Location: Horticultural Crops Research2011 Annual Report
1a. Objectives (from AD-416)
Objective 1: Employ semiochemicals to enhance the monitoring and management of Otiorhynchus sulcatus and Drosophila suzukii as well as to manipulate their natural enemies. Objective 2: Develop integrated pest management tools for key pests of ornamental nursery and small fruit crops. Objective 3: Address invasive and reemerging arthropod pests of nursery and small fruit crops.
1b. Approach (from AD-416)
The bionomics and the chemical ecology of economically-important insect pests of nursery and small fruits crops will be studied in the field and under controlled conditions of temperature, humidity, and light in growth chambers and greenhouses. Emphasis will also be placed on understanding the ecology of the microbial control agents of these pests in the laboratory greenhouse and field. Together, the information compiled on the ecology of the pests and their respective microbial control agents will be integrated to begin development of biologically-based pest management programs.
3. Progress Report
This report documents progress for Project Number 5358-22000-037-00D, entitled “Integrated Pest Management for Insect Pests of Horticultural Crops,” which started 02/22/2011, and continues research from Project Number 5358-22000-032-00D, entitled “Development of Biologically-Based Strategies for Managing Insect Pests of Horticultural Crops.” To determine the most effective trap in combination with attractive semiochemicals for capturing O. sulcatus adults, replicated field studies were performed with a variety of experimental trap designs. We were able to identify a trap design that successfully captured a large proportion of the weevils in the field. This design will be refined to maximize capture rates. To determine the efficacy of methyl salicylate (MeSA), an herbivore-induced plant volatile, for attracting natural enemies into fields, we completed 2nd year trials in Alberta spruce container yards and bare-root red maple fields. The inconsistent response of natural enemies to MeSA alerted growers to focus on other pest control options and researchers to focus on understanding the behavioral responses of natural enemies at a finer scale. To clarify the role of raspberry aphids in vectoring viruses to raspberries, we monitored aphid feeding patterns on susceptible and resistant raspberry plants, their developmental times under a variety of temperatures and outdoors, and population trends in raspberry fields. These observations will enable growers to improve timing of treatments for aphids to reduce virus spread. To determine the rhizosphere competence of the commercial isolate of M. anisopliae, inoculated cuttings were planted in fungal treated and control soils. Plants were then evaluated for rhizosphere colonization. To date, the rhizosphere of a wide variety of ornamentals are colonized with the insect killing fungus. To determine the efficacy of a predatory mite to control black vine weevil, we completed laboratory assays confirming that Stratiolaelaps scimitus would feed on neonate weevil larvae. This potential biological control option is important to natural enemy suppliers and greenhouse growers. To better understand the new invasive spotted wing drosophila, we conducted studies on the susceptibility of different ripeness stages of small fruits, cultivars and ornamental hosts, their spring time activity, and the efficacy of the predatory minute pirate bug. We have also placed traps in the field to develop monitoring strategies and treatment thresholds. These results have been used to develop revised management guidelines in 2011.
1. Susceptibility of small fruits to spotted wing drosophila. The spotted wing drosophila is a new invasive fly that is threatening the small and stone fruit industry, particularly in the western states. Unlike other drosophila flies, this species can infest undamaged fruit that is still on the plant leading to rejections of harvested fruit. ARS scientists in Corvallis, Oregon, with collaborators at the University of California and Oregon State University have determined that small fruits and cherries were mainly susceptible at the color-changing stages, no cultivars appeared strongly resistant, and table and wine grapes were not as susceptible based on laboratory assays. This information is now published, and has been used to refine management guidelines in 2011 for timing control treatments.
Walsh, D., Bolda, M., Goodhue, R., Dreves, A., Lee, J.C., Bruck, D.J., Walton, V.M., O'Neal, S.D., Zalom, F.G. 2011. Drosophila suzukii (Diptera: Drosophilidae): Invasive pest of ripening soft fruit expanding its geographic range and damage potential. Integrated Pest Management. 106(2):289-295.