Plant essential oils emit a diverse bunch of volatiles which show potential to control numerous insect pests. Odor appreciation is highly precise, and the odors which affect an insect may not necessarily affect one another. This work assessed the influence of two aromatic essential oils Citronella grass Cymbopogon winterianus Jowitt and Tea tree Melaleuca alternifolia (Maiden & Betche) Cheel, challenging with Tio2 nanoparticles against the American serpentine leafminer Liriomyza trifolii L. For this purpose, free choice and no-choice in addition to olfactory response bioassays were done. Results showed that feeding punctures/cm2 and mining larvae/plant were significantly decreased in the treated plants. Significant more eclosed pupae and emerged adults were observed on untreated plants. The embryonic development time was not influenced by the treatments, however plants treated with Tio2 was more erect and abrasive which resulted in significant elongation in larval stage period. Plants treated with Tio2 altered the sex ratio, where 49.69 % of emerged adults were males. No statistical differences were detected in pupae weight among treatments. Oflactory bioassay showed that significant fewer females were attracted toward the three treated materials than non-treated control. Data suggest the successful use of natural compounds in leafminers management programs.
Key words: Pest management, olfactory, repellents, sex ratio, no-choice bioassay, aromatic herbs.