Biorational control of arthropod pests with emphasis on the use of the chitin synthesis inhibitor novaluron

Efforts have been made during the past three decades to develop insecticides with selective properties that act specifically on biochemical sites present in a particular insect group, but whose properties differ from those present in mammals. This approach has led to the discovery of compounds that affect the hormonal regulation of molting and developmental processes in insects such as ecdysone agonists, juvenile hormone (JH) mimics and chitin synthesis inhibitors. The search for potent acylureas has led to the development of novaluron (Rimon) developed by Makhteshim Chemical Works. The LC-50 value of novaluron on 3rd-instar Spodoptera littoralis fed on treated leaves is approximately 0.1 mg a.i./liter. This value resembles that of chlorfluazuron and is tenfold lower than that of teflubenzuron. Novaluron affects nymphs of Bemisia tabaci more than chlorfluazuron and teflubenzuron. Artificial rain, at a rate of 40 mm/h applied 5 and 24 h after treatment in a cotton field had no appreciable effect on the potency of novaluron on both S. littoralis larvae and B. tabaci nymphs. Hence, novaluron can be used in tropical areas and during rainy seasons. In general, benzoylphenyl ureas had no direct effect on parasitoids and phytoseiids and are considered mildly affect other natural enemies. Novaluron has no cross-resistance with conventional insecticides, the JH mimics pyriproxyfen and neonicotinoids. As such, it is considered an important compound in pest management programs.