Work

Multitarget Acaricidal Activity of Essential Oils from Alpinia zerumbet and Mesosphaerum suaveolens Against Tetranychus urticae

Year: 2025

Type: article

Abstract: The two-spotted spider mite, Tetranychus urticae, is a global pest with increasing resistance to conventional acaricides, prompting the search for sustainable alternatives. Essential oils (EOs) are promising botanical biocides due to ecological safety and multitarget action. We evaluated lethal and sublethal effects of EOs from Alpinia zerumbet and Mesosphaerum suaveolens against T. urticae. Oils were obtained by hydrodistillation and characterized by GC–MS (major constituents: A. zerumbet—1,8-cineole 14.05%, sabinene 12.6%; M. suaveolens—β-sabinene (predominant), spathulenol 12.28%, 1,8-cineole 11.01%). In adult bioassays, M. suaveolens was more toxic (LC50 = 4.24 µL mL−1), whereas A. zerumbet showed LC50 = 8.74 and LC90 = 46.24 µL mL−1. In ovicidal assays at LC90, egg viability declined to 2% with A. zerumbet versus 57% with M. suaveolens. Repellency at sublethal concentrations (LC20–LC30) was high for both oils (≥75%) and exceeded 90% for M. suaveolens. Both oils suppressed population growth (instantaneous rate ri reduced from 0.5848 in the control to 0.4746–0.5155 under treatments). PCA confirmed lethal concentration and repellency as the main discriminators among treatments. These data demonstrate the multitarget potential of A. zerumbet and M. suaveolens EOs as botanical acaricides for sustainable management of T. urticae.

Source: Insects

DOI: 10.3390/insects16111119