Location: Subtropical Horticulture Research2011 Annual Report
1a. Objectives (from AD-416)
The long-term objective of this project is to develop trapping and control components and systems for integrated pest management of exotic pest insects in the Caribbean, Central and South America that pose a threat to U.S. agriculture.
1b. Approach (from AD-416)
Research will consist of field and laboratory studies to determine the life history, distribution and host range of exotic insect pests; to identify semiochemicals; and to conduct studies on the behavioral and physiological roles of semiochemicals on these pests and associated biocontrol organisms. Strategies will include development of attractant-based technologies and systems for detecting, delimiting and monitoring exotic pest insects, and for establishing and enhancing management programs for these insects.
3. Progress Report
Field test of mass trapping and bait stations for caribfly population suppression. The third year of an ongoing study tested a new version of a caribfly bait station that is being produced using newly developed small scale production method by Animal Plant Health Inspection Service (APHIS) collaborators in Guatemala using the wax matrix developed by ARS scientists in Miami, FL. As was observed in previous years, the greatest suppression of adult fly numbers was obtained in the mass trapping treatment, and fruit from that block had the lowest level of larval infestation. The block with the improved bait station also had fewer adults trapped than the untreated control, but larval infestation was not reduced. Response of sterile male medflies to rasped bark from lychee cultivars. Initial studies found a strong attraction of sterile male medflies to volatile chemicals from bark rasped from a lychee cultivar. Therefore, ARS scientists conducted research to evaluate medfly response and to chemically analyze 15 lychee varieties that are part of the plant collection maintained at the Miami, FL location. There are significant differences in both the attraction of medflies and volatile chemistry among the varieties. This information will be used to direct bioassays using synthetic chemicals to identify the chemicals responsible for the medfly attraction. Behavior of male medflies in response to exposure to plant essential oils. Studies were continued to test response of medflies to plant essential oils, including a new commercial formulation not tested previously. Laboratory bioassays using sterile males were used to quantify effects on medfly behavior, including short-range attraction. Long-range attraction was tested with field studies that were conducted in Honduras under a Specific Cooperative Agreement to test response of wild medflies. Chemical analysis coupled with electroantennogram analysis is ongoing to identify semiochemicals responsible for medfly response. Host preferences of the redbay ambrosia beetle in Florida. As part of research to identify host-based attractants for the redbay ambrosia beetle (RAB), the vector of laurel wilt disease, comparative studies were initiated with the dominant species of Lauraceae that occur in south Florida. Field tests and laboratory bioassays were conducted with freshly-cut branches of host wood to determine relative attraction and boring behaviors (host recognition/acceptance) of RAB to avocado, redbay, swampbay, silkbay, camphor tree, and lancewood. Comparative analysis of wood volatiles from host trees is being used to identify the specific chemicals responsible for attraction of female RAB.
1. Improved detection system for the redbay ambrosia beetle. The redbay ambrosia beetle (RAB) vectors Laurel Wilt, a lethal disease of avocado and other U.S. trees in the Lauraceae. The standard trapping system for RAB has been Lindgren funnel traps baited with commercial phoebe or manuka oil lures. Per manufacturer specifications, the lures are used for two months before replacement. ARS scientists at Miami, FL, conducted field tests at two sites in Florida to evaluate efficacy and longevity of these two essential oil lures when deployed in funnel traps and sticky traps. Phoebe lures captured significantly more RAB than manuka lures, and sticky traps captured more RAB than funnel traps over 10-12 weeks. However, manuka lures were as effective as phoebe lures during the first 2-3 weeks of field use. This information is being used by action agencies (Florida Division of Plant Industry and Cooperative Agriculture Pest Survey [CAPS]) to improve detection of RAB. Unfortunately, supplies of phoebe lures have been depleted, and they are no longer available commercially. Therefore, action agencies now replace the manuka lures every 2 weeks and have added the more effective sticky panels for their monitoring programs.
2. Comparisons of trap and lure combinations for caribfly capture. At the request of APHIS, ARS scientists at Miami, FL, conducted field tests to compare capture of caribflies with two traps used for capturing medflies (McPhail-type traps and open-bottom dry traps). Traps were tested with the caribfly-targeted two component food-based lure and the medfly-targeted three component food-based lure. McPhail-type traps baited with the two or three component lure captured the highest and second highest number of caribflies, respectively. However, few caribflies were captured in the open-bottom dry traps, no matter which lure was used. This study showed that caribfly prefer the McPhail-type traps no matter which food-based lure was used.
Kendra, P.E., Roda, A.L., Montgomery, W.S., Schnell, E.Q., Niogret, J., Epsky, N.D., Heath, R.R. 2011. Gas chromatography for detection of citrus infestation by fruit fly larvae (Diptera: Tephritidae). Postharvest Biology and Technology. 59:143-149.