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The cotton mealybug, Phenacoccus solenopsis Tinsley is an invasive polyphagous pest species causing severe economic damage to a wide range agricultural crops. Five different toxicants of different groups were evaluated for their effectiveness in reducing mealybug incidence on cotton under both laboratory and field conditions as well as their effectiveness against its associated predators (Chrysoperla carnea (Steph.), Hyperaspis vinciguerrae Capra) under field conditions. Chlorpyrifos and Imidacloprid were the most toxic insecticides after 24h and 72h of exposure compared with Pyriproxyfen, Buprofezin and Emamectin benzoate against third instar nymphs of P. solenopsis under laboratory conditions. Based on field experiments, Chlorpyrifos significantly superior in reducing the cotton mealybug population followed by Imidacloprid, Pyriproxyfen, Emamectin benzoate and finally Buprofezin with average reduction between 96.24 to 43.99%. IGRs toxicants (Buprofezin and Pyriproxyfen) found to safer to the predacious insects than other toxicant groups.

The effectiveness of technical products of Naled, Lambada, Fenthion (Lebaycid), Fenitrothion (Sumithion), Malathion and Dimethoate (mixed with methyl eugenol in the ratio of 1:4), in addition to commercial Malathion (57% EC mixed with methyl eugenol in two ratios of 1:2 and 2:3) were evaluated under field conditions as male annihilation technique (lure and kill) of Bactrocera zonata (Saunders) (Diptera: Tiphritidae). Plant fiber blocks saturated with mentioned mixtures were used at four governorates of Egypt (Damietta, Dakahlia, Ismailia and Fayoum) over 12 successive weeks. Efficiency (as lured and killed populations per block per day) of all tested mixtures degraded over time regardless the area. The obtained results revealed that Naled mixture was significantly superior to all other mixtures regard less area or inspection. Naled mixture blocks were relatively effective for up to 8 weeks while others efficiency did not exceed 4 weeks. Commercial Malathion (1:2), technical Malation, Dimethoate were the worth. It was recommended that Naled mixture can be used successfully in B. zonata male annihilation technique and renewed every two months. Lambada, Lebaycid, Sumithion, commercial Malathion (2:3) mixtures could be used with monthly renewal.