Use of Amblyseius swirskii for biological control of broad mites in high-tunnel pepper production in Florida

Amblyseius swirskii (Athias-Henriot) is a predatory mite used by Florida growers to control major pests such as thrips, whiteflies, and broad mites. However, there is a lack of information concerning the use of banker plants to optimize biological control of pests using this phytoseiid under high-tunnel pepper production. Dispersal capacity of A. swirskii, using the ornamental pepper 'Explosive ember' as banker plant, was evaluated for control of broad mites in high-tunnel peppers. Plants at two age stages, five and ten-week-old (open vs closed canopy), were used to evaluate the effect of plant connectedness in A. swirskii dispersal, in presence (two females/plant) and absence of P. latus. Plots consisted of single rows of nine plants, one flowering banker plant in the center and four bell peppers linearly extending north and south. On days 1, 4, or 7 after releasing A. swirskii under the tunnel, plants were destructively sampled. The experiments were repeated four times between November 2013 and March 2014. Amblyseius swirskii dispersed from the banker plants to neighboring bell peppers plants at all positions and all treatments within 24 hours. More predatory mites were recorded in bell peppers with a closed canopy regardless the presence of broad mites. Relationships between numbers of A. swirskii, broad mites, and alternative prey (such as whiteflies) were found only in two of the experiments.