Evaluation of different natural enemies for biological control of Aphis nerii and Myzus persicae on Mandevilla
Abstract: Mandevilla is a genus of plants of the Apocynaceae family, widely appreciated by
the floriculture market for several aesthetic and agronomic characteristics. During cultivation, various pests can infest Mandevilla, and the management of the aphids Aphis nerii (Boyer de Fonscolombe) and Myzus persicae (Sulzer) can be particularly challenging because of the limited effect of chemical and biological control tactics. In particular, A. nerii can sequester cardenolides produced by Mandevilla, potentially impacting biological control programs. Identifying natural enemies that can prey on this aphid and overcoming the resistance due to cardenolide sequestration is the first step in developing a biological control program. In laboratory and semi-field experiments, we evaluated the performances of different natural enemies in suppressing populations of Aphis nerii and Myzus persicae, on Mandevilla. Promising results were obtained with Sphaerophoria rueppellii (Wiedemann)and Micromus angulatus (Stephens) that were able to prey and reduce the populations of the two aphid species under laboratory and semi-field conditions. Other natural enemies did not show a significant effect in the predation of the aphids and reduction of their populations. With a perspective of IPM and reducing pesticide use on protected crops, this study demonstrated the potential of two predators for their use in biological control of two aphid pests on Mandevilla.