|Stark, John - Washington State University|
|Fox, Abbie - Animal And Plant Health Inspection Service (APHIS)|
|Smith, Trevor - Florida Department Of Agriculture And Consumer Services|
|Leblanc, Luc - University Of Hawaii|
Submitted to: Biopesticides International
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/30/2014
Publication Date: 12/31/2014
Citation: Stark, J.D., Vargas, R.I., Souder, S., Fox, A.J., Smith, T.R., Leblanc, L., Mackey, B.E. 2014. Simulated field applications of insecticide soil drenches for control of Tephritid fruit flies. Biopesticides International. 10(2):136-142.
Interpretive Summary: Annual introductions of Tephritidae fruit flies often result in temporary trade restrictions and associated area-wide eradication treatments, lasting up to 9 months before movement of agricultural commodities can resume without postharvest treatments. Although most of the fruit fly control efforts world-wide involve protection of food, nursery stock can also be affected due to quarantine restrictions. In California and Florida, quarantine regulations designed to prevent the movement of fruit flies from infested areas can impact the movement of fruiting nursery stock, large orchards, or even backyard growers. The nursery industry in California is one of the largest agricultural industries in the State, and ranks as one of the top five commodities in monetary value. At present, to ship fruit tree nursery stock out of the state, container pots with fruit seedlings and small trees must be drenched with diazinon prior to shipment. Although many uses of diazinon have been discontinued in the United States due to problems with its effects on aquatic organisms in freshwater ecosystems, it is still used in California via a Special Local Needs (SLN) registration. Diazinon is an organophosphate insecticide which has been banned for outdoor residential use by the U.S. Environmental Protection Agency. In California and Florida, alternative insectides for quarantine treatment of nursery stock and soil drenches in areas where fruit flies detections trigger application are needed to replace diazinon in the event that it is no longer available. The objective of this study conducted by the U.S. Department of Agriculture, Agriculture Research Service (USDA-ARS)was to evaluate several insecticides for their efficacy as controls of the larval and pupal stages of pest fruit flies in organic soil. The results of this study indicate that several insecticides are available to replace Diazinon as a soil treatment for orchard and back yard fruit tree drenches and in nursery containers against fruit flies.
Technical Abstract: A key component in tephritid fruit fly (Diptera: Tephritidae) area-wide IPM programs has been application of insecticidal soil drenches under the drip line of host trees where fruit flies have been detected and as a regulatory treatment in the certification process for movement of nursery stock outside of fruit fly quarantine areas. Diazinon has been the most effective and widely used insecticide for this purpose; however it is being phased out in many areas due to environmental issues. The objective of this study was to evaluate the efficacy of several insecticides as Diazinon replacements for control of three economically important fruit fly species, Mediterranean fruit fly, Ceratitis capitata, melon fly, Bactorcera cucurbitae, and oriental fruit fly, B.dorsalis using a semi-field approach. Fruit fly pupae that were ready to eclose within 24h were exposed to organic soil treated with Radiant SC (Spinetoram), Force 3G and Force CS (Tefluthrin); Warrior II (Lambda-cyhalothrin); the biopesticides, Entrust and Entrust SC (Spinosad); Gardstar 40% EC (Permethrin) or Diazinon AG 600. All alternative insecticides resulted in a significant reduction in adult emergence and were not significantly different from Diazinon. Insecticides that resulted in no adult emergence for C.capitata and B.dorsalis were Entrust SC, Warrior II, Gardstar, and Force CS, and for B.cucurbitae, Entrsut SC and Force CS. Late third instar larvae ready to pupate were exposed to organic soil treated with Force CS, Warior II, Entrust SC, Gardstar, or Diazinon AG 600. All alternative insecticides resulted in a significant reduction in adult emergence and were not significantly different from Diazinon. Insecticides that resulted in no adult emergence of C.capitata and B.dorsalis were Warrior II, Gardstar and Force CS. Insecticides that resulted in no adult emergence in B.cucurbitae were Gardstar and Force CS. Our results suggest several alternative insecticides to Diazinon, for control of late larval or pupal stages of three economically important fruit fly species.