Efficacy of the extract from pongam (Pongamia pinnata) leaves against the cassava pink mealybug (Phenacoccus manihoti Matile-Ferrero) under laboratory conditions

The cassava pink mealybug, Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae), a native of South America, have been one of the most serious pests of cassava (Manihot esculenta Crantz) in the world. Conventional control of this pest is dependent on synthetic chemical insecticides. This study was carried out at Entomology Laboratory, Faculty of Agronomy, University of Agriculture and Forestry, Hue University, Vietnam during 2020 - 2021 to determine the efficacy of leaf extract from Progamia pinnata against the cassava pink mealybug. The efficacy of pongam leaf extract was more efficacious against the first instar than the second instar of P. manihoti, and was according to the evaluation time. After ten days treatment, the efficacy of the leaf extract against first and second instars of P. manihoti was 100% and 50.0, 73.3, 66.7% at concentrations of 2.0, 1.8 and 1.4%, respectively. Therefore, pongam leaf extract can be recommended for protection of the cassava pink mealybug.