Synthesis of Zingiber officinale essential oil-loaded nanofiber and its evaluation on the potato tuber moth, Phthorimaea operculella (Lepidoptera: Gelechiidae)

The potato tuber moth (PTM), Phthorimaea operculella (Zeller), is a major pest of potato, both in the field and storehouses. In this study, we have evaluated the lethal effects and persistence of Zingiber officinale (Roscoe) pure (PEO) and nano-formulated essential oil (NFO) on different developmental stages (egg, male and female adults) of PTM. Essential oil was extracted by hydro-distillation using a Clevenger-type apparatus. The essential oil was analyzed by gas chromatography/mass spectrometry (GC/MS). Nanofibers were produced by electrospinning technique. The morphology of nanofibers was investigated by SEM. Fourier transform infrared (FTIR) was used to identify the characteristic functional groups in the PEO, nanofiber and PEO/NFO scaffold. Bioassays were performed in 250 ml glass jars. The essential oil consisted of α-Zingiberene as the most abundant component (14.21%), followed by Ar-curcumene (12.58%), β-sesquiphellandrene (12.48%) and cis-α-bisabolene (10.29%). The results of FTIR spectra showed the establishment of the functional groups of PEO on the structure of the nanofiber. The images of SEM also demonstrated the establishment of PEO in the structure of the nanofiber. LC50 values of PEO and NFO were estimated 75.44 and 30.24µl/l air for eggs, 19.08 and 10.28µl/l air for female adults, and 17.76 and 9.56µl/l air for male adults, respectively. Persistence data showed that nano-formulated essential oil (49 days) in comparison with pure essential oil (15 day) had longer persistence. The results demonstrated that Z. officinale PEO and its nano-formulation could play an important role as natural pesticides for the management of PTM.