Insecticidal and attractant activities of magnolia citrata leaf essential oil against two major pests from diptera: aedes aegypti (culicidae) and ceratitis capitata (tephritidae)

Authors: LUU-DAM, NGOC ANH - Vietnam Academy Of Science And Technology (VAST); Tabanca, Nurhayat; Estep Iii, Alden; NGUYEN, DUY HUNG - Vietnam Academy Of Science And Technology (VAST); Kendra, Paul

Submitted to: Molecules
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/14/2021
Publication Date: 4/16/2021
Citation: Luu-Dam, N., Tabanca, N., Estep Iii, A.S., Nguyen, D., Kendra, P.E. 2021. Insecticidal and attractant activities of magnolia citrata leaf essential oil against two major pests from diptera: aedes aegypti (culicidae) and ceratitis capitata (tephritidae). Molecules. 26(8): 2311. https://doi.org/10.3390/molecules26082311.
DOI: https://doi.org/10.3390/molecules26082311

Interpretive Summary: Plant essential oils are the main source of bioactive natural products used to control agricultural insect pests and insect vectors of disease. Due to the deleterious effects of synthetic insecticides on the environment and human health, as well as the increase in pesticide resistance in insects, it is necessary to develop alternative control strategies to reduce the use of insecticides. Therefore, ARS scientists in Miami and Gainesville, FL, in collaboration with researchers from Vietnam, conducted research to evaluate the essential oil of Magnolia citrata Noot. & Chalermglin (Magnoliaceae) as a potential source of toxicants for the yellow fever mosquito Aedes aegypti and of attractants for Mediterranean fruit fly Ceratitis capitata. The M. citrata essential oil (MCEO) was analyzed by gas chromatography-mass spectrometry (GC-MS) and results indicated that oxygenated monoterpenoids constituted the largest contribution to the overall MCEO (78%), with an abundance of monoterpene hydrocarbons (17%). Primary bioassays found that MCEO had better larvicidal activity (100%) against Aedes aegypti first instar larvae whereas the oil showed only 50% mortality against adult Ae. aegypti. In bioassays with male C. capitata, MCEO displayed moderate attraction compared to the positive control (tea tree oil). Further studies are needed to determine the specific chemical constituents responsible for larvicidal activity against Ae. Aegypti larvae, attractant activity for adult C. capitata, and potential synergistic effects of MCEO when combined with other known bioactive natural products. Results of this study may contribute to development of improved environmentally sound strategies for control of major economic pests within the Diptera.

Technical Abstract: In this study, Magnolia citrata Noot. & Chalermglin (Magnoliaceae) essential oil (MCEO) was evaluated for insecticidal activity against the yellow fever mosquito Aedes aegypti and attractant activity for the Mediterranean fruit fly Ceratitis capitata. The leaves of Magnolia citrata (Giô'i chanh) were collected from northwestern Vietnam and the water-distilled MCEO was analyzed by gas-chromatography and mass spectrometry (GC-MS). The major constituents of MCEO were identified as linalool 19%, geranial 16%, citronellal 14%, neral 14%, and sabinene 12%. MCEO showed 100% mortality at 1 ug/uL against 1st instar larvae of Ae. aegypti (Orlando strain, ORL) and the oil exhibited 54% (ORL) and 68% (Puerto Rico strain) mortality at 5 ug/mosquito against Ae. aegypti adult females. Initial screens showed that MCEO had weak insecticidal activity compared to the positive control permethrin. In bioassays with sterile male C. capitata, MCEO exhibited moderately strong attraction, comparable to that observed with a positive control, Tetradenia riparia essential oil (TREO). Herein the insecticidal and attractant activities of MCEO are reported for the first time.