Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin.The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.

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In recent years, nanotechnology has become one of the most promising new approaches for pest control. In our screening program, laboratory trials were conducted to determine the effectiveness of five sources of silver nanoparticles (Ag NPs) and sulfur nanoparticles (S NPs) on larval, pupal, and adults of the fruit flyDrosophila melanogaster. Nanoparticles of silver and sulfur were synthesized through reducing, stabilizing, and capping plant leaf extracts method and different concentrations (10, 50, 100, 200 ppm) were tested onD. melanogaster. Results showed that silver nanoparticles (Ag NPs) were highly effective on larvae, pupae, and adults’ mortality and egg deterrence. On the contrary, none of the tested nanoparticles has a significant effect on pupae longevity. The results also showed that silver nanoparticles can be used as a valuable tool in pest management programs ofD. melanogaster.

A method for mass rearing the parasitoid Neochrysocharis formosa (Westwood) was developed, using the leafminer Liriomyza huidobrensis (Blanchard) as insect host, and the Phaseolus vulgaris L. bean as host plant. About 1,500 parasitoids per tray of 84 plants emerged from about 2,000 leafminer larvae; 70% of these were females. The most suitable release density of host was two pairs of leafminer adults per bean plant, and that of parasitoid was three pairs per 24 leafminer larvae. Adult parasitoids were harvested based on positive photo-tactic response with 94.5% efficiency. Plants were improved by trimming their tips to increase the leaf area. The trimming process increased the number of leafminer larvae by about 32%. Furthermore, nitrogen fertilization of plants overcame the size reduction of the insects due to continuous rearing. Rearing of leafminer under light-dark (16:8 h) cycle decreased the development period of larvae and pupae. In addition, it restricted the time and duration of larval emergence and adult eclosion. Storage of parasitoid males and females at 7 and 10°C ± 0.5, respectively, proved to be optimal. The fertility of the massproduced parasitoids after 1 year of rearing reduced by about 23%, and the sex ratio shifted toward males. In conclusion, successful mass production of N. formosa was achieved through designing suitable rearing cage and an efficient harvesting device, improving the host plant, and determining the age and the conditions for cold storage of the parasitoid and its host. Next, we checked the characteristics of the massproduced wasps to ensure the efficacy when used in the field.

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