Efficacy of kaolin Foliar Application Aga inst Tomato Whitefly; Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae)

Nowadays, nonchemical pest control replacements are being required. This research aims to study the efficacy of Kaolin (clay mineral) foliar application on the development of whitefly Bemisia tabaci (Genndius) (Hemiptera: Aleyrodidae) population on tomato plants. Two field experiments were performed at Qalubiya governorate, Egypt through three successive seasons (2014, 2015 and 2016). The first experiment was carried out in 2014 to evaluate the reduction effect of two Kaolin concentrations (2.5% and 5% W/V)) compared with two recommended pesticides; Acetamiprid (Mospilan SP 20) and Orange oil (Prev-AM) on B. tabaci. The results revealed that the initial effect of Acetamiprid and kaolin 5% were superior in activity with 91.6% and 90.1% reduction in whitefly adults population. Similar efficacy for Acetamiprid and 5% Kaolin were found on nymphs (89% and 85.7% respectively). The second experiment was conducted to study the impact of repeated foliar applications of Kaolin; 2.5% and 5% (W/V), compared with the two insecticides; Acetamiprid (Mospilan SP 20) and Orange oil (Prev-AM), on population fluctuation of whitefly stages (adults and nymphs) during summer plantation of 2015 and 2016 seasons. For both studied seasons no significant differences were found between the main numbers of whitefly adults recorded on plants treated with either Acetamiprid (3.5 and 4.1 adult/leaf) or Kaolin 5% (4.6 and 5.0 adult/leaf).  Moreover, no significant differences were found between orange oil treatment (9.4 and 10.0 adult / leaf) and Kaolin 2.5% treatment (8.9 and 9.5 adult/leaf). Similar trends were obtained with whitefly nymphs where, Kaolin 5% and Acetamiprid had the same reduction effect. In conclusion, the use of Kaolin foliar application can be considered in a program of agricultural management since it can control a high percentage of whitefly; Kaolin particles act as a barrier repelling infestations.