Cistus monspeliensis L.: Antioxidant potential, in-Vitro and in-situ evaluation of the insecticidal activity against Aphis gossypii Glover

This study investigates the antioxidant and insecticidal efficacy of Cistus monspeliensis aqueous extracts against Aphis gossypii infesting Citrus orchards in Laboratory and natural conditions. Leaves of C. monspeliensis were collected from Djebel Zaghouan (Tunisia). The extracts revealed moderate levels of polyphenols (76.06 mg GAE/g DW), flavonoids (15.47 mg QE/g DW), and condensed tannins (10.88 mg CE/g DW), and showed significant antioxidant capacity with an IC50 value of 96.93 µg/mL for the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. In-vitro insecticidal activity assays showed that the efficacy rates were 51.4%, 52.9%, and 44.5% for 10%, 5%, and 2.5% concentrations, respectively, indicating a dose-dependent increase in mortality and insecticidal effect. Field trials revealed that the application of C. monspeliensis extracts at 50 g/L significantly reduced aphid populations, with corrected mortality rates of 53.5% at T2 + 168 h (branch sampling) and 54.25% at T2 + 168 h (Japanese umbrella method). These results suggest that C. monspeliensis extracts can serve as an effective component of integrated pest management strategies against citrus aphids, providing a sustainable alternative to synthetic insecticides.