Location: Subtropical Horticulture Research2009 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
Improved formulation of bait stations for fruit flies control. Research was conducted that increased the amount of chemical attractant and the longevity of chemical release from wax matrix attract-and-kill systems (bait stations) developed at the station. Field tests found that the bait stations remained attractive for at least six months and a change in the type of coloring used to add a visual cue prevented discoloration during storage and also provided increased color stability in the field. Both the chemical attractant and the color are important for efficacy of bait stations for fruit fly control. Fruit fly antennal response to the fruit fly lure putrescine. Research was conducted to measure antennal olfactory response of caribflies to commercial putrescine lures. Antennal response was correlated with female physiological state and with behavioral response in flight tunnel bioassays. Immature females have a stronger response to ammonia bicarbonate but mature females have a stronger response to putrescine. Bioassays found that addition of putrescine to ammonia bicarbonate increased female-biased attraction of caribflies. This study is part of ongoing research to optimize monitoring programs used by action agencies for early detection of invasive fruit fly pests. Fruit fly antennal response to 3-methyl-1-butanol. Scientists found that 3-methyl-1-butanol (MB) is attractive to female caribflies in laboratory bioassays. Research was conducted to quantify caribfly antennal response to MB, including male and female dose response curves, potential additive effects with known attractants, and effect of female physiological state an antennal response. MB is a volatile chemical emitted from bacteria, a food source for adult fruit flies. This research will add to our knowledge on fruit fly attractants and development of improved trapping systems. Field tests to compare effectiveness of standard fruit fly baits for capture of caribflies. Field trials that were conducted in two caribfly host tree plantings determined the relative capture of caribflies in these different fruit fly trapping systems. Traps baited with the two component food-based synthetic attractant developed by station scientists captured the most caribflies, but there was no difference in capture in traps baited with either the food-based synthetic attractant used for medflies or with the liquid protein attractant also used for caribflies. The lowest capture was in traps baited with the liquid protein attractant used for medflies. Development of artificial diet for the pest weevil, Myllocerus undecimpustulatus undatus. The Myllocerus weevil causes heavy damage to foliage in landscape plantings and is becoming a pest of citrus as it moves into counties in Florida that were previously weevil-free. Ability to rear this weevil on artificial diet is needed for development of a semiochemical-based trapping system; however, there is poor larval survival on available artificial diets. Studies were conducted to test modifications to the diet and rearing environment for improved ability to rear this weevil, which would provide the numbers needed for subsequent research.
1. Determination of effective sampling range of food-based attractants for capture of medflies and caribflies. Sampling range, i.e. the maximum distance from which an insect can reach an attractive source in a given period of time, is an important aspect of trap efficacy. Release/recapture studies using sterile or fertile fruit flies insects have been used traditionally to determine sampling range. However, response of these flies to food-based attractants may not be directly applicable to response of wild flies due to differences in nutritional background. Studies were conducted in Honduras and in south Florida to test a geostatistical approach that used high density trapping grids to estimate sampling range from field-collected medflies and caribflies, respectively. These estimates were compared with those obtained from release/recapture studies. The results of these studies determined the sampling range for traps baited with food-based synthetic attractants used for these fruit flies. This information will be used by regulatory agencies, growers and researchers to determine coverage of traps used for population delimitation, for implementation of mass trapping control strategies, to pin-point areas of infestation for precision targeting of control measures, and to determine the minimum distance between treatments to avoid trap interference in field tests. This research will lead to improved suppression of fruit fly pests in areas with these pests, which will result in improved crop production and reduce threat to areas that are currently fly-free.
Amarasekare, K.G., Chong, J., Epsky, N.D., Mannion, C. 2008. Effect of Temperature on the life history of the mealybug, Paracoccus marginatus (Hemiptera: Pseudococcidae) under laboratory conditions. Journal of Economic Entomology 101(6):1798-1804.