INSECTICIDAL AND ACARICIDAL ACTIVITY OF CARVACROL AND BETA-THUJAPLICINE DERIVED FROM THUJOPSIS-DOLABRATA VAR. HONDAI SAWDUST

Insecticidal and acaricidal components from sawdust of Thujopsis dolab rata var. hondai against eight species of anthropod pests (Reticuliter mes speratus, Lasioderma serricorne, Callosobruchus chinensis, Sitophi lus oryzae, Plutella xylostella, Myzus persicae, Blatella germanica, a nd Tetranychus urticae) were isolated by chromatographic techniques an d characterized by spectroscopic analyses as the terpenoids carvacrol and beta-thujaplicine. In tests using the filter paper diffusion metho d, carvacrol had broad insecticidal and acaricidal activity against ag ricultural, stored-product, and medical arthropod pests. However, beta -thujaplicine showed only weak termiticidal activity. Insecticidal act ivity of carvacrol was attributable to fumigant action. As a naturally occurring insecticide, carvacrol could be useful as a new preventive agent against damage caused by these arthropod pests.