Does microemulsification improve the insecticidal activity of cypermethrin against the melon aphid, Aphis gossypii (Hemiptera: Aphididae)?

The melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae) is one of the important ornamental plant pests in urban regions. In this study, the microemulsion system was developed using cypermethrin insecticide as the active ingredient, xylene as the solvent, and surfactants including Tensiofix ۸۴۲۷ + SDS, and Tensiofix ۸۴۲۷ + SLS, and ۱-butanol (cosurfactant), as stabilizer. The optimal microemulsion formulation was determined using a pseudo-ternary phase diagram using the water titration method. The microemulsions mean droplet sizes were in the range ۱۱.۲–۲۲.۸ nm. The droplets of all three formulations were spherical and uniformly dispersed in water. The mortality percentage was ۶۶.۶۶, ۵۶.۶۶, and ۵۵.۰۰% ۲۴ h after aphids exposure to C۱-۲۵۰ (cypermethrin: Tensiofix ۸۴۲۷ + SDS + ۱-butanol: water, at the ratio of ۱۰:۲۰:۷۰), C۲-۲۵۰ (cypermethrin: Tensiofix ۸۴۲۷ + SLS + ۱-butanol: water, at the ratio of ۱۰:۲۰:۷۰), and C۳-۲۵۰ (cypermethrin: Tensiofix ۸۴۲۷ + SLS + ۱-butanol: water, at the ratio of ۱۵:۳۰:۵۵), which increased to ۹۲.۸۶, ۸۹.۲۹, and ۸۳.۹۴%, ۴۸ h after exposure, respectively. The results revealed that the microemulsion formulation containing cypermethrin ۲۵۰ g/L was more effective in controlling A. gossypii than cypermethrin technical material and ۱۵۰ g/L cypermethrin-based microemulsion.

کلیدواژه ها:

Cypermethrin ، green space ، microemulsion ، phase behavior ، surfactant ، zeta potential