Insecticides from Neem

Derivatives of neem ( Azadirachta indica A. Juss) have traditionally been used by farmers in Asia and Africa to ward off insect pests of household, agricultural, and medical importance. Unlike ordinary insecticides based on single active ingredients, neem derivatives comprise a complex array of novel compounds which have diverse behavioral and physiological effects on insects. Repellency, feeding and oviposition deterrence, growth and reproduction inhibition, and other effects have been attributed to neem compounds - azadirachtin, salannin, meliantriol, etc. that occur mainly in the seed. However, the complexity of chemical structure of these compounds precludes their synthesis on a practical scale. Therefore, the use of simple formulations of neem derivatives such as leaf or kernel powder or extracts needs to be popularized. Their being safe to nontarget organisms, including humans, make them ideal insecticides. Several azadirachtinrich formulations have already been commercialized for use on nonfood and food crops.