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
Resistance of Bemisia tabaci (Homoptera: Aleyrodidae) to insecticides in southern Spain with special reference to neonicotinoids.
Alfred Elbert,Ralf Nauen +1 more
TL;DR: Systemic bioassays using Spanish field populations of B tabaci collected in 1994, 1996 and 1998 indicated an increase, albeit a slow one, in resistance to imidacloprid over this period, and Comparative studies of other neonicotinoids using the same bioassay revealed a high degree of cross-resistance to acetamiprid and thiamethoxam.
Journal ArticleDOI
Proteinase-mediated insect resistance to bacillus thuringiensis toxins
TL;DR: Two Bacillus thuringiensis(Bt)-resistant strains of the Indianmeal moth lack a major gut proteinase that activates Bt protoxins, providing evidence that insect adaptation to these toxins occurs through multiple physiological mechanisms, which complicate efforts to prevent or manage resistance to Bt toxins in insect control programs.
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Insecticide resistance in field populations of Asian citrus psyllid in Florida
TL;DR: It is suggested that varying levels of insecticide susceptibility exist in ACP populations across the citrus-growing areas of Florida and insecticide resistance may become an emerging problem for ACP control if effective resistance management is not practiced.
Journal ArticleDOI
Evaluation of green synthesized silver nanoparticles against parasites
Sampath Marimuthu,Abdul Abdul Rahuman,Govindasamy Rajakumar,Thirunavukkarasu Santhoshkumar,Arivarasan Vishnu Kirthi,Chidambaram Jayaseelan,Asokan Bagavan,Abdul Abduz Zahir,Gandhi Elango,Chinnaperumal Kamaraj +9 more
TL;DR: The maximum efficacy was observed in synthesized AgNPs against the larvae of A. subpictus, C. quinquefasciatus, and R. microplus and this is the first report on antiparasitic activity of the plant extract and synthesised AgNPS.
Journal ArticleDOI
Learning performances of honeybees (Apis mellifera L) are differentially affected by imidacloprid according to the season.
TL;DR: The LOEC of imidacloprid was lower in summer bees than in winter bees, which points to a greater sensitivity of honeybees behaviour in summer Bees, compared to winter bees.