First report of Zaprionus indianus (Diptera: Drosophilidae) in commercial fruits and vegetables in Pennsylvania.

Zaprionus indianus (Gupta) (Diptera: Drosophilidae), an invasive vinegar fly, was found for the first time in Adams County, Pennsylvania, in 2011. It was found in a commercial tart cherry orchard using apple cider vinegar (ACV) traps that were monitoring another invasive vinegar fly, the spotted wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae). Coincidentally, the first record of D. suzukii found in Pennsylvania was also found in this same cherry orchard only 3 months earlier as part of a spotted wing drosophila survey effort in raspberry, blackberry, grape, and tart cherry in Adams County. These same crops plus blueberry and tomato were monitored again in 2012. In this article, adult Z. indianus captures in ACV traps and other traps deployed in the aforementioned crops during 2012 season are presented and the economic importance of Z. indianus is discussed.

Evaluation of cultural practices for potential to control strawberry sap beetle (Coleoptera: Nitidulidae).

Strawberry sap beetle, Stelidota geminata (Say) (Coleoptera: Nitidulidae), adults and larvae feed on and contaminate marketable strawberry (Fragaria L.) fruit. The beetle is a serious pest in the northeastern United States, with growers in multiple states reporting closing fields for picking prematurely due to fruit damage. Three options were evaluated for potential to reduce strawberry sap beetle populations. First, the influence of plant structure on accessibility of fruit in different strawberry cultivars to strawberry sap beetle was assessed by modifying plant structure and exposing caged plants to strawberry sap beetle adults. Severity of damage to berries staked up off the ground was similar to damage to those fruit contacting the soil, showing that adults will damage fruit held off the ground. Second, baited traps were placed at three distances into strawberry fields to determine whether overwintered beetles enter strawberry fields gradually. Adult beetles were first caught in the strawberries approximately equal to 19 d after occurring in traps placed along edges of adjacent wooded areas. The beetles arrived during the same sampling interval in traps at all distances into the fields, indicating that a border spray is unlikely to adequately control strawberry sap beetle. Third, the number of strawberry sap beetle emerging from strawberry for 5 wk after tilling and narrowing of plant rows was compared in plots renovated immediately at the end of harvest and in plots where renovation was delayed by 1 wk. In the 2-yr study, year and not treatment was the primary factor affecting the total number of emerging strawberry sap beetle. Overall, limited potential exists to reduce strawberry sap beetle populations by choosing cultivars with a particular plant structure, applying insecticide as a border spray, or modifying time of field renovation.

Evaluation of strawberry sap beetle (Coleoptera: Nitidulidae) use of habitats surrounding strawberry plantings as food resources and overwintering sites.

The matrix of strawberry and alternate host crops, wooded areas, and uncultivated sections that comprises a farm landscape provides not only food resources but also habitat in both a spatial and temporal context. Reports of the strawberry sap beetle as a pest in strawberry in the northeastern United States have increased along with a trend to produce a wider diversity of fruit crops on individual farms. The three objectives of this study focused on determining which, if any, habitats outside strawberry plantings are important to consider when developing control strategies for strawberry sap beetles. First, sampling of wooded areas and multiple crops showed that strawberry sap beetles overwinter not only in wooded areas but also in blueberry and raspberry. No overwintering beetles were found in strawberry. Second, up to a 70-fold increase in mean number of strawberry sap beetles in a no-choice food source experiment indicated that considerable reproduction can occur on blueberry, cherry, raspberry, and strawberry. Third, sampling summer-bearing raspberry, peach, blueberry, and cherry in 2004 and 2005 confirmed that beetles were present, often in high densities (0.1-108.5 strawberry sap beetles/m(2)), in commercial fields with fruit or vegetable material on the ground. In summary, the beetles are able to feed, complete development, and overwinter in habitats other than strawberry. An effective integrated pest management program to control strawberry sap beetles will need to consider the type of habitat surrounding strawberry fields.