Ovicidal Effect of the Ethanolic Extract of Moringa oleifera Leaf on Oligonychus punicae (Trombidiformes: Tetranychidae) Eggs1

Abstract

Mexico is the leader in avocado (Persea americana Miller [Lauraceae]) production, with the United States being the principal consumer of avocados produced there. The avocado crop is susceptible to attacks by insect and mite pests, including the avocado brown mite, Oligonychus punicae (Hirst) (Acari: Tetranychidae), which is a serious economic pest of the crop in Mexico. This study evaluated the effects of different concentrations (0.1, 0.5, 1, 5, 10, 15, and 20% [v/v]) of the ethanolic extract from Moringa oleifera Lamarck (Moringaceae) leaves against O. punicae eggs and its residual effect on the density of larvae and nymphs emerging from treated eggs. Egg mortality ranged from 0.0 at the 0.1% concentration to 70.48% at the 20% concentration, compared with the control group. Egg mortality increased as extract concentrations increased. The density of larvae and nymphs that emerged from the treated eggs was significantly lower than the density in the control, indicating that both the number of living larvae and nymphs responded to extract concentration. Our results support the suggestion that the ethanolic extract of M. oleifera leaf has ovicidal and residual activity against O. punicae and can be incorporated into an integrated mite management program to control avocado brown mite populations. Further studies are needed to assess the efficiency and efficacy of M. oleifera extract against arthropod pests and natural enemies under greenhouse and field conditions.