Evaluation of Clematis flammula (Ranunculaceae) to control Phthorimaea absoluta (Lepidoptera: Gelechiidae)

Abstract: The attack of tomato crops by the invasive Phthorimaea absoluta (Meyrick, 1917),
formerly known as Tuta absoluta (Lepidoptera: Gelechiidae), has worsened since it spread
outside its endemic region. To develop a botanical insecticide six plants have been screened.
Of those, Clematis flammula had the highest effect and was thus chosen for further research.
First, we determined in the laboratory the lethal effect of the plant extract at different
concentrations: 0.05 mg/ml, 0.1 mg/ml, 0.25 mg/ml, 0.5 mg/ml. A total of 320 L3 larvae were subjected to the test. Lethal concentrations were determined as follows: LC25: 0.017 mg/ml, LC50: 0.216 mg/ml, and LC90: 26.822 mg/ml. Next, the efficacy of C. flammula aqueous extract was evaluated under field conditions by determining the proportion of the leaflet area affected by P. absoluta larvae. Three extract concentrations (25 mg/ml, 50 mg/ml, 0.1 g/ml) with positive and negative controls (Emma Gold insecticide + water) were applied. Finally, phenolic compounds in the extract were analyzed by high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD). Five compounds were detected: (1) Caffeic acid, (2) Ferulic acid, (3) Hesperedin, (4) trans cinnamic acid, (5) Apigenin. The results support the importance of plants and their effects on P. absoluta under laboratory and field conditions.