مدیریت بید سیب زمینی Phthorimaea operculella (Zeller) با استفاده نانوالیاف های بارگزاری شده با اسانس پنج انگشت Vitex agnus-castus L.

Phthorimaea operculella (Zeller) is one of the most common insect pests of cultivated potato in tropical and subtropical regions. In this study, a potential strategy to improve the insecticidal activity of plant essential oils for the effective management of P. operculella was evaluated. The insecticidal and residual effects of nanofiber oil (NFO) and pure essential oil (PEO) of Vitex agnus-castus L. were assessed on PTM under laboratory conditions. The nanofibers were made by the electrospinning method using polyvinyl alcohol (PVA) polymer. The morphological characteristics of the nanofibers were evaluated by scanning electron microscopy and Fourier transform infrared spectroscopy. The chemical constituents of V.agnus-castus essential oil (EO) were detected by GC/MS. Fumigant toxicity of NFO and PEO were evaluated on different growth stages (egg, male and female adults) of P. operculella. SEM and FTIR analyses confirmed the presence of EO on the nanofiber structure. GC/MS analysis showed that 1,8-Cineole was the primary constituent (12.26%) of V.agnus-castus EO. LC50 values of V.agnus-castus EO and NFO were 47.92 and 23.72 μl/l air for eggs, 8.08 and 3.84 μl/l air for female adults, and 7.04 and 3.16 μl/l air for male adults, respectively. Fumigant bioassays revealed that NFO was more toxic than V.agnus-castus oil against at all stages of P. operculella. The residual effect of PEO and NFO was evaluated against the egg stage of the P. operculella. NFO lost insecticidal effectiveness 49 days after application, while the efficacy of PEO decreased 15 days after application. Our results suggest that NFO of V.agnus-castus can be used as an effective new tool for the management of P. operculella.