|SRIMARTPROM, M - Kasetsart University|
|BURIKAM, I - Kasetsart University|
|LIMOHPASMANEE, W - Institute Of Nuclear Technology|
|KONGRATARPORN, T - Institute Of Nuclear Technology|
|THANNARIN, T - Institute Of Nuclear Technology|
|BUNSIRI, A - Kasetsart University|
Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/2017
Publication Date: 2/4/2018
Citation: Srimartprom, M., Burikam, I., Limohpasmanee, W., Kongratarporn, T., Thannarin, T., Bunsiri, A., Follett, P.A. 2018. Low-dose irradiation with modified atmosphere packaging for mango against the Oriental Fruit Fly (Diptera: Tephritidae). Journal of Economic Entomology. 111(1):135-140.
Interpretive Summary: Irradiation is commonly used to disinfest the quarantine pest oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera:Tephritidae), on mango fruits before export from Thailand to foreign markets. Modified atmosphere packaging (MAP) used during export of mangoes creates a low oxygen environment that may reduce the efficacy of irradiation against B.dorsalis. USDA APHIS restricts the use of MAP creating <18% O2 for foreign countries exporting fruit to the U.S. using irradiation. Studies were conducted with 3 commercial MAP bags to determine if the oriental fruit fly in Thai mangos survives irradiation treatment better in MAP. MAP had no effect of the efficacy of irradiation against oriental fruit fly. Results suggest the USDA APHIS restriction on the use of MAP due to the low oxygen environment it creates may be unwarranted.
Technical Abstract: Irradiation and vapor–heating treatments are commonly used to disinfest the Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera:Tephritidae), and other pests on mango fruits before export from Thailand to foreign markets. Modified atmosphere packaging (MAP) used during export of mangoes creates a low oxygen environment that may reduce the efficacy of irradiation against B.dorsalis. 'Nam Dok Mai' mangoes infested with third instar larvae of B.dorsalis, wrapped with three different kinds (CF1, FF5, and H34M) of MAP bags or no MAP, were treated with gamma radiation at various doses ranging from 0 – 150 Gy. Non irradiation (0 Gy) or control groups were included for all MAP and no MAP treatments to provide natural response mortality rates. The use of MAP on infested mangoes increased mortality of B.dorsalis under irradiation treatment. The relative median potencies or ratios at LD50 of irradiation for no MAP compared to CF1, FF5, and H34M treatments were 1.40, 1.33, and 1.23, respectively. The average O2 and CO2 concentrations in MAP bags at 48 hrs after 60–Gy irradiation were 7.19% and 8.74% in the H34M bag, 8.60% and 21.21% in the CF1 bag, and 9.58% and 26.73% in the FF5 bag, respectively. A large scale confirmatory test of 35,000 B.dorsalis larvae at a radiation dose of 150 Gy in mangoes with H34M wrapping produced no survivors to the adult stage. Commercial use of MAP for mangos will not reduce the efficacy of the approved 150 Gy irradiation treatment for B.dorsalis.