2019 ASHS Annual Conference

The ideal climate for strawberry (Fragaria x ananassa Duch.) production is in California. The rest of the country, including the mid-south, grow only a small portion of strawberries in the United States. Consumer demand for organic, locally grown food has increased within the past few years. However, organic, small-scale producers in the mid-south face abiotic and biotic factors that affect production and fruit quality such as rain, disease and arthropods. These problems make organic production, while trying to meet consumer demands, almost impossible to accomplish. One solution to these problems includes the use of high tunnel technologies, which have increased in popularity with small-scale growers. Tunnels provide some protection from the environment, while creating a microenvironment inside of the tunnel. However, some pests such as Tetranychus urticae (two-spotted spider mites), Chaetosiphon fragaefolii (strawberry aphids), Podosphaera aphanis (powdery mildew) and Botrytis cinerea (gray mold) can thrive in the high tunnel. Because of these pests, organic growers look for a solution in sustainable pesticides such as biopesticides. Little research has been conducted to determine the efficacy of biopesticides for strawberries in high tunnels. In 2017, the cultivars Sensation and Camino Real were planted as an annual plasticulture system in a Quonset-style Grow Span high tunnel located at the UA Research and Extension Center in Fayetteville, Arkansas. Six combinations of biological fungicides and insecticides were selected as the treatments based on grower’s needs. The objective of this study is to evaluate the efficacy of the different treatments to determine how these combinations affect yield, diseases and arthropods. A regular spray schedule was followed with data collected during the months between February and May. This study determine that the treatment combinations had a significant effect in marketable, unmarketable and total fruit yield. Cultivar and date had a significant effect on the mean number of Two-spotted spider mites per leaf, indicating that Camino Real had significantly higher infestations than Sensation. The treatment combinations also showed a significant effect in the number of Two-spotted spider mites per leaf; although all treatments were above the economic threshold of 5 mites per leaf. The percent damage of gray mold indicated that the treatment combinations have a different effect on the two cultivars. The treatment combination of Regalia, Grandevo and Cueva had the greatest disease incidence with Camino Real and the lowest disease incidence with Sensation.