Toxic and Repellent Effects of Volatile Phenylpropenes from Asarum heterotropoides on Lasioderma serricorne and Liposcelis bostrychophila

Abstract

Toxic and repellent effects of the essential oil from <i>Asarum heterotropoides</i> Fr. Schmidt var. mandshuricum (Maxim.) Kitag. were evaluated against <i>Lasioderma serricorne</i> and <i>Liposcelis bostrychophila</i>. The essential oils (EOs) from roots (ER) and leaves (EL) of <i>A. heterotropoides</i> were obtained separately by hydrodistillation and characterized by gas chromatography-mass spectrometry (GC-MS) analysis. Major components of ER and EL included methyleugenol, safrole, and 3,5-dimethoxytoluene. Both ER and EL of <i>A. heterotropoides</i> showed certain toxicity and repellency against <i>L. serricorne</i> and <i>L. bostrychophila</i>. 3,5-Dimethoxytoluene, methyleugenol, and safrole were strongly toxic via fumigation to <i>L. serricorne</i> (LC₅₀ = 4.99, 10.82, and 18.93 mg/L air, respectively). Safrole and 3,5-dimethoxytoluene possessed significant fumigant toxicity against <i>L. bostrychophila</i> (LC₅₀ = 0.83 and 0.91 mg/L air, respectively). The three compounds all exhibited potent contact toxicity against the two insect species. Here, the EL of <i>A. heterotropoides</i> was confirmed to have certain toxicity and repellency against stored product insects, providing a novel idea for the comprehensive use of plant resources.