The present work aims to determine the yield and chemical composition of the essential oil of
Piper callosum and to evaluate its insecticidal activity against Z subfasiatus. The collection of
the botanical material was carried out in March at the Institute of Exact Sciences and
Technology (ICET / UFAM), in the city of Itacoatiara (AM). By hydrodistillation using
Clevenger apparatus two oils with different densities were obtained in relation to water. The
less dense oil (OE1P4) had yield of 0.18%, and the denser oil (OE2P4) had 16% yield. The
oil samples were submitted to GC-MS analysis on SHIMADZU equipment coupled to a
SHIMADZU QP2010 mass spectrometer, and then the identification of the substances was
performed. The major compounds found were safrol (47.16%), β - pinene (10.72%), and
methyl eugenol (7.41%) in the less dense essential oil. Andsafrole (79.26%) and β - pinene
(5.73%) in the most dense essential oil. For the bioassay the concentrations 0; 0.002; 0.004;
0.006; 0.008 and 0.01μL / L of air and were evaluated at 24, 48 and 72 hours of exposure on
5 couples of Z. subfasciatus. Mortality was observed in 100% of the insects during the 48 h
exposure period at the concentration of 0.01 μL / L of air (LD 50 of 0.41 μL / L of air).
Considering the variety of substances found in the oil of P. callosum and its toxic action
against the insect Z. subfasciatus, it can be considered a great promise for future studies
aimed at finding sustainable insecticides that can combat pests of stored grains.
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