Tropical Andes is a biodiversity hot spot rich in aromatic plant species, whose potential as a source
of active compounds for insect pests’ control is still largely underexploited. Here, the Essential Oils
(EOs) extracted from two Ecuadorian plants, the shrub Aloysia citriodora (Verbenaceae) and the
tree Bursera graveolens (Burseraceae), were chemically analysed and tested for their bioactivity
against the blue blowfly Calliphora vomitoria (Linnaeus, 1758) (Diptera: Calliphoridae). This fly is a
vector of pathogenic microorganisms, dangerous in factories and stores where fresh meat is
processed, stored, and sold. The main components of the A. citriodora EO are geranial and
limonene, while in the B. graveolens EO they are limonene and α-terpineol. The effects of the two
EOs were evaluated against C. vomitoria by a behavioural assay in a two-choice olfactometer
(concentrations range 0.07-2.8 μL L-1 air). Besides, the insecticidal properties of the two EOs were
tested by fumigation (EOs concentrations from 6.06 to 36.36 μL L-1 air), by contact with topical
applications using a Burkard micro dispenser (EOs dose from 0.10 to 0.60 μl EO/fly), and by
ingestion of a mucilage containing EOs (from 15 to 75 μl EO mL-1 mucilage), sucrose, and agarose.
Furthermore, the ovicidal activity was assessed (concentrations from 0.006 to 0.075 μL EO cm-2 of
filter paper). The results of the behavioural assay showed a stronger repellent effect exerted by
the A. citriodora EO, while all the toxicity tests revealed dose-dependent mortality of the blowflies
and eggs
