Arthropod pest management on organic strawberries in Florida

This study was part of a larger project designed to improve organic strawberry production in the southeastern US. The focus of this study was on arthropod pest management. The twospotted spider mite (TSM), Tetranychus urticae Koch, is a major pest arthropod of a wide range of agricultural and ornamental plants, including strawberries. Spotted wing drosophila, Drosophila suzukii (Matsumura), is a recently introduced pest of soft-skinned fruits. Females possess a serrated ovipositor that allows them to lay their eggs in ripening and ripe fruit. One larva can cause an entire shipment of berries to be rejected. The specific objectives of this study were to 1) assess the susceptibility of three strawberry cultivars, ‘Festival’, ‘Sensation’, and ‘Winterstar’ to TSM infestation, 2) assess the efficacy of the predatory mite Neoseiulus californicus for managing TSM on two organic farms, 3) monitor the population of SWD on both farms, and 4) evaluate OMRI approved insecticides for SWD management. The study was conducted on two organic farms in north-central Florida. Farm 1 was heavily managed while the farm 2 was not. The three varieties were equally susceptible to mites. The TSM populations on both farms remained low until early March. Populations of N. californicus increased in March as well and kept the TSM population from exploding. On farm 1, few SWD were caught until March and most of the SWD were females. On farm 2, SWD were caught beginning in January. Both males and females were collected indicating a well established population. Veretran-D caused as much mortality to SWD as Entrust.