ABSTRACT
The neem seed and other parts of the tree contain insecticidal tetranortriterpenoids such as azadirachtin, meliantriol, and salannin, which act in insects as antifeedants, as insect growth and development regulators, or even as toxicants. Detailed data from the Insects Affecting Man and Animal Research Laboratory at Gainesville, Fla. showed that azadirachtin in mosquito cloth repeliency tests was less active than Deet and DMP. Bidmon et al, investigated biological effects of azadirachtin in blow fly larvae. Gill offered neem kernel water extract, alcohol extract, or azadirachtin at the extremely low concentration in a 1 M sucrose solution to adult house flies for 3 d. A 3% emulsion of neem oil sprayed over the back of the animal deterred blow flies from ovipositing for 8 d, which was longer than with some other oils but less effective than olive, cotton seed, castor and soybean oil, and oleic acid.
