Friday, October 12, 2012: 7:40 AM
Hall 4E/F (WSCC)
Diversified agricultural systems have shown promising benefits for increasing biodiversity and ecosystem services. Integrating knowledge of relationships between regional and local vegetation and pest suppression can improve pest management in agroecosystems. The Western tarnished plant bug, Lygus hesperus (Hemiptera: Miridae), has been studied in strawberry systems to minimize fruit damage caused by this pest. This study contributes to this literature by investigating the relationships between regional and local heterogeneity and L. hesperus pest suppression in organic strawberry farms in Central Coast California. Five certified organic strawberry monoculture farms in an agriculturally intensive landscape and five certified organic polyculture strawberry farms surrounded by much natural habitat will be compared to measure effectiveness of some L. hesperus natural enemies, pest pressure, and pest damage. Surrounding landscape was characterized using ArcGIS 10.0. We will measure Peristenus relictus (Hymenoptera: Braconidae) parasitoid wasps and generalist predator Geocoris (big-eyed bug) species abundances using two methods: inducing emergence of parasitoids from collected L. hesperus nymph samples and collecting Geocoris species from strawberry plants using the plant “beating” method. We will also quantify L. hesperus damage to strawberries in each study site using selected pick plots. We expect that sites with more vegetative diversity will support more natural enemies to pests and therefore, fewer L. hesperus pests should be present and less pest damage should occur in the more heterogeneous study sites.