation of the toxicity of 17 essential oils against Choristoneura rosaceana (Lepidoptera: Tortricidae) and Trichoplusia ni (Lepidoptera: Noctuidae)
TL;DR: In this paper, a selection of 17 essential oils was screened against both lepidopteran pests, and the influence of azinphos-methyl resistance on essential oil toxicity to C. rosaceana was studied.
Journal ArticleDOI
Insecticidal activity of camphene, zerumbone and α-humulene from Cheilocostus speciosus rhizome essential oil against the Old-World bollworm, Helicoverpa armigera.
Giovanni Benelli,Giovanni Benelli,Marimuthu Govindarajan,Marimuthu Govindarajan,Mohan Rajeswary,Baskaralingam Vaseeharan,Sami AlYahya,Naiyf S. Alharbi,Shine Kadaikunnan,Jamal M. Khaled,Filippo Maggi +10 more
TL;DR: This study represents the first report on the toxicity of C. speciosus essential oil against insect pests of agricultural and medical veterinary importance, highlighting that camphene, zerumbone and α-humulene have a promising potential as eco-friendly botanical insecticides.
Journal ArticleDOI
Efficacy of two tropical plant extracts for the control of mosquitoes
E. Pushpalatha,J. Muthukrishnan +1 more
TL;DR: Experiments under laboratory and semi‐field conditions showed that the activity of the extracts persisted for up to 10 days, and inhibited 50% of the treated larvae from emerging as adults.
Journal ArticleDOI
Green synthesis of silver nanoparticles using latex extract of Euphorbia tirucalli: A novel approach for the management of root knot nematode, Meloidogyne incognita
TL;DR: It is concluded that Et-AgNPs are helpful for the management of M. incognita and will be an effective replacement for synthetic nematicides.