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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 #329021
Research Project: Detection, Control and Area-wide Management of Fruit Flies and Other Quarantine Pests of Tropical/Subtropical Crops

Location: Tropical Crop and Commodity Protection Research

Title: Effect of irradiation on queen survivorship and reproduction in the invasive fire ant Solenopsis invicta,(Hymenoptera: Formicidae) and a generic phytosanitary irradiation treatment for ants

Author
item Follett, Peter
item PORCEL, SOL - Consejo Nacional De Investigaciones Científicas Y Técnicas(CONICET)
item CALCATERA, LUIS - Consejo Nacional De Investigaciones Científicas Y Técnicas(CONICET)

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/26/2016
Publication Date: 12/4/2016
Citation: Follett, P.A., Porcel, S., Calcatera, L. 2016. Effect of irradiation on queen survivorship and reproduction in the invasive fire ant Solenopsis invicta,(Hymenoptera: Formicidae) and a generic phytosanitary irradiation treatment for ants. Journal of Economic Entomology. 109(6):2348-2354.

Interpretive Summary: Ants are common hitchhiker pests on traded agricultural commodities that could be controlled by postharvest irradiation treatment. We studied radiation tolerance in queens of the red imported fire ant Solenopsis invicta Buren to determine the dose sufficient for its control. Irradiation strongly reduced fecundity and longevity in S.invicta queens. Results with S.invicta and three other invasive ants studied previously, Wasmannia auropunctata(Roger), Pheidole megacephala(F.), and Linephithema humile(Mayr), suggest a minimum absorbed dose of 125Gy should be sufficient as a generic quarantine treatment to prevent reproduction in ants.

Technical Abstract: Ants are common hitchhiker pests on traded agricultural commodities that could be controlled by postharvest irradiation treatment. We studied radiation tolerance in queens of the red imported fire ant Solenopsis invicta Buren to determine the dose sufficient for its control. Virgin or fertile queens were collected from Santa Fe and Formosa provinces in Argentina and reared in the laboratory in microcolonies. Virgin queens were irradiated at 0 (control), 60, 90, 120, or 150Gy, and fertile queens were irradiated at 0, 60, 125, and 190Gy, and then followed for 11-wk in the microcolonies to evaluate survival and reproduction. Virgin queens lay trophic eggs that do not hatch, whereas fertile queens lay eggs that hatch and develop into brood. In general, queen oviposition and survival decreased with increasing irradiation dose. For virgin queens, no eggs were laid by irradiated queens after the third week, whereas the control queens continued laying eggs throughout the 11-week experiment. For fertile queens, only one larva was observed in the 60Gy treatment and no larvae were observed in the 125 and 190Gy treatments, whereas a total of 431 larvae and 83 pupae were produced by untreated control queens during 11 weeks. Survivorship of virgin and fertile queens was similarly reduced by irradiation treatment. Irradiation strongly lowered fecundity and shortened longevity in S.invicta queens as was observed previously in three other invasive ants, Wasmannia auropunctata(Roger), Pheidole megacephala(F.), and Linephithema humile(Mayr). A minimum absorbed dose of 125Gy should be sufficient as a generic quarantine treatment to prevent reproduction in ants.