Andress E.,U.S. Department of Agriculture |
Jones E.,U.S. Department of Agriculture |
War M.,CDFA |
Shelly T.,U.S. Department of Agriculture
Florida Entomologist | Year: 2012
The Sterile Insect Technique (SIT) is used to suppress or eradicate infestations of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann). The success of the SIT depends to a large degree on the ability of sterile males to compete successfully against wild males in obtaining matings with wild females. Sterile males are chilled to allow their transfer to and subsequent storage within the aircraft used for the releases. Here, we describe the results of an experiment that investigated the effects of varying chill duration (at 38 °C for 26 h) on flight ability of sterile males derived from mass-rearing facilities in Hawaii and Guatemala. Flight ability decreased significantly, and at the same rate, with increasing chill duration for flies from both production facilities. However, for any given chill duration, the Hawaii-derived flies displayed greater flight ability than the Guatemala-derived flies. In addition, there was significant variation in flight ability among daily shipments from both facilities. Nevertheless, the present data clearly reveal that limiting chill duration promotes higher flight performance of released sterile males. Implications of our findings for Mediterranean fruit fly SIT programs are discussed.
Shelly T.,U.S. Department of Agriculture |
Renshaw J.,U.S. Department of Agriculture |
Dunivin R.,U.S. Department of Agriculture |
Morris T.,U.S. Department of Agriculture |
And 6 more authors.
Florida Entomologist | Year: 2013
Invasive species of Bactrocera fruit flies (Diptera: Tephritidae), particularly B. dorsalis (Hendel) and B. Cucurbitae (Coquillett), pose serious threats to agricultural crops. Detection relies largely on traps baited with the male lures methyl eugenol (ME), which is attractive to B. dorsalis, and cue-lure (CL) or the related chemicals raspberry ketone (RK) and raspberry ketone formate (RKF), which are all attractive to B. Cucurbitae. Currently, ME and CL are applied as liquids to cotton wicks (along with an insecticide), a procedure involving considerable handling time and exposure to pesticides. Recent studies have shown that traps baited with solid dispensers (plugs or wafers) of male lures, which arrive in sealed envelopes ready for use, catch at least as many Bactrocera males as traps baited with liquid lures. The present study compared captures of B. dorsalis and B. Cucurbitae males in traps baited with liquid lures versus traps baited with lure-bearing solid dispensers in Florida, California, and Hawaii. In the first 2 locations, marked, irradiated males were released at street intersections, and captures were scored at 4 trapping stations 50 m distant along the intersecting streets with various lure/dispenser combinations. In Hawaii, trap catch of wild B. dorsalis and B. Cucurbitae were compared among traps with liquid and solid formulations of the lures. Although several exceptions were observed, the overall finding was that the lure-bearing plugs and wafers captured as many or more Bactrocera males as the liquid application. Consequently, we suggest that solid dispensers could be adopted in area-wide fruit fly surveillance programs without lessening their detection sensitivity to incipient infestations. The use of solid dispensers that contain both ME and RK, in particular, could greatly reduce the number of traps required and result in considerable cost savings.