Hautriwaic acid isolated from <i>Dodonaea viscosa</i> leaves exhibits insecticidal activity against the sorghum aphid, <i>Melanaphis sorghi</i>

The sorghum aphid, Melanaphis sorghi Theobald, 1904 (Hemiptera: Aphididae), is one of the main pests of sorghum ( Sorghum bicolor L. Moench, Poaceae) in Mexico. Its control relies primarily on synthetic insecticides, although more sustainable alternatives using plant-derived extracts and compounds have been explored. In this study, we evaluated the insecticidal activity of Dodonaea viscosa leaves using a sequential approach. Initially, a crude acetone extract of Dodonaea viscosa (EADv) was prepared and subsequently fractionated (DvF1–DvF5) based on chemical composition; from the most active fraction, we isolated a pure diterpene, hautriwaic acid. Results showed that EADv achieved 76% mortality at 2,500 Parts per million (ppm) after 72 h. Among the fractions, DvF3 exhibited the strongest activity with 92% mortality and a median lethal concentration (LC 50 ) of 414.9 ppm at 72 h. The hautriwaic acid isolated from DvF3 was even more effective, causing 96% mortality at 50 ppm and an LC 50 of 43.79 ppm at 72 h. These findings demonstrate that D. viscosa contains compounds with significant insecticidal activity against M. sorghi , highlighting hautriwaic acid as a potent insecticidal agent at low concentrations, making it a promising alternative for integrated pest management in sorghum.