Chemical composition of Ricinus communis and Momordica charantia seeds extracts and its bioactivity against the sugarcane aphid, Melanaphis sacchari (Zehntner)

Melanaphis sacchari Zehntner (Hemiptera: Aphididae) is currently the most destructive pest insect of the sorghum crop (Sorghum bicolor L. Moench) and has caused economic losses worldwide. Strategies using natural products such as plant extracts can offer alternatives for the control of this pest. In this investigation, we evaluated the insecticidal effect of the hexane extract of Ricinus communis L. and Momordica charantia L. seeds on M. sacchari in contact bioassays. The results showed that the extract of R. communis presented a mortality rate of 100% in 48 h at 10,000 ppm, while M. charantia presented 80% in 72 h, at 10,000 ppm. Gas chromatography-mass spectrometry (GC-MS) identified the major compounds as squalene in R. communis (51.57%) and linalool oxide in M. charantia (30.45%). The hexanic extracts of these plant species could be considered an ecologically friendly alternative to control this pest, given the use of synthetic chemical insecticides.