Enhancing the foraging efficiency of the predatory mite Amblyseius largoensis through conditioning with herbivore-induced plant volatiles
2026 - Volume: 66 Issue: Suppl pages: 157
https://doi.org/10.24349/xpwi-pfhp
ICA 2026 - XVII International Congress of Acarology, 20-24 July 2026, Montpellier
Keywords
Amblyseius largoensis
Herbivore-induced plant volatiles
Olfactory conditioning
Volatile organic compounds
Biological control
Abstract
Biological control using predatory mites plays a crucial role in sustainable pest management in many agricultural systems. However, improving the efficiency of natural enemies in locating prey remains a major challenge. Herbivore-induced plant volatiles (HIPVs) released by plants under herbivore attack can serve as important cues guiding predators toward infested plants. The present study evaluated whether exposure of predatory mites to specific HIPVs could enhance their orientation behavior, predation efficiency, and population performance. The predatory mite Amblyseius largoensis was conditioned with volatile cues obtained from herbivore-infested citrus leaves as well as selected synthetic volatile organic compounds (VOCs). Behavioral responses were assessed using Y-tube olfactometer bioassays to determine predator preference between infested and non-infested plant odors. Each olfactometer treatment was replicated 30 times. In addition, laboratory experiments examining the effects of conditioning on prey searching time, prey consumption, survival, reproduction, and population development were conducted with five replicates per treatment. Gas chromatography–mass spectrometry (GC– MS) analysis was used to characterize the volatile profile emitted by infested citrus plants and to identify major compounds associated with predator attraction. Conditioned mites showed a significantly stronger attraction toward odors from herbivore-infested plants compared with unconditioned individuals, indicating an enhanced ability to recognize prey-associated cues. Training with plant-derived volatiles resulted in improved foraging performance, including shorter prey detection time, increased locomotory activity during prey searching, and higher prey consumption rates. Furthermore, conditioned predators exhibited improved biological parameters such as survival, fecundity, and overall population growth. Chemical analysis of HIPVs revealed several sesquiterpenes, including a-farnesene, caryophyllene, and humulene, as prominent components potentially involved in predator attraction. Experiments with selected VOCs further demonstrated compound-specific responses, suggesting that exposure to key volatiles can reinforce predator orientation toward infested plants.
Comments
Please read and follow the
instructions
to post any comment or correction.