Chemical constituents of essential oil extracted from Rhododendron anthopogonoides and its bioactivities against Tribolium castaneum and Ditylenchus destructor

Essential oils (EOs) extracted from botanical resources have greatly been appraised as insecticides against a broad spectrum of pre-and postharvest pests and pathogens. This study aimed to investigate the chemical constituents of the EO from Rhododendron anthopogonoides and the biological activity of EO and its main com-pound against Tribolium castaneum and Ditylenchus destructor. A total of 14 compounds were identified, and the main components of EO from R. anthopogonoides were 4-phenyl-2-butanone (47.73%), eudesma-3,7(11)-diene (14.52%), curzerene (9.5%), 4-phenylbutan-2-ylacetate (6.43%), beta-cadinene (5.79%), and germacrone (5.73%). The results of bioassays indicated that the EO oil of R. anthopogonoides possessed obvious contact ac-tivity (LD50 = 9.83 mu g/adult) and repellent activity against T. castaneum. The indoor toxicity indicated that the R. anthopogonoides EO and its main constituent 4-phenyl-2-butanone possessed strong nematicidal activity against D. destructor (LC50 = 0.21 and 0.04 mg/mL). These results provided the theoretical basis for controlling T. castaneum and D. destructor using the EO from R. anthopogonoides.