In this study, the volatile compounds found in lemon trees infested and uninfested with Planococcus citri (Risso) (Hemiptera: Pseudococcidae) were investigated. In addition, the interest of the predator Cryptolaemus montrouzieri (Coleoptera: Coccinellidae) and the parasitoid Leptomastix dactylopii (Hymenoptera: Encyrtidae) in lemon trees infested and uninfested with P. citri and some volatile compounds was investigated. According to the results obtained, most of the volatile compounds obtained from mealybug-infested lemon trees showed changes compared to healthy lemon trees. Since volatile compounds play an important role in attracting pests and natural enemies, linalyl acetate was selected as the compound showing the highest amount of changes, and its attractiveness to predators and parasitoids was tested first in the laboratory using a Y olfactometer and then in a lemon orchard in combination with a yellow sticky trap. In the olfactometer tests, linalyl acetate was found to be attractive to predators and parasitoids. In field studies, the number of predators and parasitoids increased in traps containing linalyl acetate compared to traps containing only paraffin oil. Our results suggest that linalyl acetate may play a role in attracting both predators and parasitoids and can be combined with these natural enemies in biological control studies.
