The ATTRACTIVE PREFERENCE OF Chrysoperla externa (NEUROPTERA: CHRYSOPIDAE) FOR OLFACTORY STIMULUS

Abstract

Biological control naturally regulates pests in agriculture. The study evaluated the attraction of coffee leaves to adult females and larvae of Chrysoperla externa, an important predator in the biological control of the coffee leaf miner in coffee farming. A Y-shaped olfactometer was used in the Insect Behavior Laboratory – LaCI, UNIPAM. In the clean air vs clean air test, two insects chose one side of the Y. Between clean air vs healthy leaves, 50% chose healthy leaves and 50% chose clean air. In the clean air vs leaves infested with the coffee leaf miner, 56.25% opted for the infested leaves, while 43.75% chose clean air. Comparing infested leaves vs healthy leaves from different plants, 57.1% preferred the leaves with the coffee leaf miner and 42.8% preferred the healthy leaves. When the infested and healthy leaves were from the same plant, 41.6% chose infested leaves and 58.4% chose healthy leaves. For the larvae, in the clean air vs clean air treatment, there was no choice. Between clean air vs healthy leaves, 37.5% preferred healthy leaves and 62.5% chose clean air. In the clean air vs infested leaves test, 75% chose the infested leaves, and 25% chose clean air. Comparing healthy leaves vs infested leaves from different plants, 66.6% opted for the leaves with the pest, while 33.3% chose the healthy leaves. When the leaves were from the same plant, 75% chose the infested leaves and 25% chose the healthy ones. Therefore, it is concluded that the larvae of C. externa responded more efficiently to the presence of the coffee leaf miner in coffee leaves during the study.