Olfactory responses of the leafminer Liriomyza cicerina (Diptera: Agromyzidae) to chickpea plant volatiles

Abstract

Introduction Chickpea ( Cicer arietinum L.) is an essential pulse crop in many countries, but its productivity is severely constrained by the leafminer Liriomyza cicerina (Rondani), a major chickpea pest in the Mediterranean region and North Africa. Host location by L. cicerina is strongly affected by plant-emitted volatile organic compounds (VOCs), which mediate insect host selection and oviposition. Understanding these chemical signals is essential for developing sustainable pest management strategies. Methods Y-tube olfactometer bioassays were conducted to evaluate the olfactory responses of adult leafminers to VOC blends from healthy and infested chickpea plants, to selected individual volatile compounds, and to VOCs released by chickpea varieties with distinct levels of resistance toward L. cicerina . Results and discussion Adult leafminers were significantly more attracted to VOCs emitted by healthy plants than to those released by infested plants. Among individual volatile compounds tested, trans-2-hexen-1-ol elicited the highest attraction (80%), whereas linalyl acetate induced the strongest repellence (73.3%). Moreover, VOC emissions varied among chickpea genotypes, influencing the host preference of L. cicerina . The susceptible variety Arifi (FLIP98-50 C) release more attractive VOC blends compared to the less susceptible genotypes tested. These findings highlight the ecological role of chickpea VOCs in mediating insect-plant interactions, with plant condition, genotype, and specific compounds shaping insect preference and host selection. Identifying attractive and repellent VOCs provides insights into the mechanisms underlying susceptibility and supports the development of sustainable pest management strategies, including monitoring lures, push–pull strategies, and selective breeding of less attractive chickpea varieties.