Managing Macrosteles near Severini (Auchenorrhyncha: Cicadellidae) and Myzus persicae (Hemiptera: Aphididae) in Florida watercress.
This is the first report of Macrosteles near severini Hamilton (Auchenorrhyncha: Cicadellidae), an invasive leafhopper, in Florida. The leafhopper was first detected in watercress in Florida in 2014. This leafhopper transmits the phytoplasma watercress aster yellows, which can cause significant yield losses. Insecticide trials were carried out in the spring of 2014 to compare the efficacy of buprofezin, flonicamid, flupyradifurone, sulfoxaflor, and tolfenpyrad, none of which were registered for use on watercress at the time of testing, with the grower standards of imidacloprid and spirotetramat, for management of M. nr. severini. All treatments except flonicamid resulted in statistically lower numbers of leafhopper nymphs than the untreated control after 3 or fewer applications. Efficacy data from this trial was provided in support of the registration of sulfoxaflor for watercress. Buprofezin and tolfenpyrad also demonstrated efficacy, and each possesses a mode of action that is distinct from imidacloprid and spirotetramat. In addition, flonicamid, sulfoxaflor, and tolfenpyrad demonstrated efficacy against Myzus persicae (Sulzer) (Hemiptera: Aphididae), an aphid pest of watercress.