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ARS Home » Pacific West Area » Hilo, Hawaii » Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center » Tropical Crop and Commodity Protection Research » Research » Publications at this Location » Publication #310473

Title: Phytosanitary irradiation for fresh horticultural commodities: generic treatments, current issues, and next steps

Author
item Follett, Peter

Submitted to: Stewart Postharvest Review
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/11/2014
Publication Date: 12/10/2014
Citation: Follett, P.A. 2014. Phytosanitary irradiation for fresh horticultural commodities: generic treatments, current issues, and next steps. Stewart Postharvest Review. 10(3):1-7.

Interpretive Summary: Phytosanitary treatments such as irradiation disinfest host commodities of quarantine insect pests before they are exported to areas where the pests do not occur, and are often the simplest approach to overcome regulatory trade barriers and gain market access. Generic radiation doses of 150 Gy for quarantine treatment of tephritid fruit flies, and 400 Gy for other insects except pupae and adult Lepidoptera (moths and butterflies) are approved and in use. The availability of generic radiation treatments has resulted in a steady increase in the international use of phytosanitary irradiation for trade in tropical fruits and vegetables. Current research is focused on development of specific doses for quarantine Lepidoptera not covered by the generic treatments; reduction of dose levels for specific pests and commodities to shorten treatment time; development of generic doses below 400 Gy for economically important groups of quarantine arthropods other than fruit flies; and development of information on commodity tolerance and novel methods to reduce injury and extend shelf-life. Several issues present barriers to the wider use of phytosanitary irradiation including the 1 kGy limit, labeling requirement, restrictions on the use of modified atmosphere, and the limited number of country approvals for the use of phytosanitary irradiation. These issues must be addressed to facilitate expansion. The development of small-scale cabinet style x-ray machines could provide farmers and packinghouses with in-house treatment capability, and accelerate adoption of the technology.

Technical Abstract: Phytosanitary treatments such as irradiation disinfest host commodities of quarantine insect pests before they are exported to areas where the pests do not occur, and are often the simplest approach to overcome regulatory trade barriers and gain market access. The United States, Australia and the International Plant Protection Convention have approved the generic radiation dose of 150 Gy for quarantine treatment of tephritid fruit flies, and the U.S. has approved the generic dose of 400 Gy for other insects except pupae and adult Lepidoptera (moths and butterflies). The availability of generic radiation treatments has resulted in a steady increase in the international use of phytosanitary irradiation for trade in tropical fruits and vegetables. Recent developments in phytosanitary irradiation are discussed. Current research is focused on development of specific doses for quarantine Lepidoptera not covered by the generic treatments; reduction of dose levels for specific pests and commodities to shorten treatment time; development of generic doses below 400 Gy for economically important groups of quarantine arthropods other than fruit flies; and development of information on commodity tolerance and novel methods to reduce injury and extend shelf-life. Several issues present barriers to the wider use of phytosanitary irradiation including the 1 kGy limit, labeling requirement, restrictions on the use of modified atmosphere, and the limited number of country approvals for the use of phytosanitary irradiation. These issues must be addressed to facilitate expansion. The development of small-scale cabinet style x-ray machines could provide farmers and packinghouses with in-house treatment capability, and accelerate adoption of the technology.