Effect of the Biological Control Agent Neoseiulus californicus (Acari: Phytoseiidae) on Arthropod Community Structure in North Florida Strawberry Fields

Abstract

Field experiments were conducted during the 2006-2007 growing season to determine the effect of the predatory mite, Neoseiulus californicus (McGregor) on arthropod community structure when released as a biological control agent for the twospotted spider mite, Tetranychus urticae Koch, in north Florida strawberries (Fragaria × ananassa Duchesne). Releases of N. californicus were conducted at approximately 1-month intervals from Dec 2006 to Feb 2007 to compare effects of predator release times on arthropod community structure. Evaluations of community structure were conducted 3 times during the growing season. The Shannon-Weaver index of diversity was used to quantify differences among release and non-release plots. Our results indicate that the release of N. californicus does not affect the arthropod diversity in the strawberry system studied. The generalist feeding behavior of N. californicus, coupled with a high level of richness and diversity in the strawberry ecosystem, may diffuse the measurable effect of N. californicus releases on the arthropod community structure. This makes N. californicus a desirable biological control agent for management of twospotted spider mite in strawberries while preserving arthropod diversity.