Azadirachtin and neem aqueous extracts applied to melon root system to whitefly control.

Abstract

As an alternative to agrochemicals, we studied the systemic effect of azadirachtin and neem leaves (Azadirachta indica) and seed extracts against the melon whitefly, Bemisia tabaci biotype B in greenhouse environment at “Universidade Federal do Ceará”. The treatments were applied on the soil near the plant. At 24 ppm, the azadirachtin reduced meaningly whitefly nymphs. There was a progressive increase of efficiency in the other dosages. On the other hand, seed extract was only effective at 16 g.100 mL when we noticed the average of 4.66 nymphs compared to 18.15 nymphs found on untreated plants. This denoted a reduction of 74.33%. Leaf extracts showed minimal effect with an efficiency of only 32.83%. The reduction of the nymphs caused by the standard imidacloprid insecticide was superior to the extracts.