T J Welsh1,2, L D Stringer1,2,3, R Caldwell4, J E Carpenter4, D M Suckling1,2,3. 1. a Biosecuity Group, The New Zealand Institute for Plant and Food Research Limited , Christchurch , New Zealand. 2. b Better Border Biosecurity , Christchurch , New Zealand. 3. c School of Biological Sciences , University of Auckland , Christchurch , New Zealand. 4. d United States Department of Agriculture - Agricultural Research Service , Tifton , GA , USA.
Abstract
PURPOSE: Brown marmorated stink bugs, Halyomorpha halys Stål (Hemiptera: Pentatomidae), are regularly intercepted, but there are few eradication tools. Currently, no sterile insect technique program exists for Hemiptera. MATERIALS AND METHODS: Adult males were irradiated at 4-60 Gy, mated and their progeny reared for two generations, with mortality assessed at F1 egg, F1 adult and F2 egg stages. RESULTS: The F1 eggs showed a dose response to irradiation between 4 and 36 Gy, with 97% sterility at 16 Gy, and higher doses producing complete egg mortality. Only rare F1 survivors had progeny, but the F2 generation showed identical responses between maternal and paternal lines; most egg batches showed either very low or very high mortality. Irradiation with 16 Gy resulted in 98.5% sterility, cumulative over F1 and F2. CONCLUSIONS: Lack of a dose response at the F2 generation precludes the use of irradiation-induced inherited sterility. The conventional sterile insect technique appears possible by irradiation of males from ∼12 to 16 Gy. The effect of radiation dose on females is not known, thus we cannot conclude whether bi-sex release is feasible so for now the release of males only is recommended. More work is needed on the competitive fitness of irradiated males, and logistics such as mass rearing or field collection, in order to determine the feasibility of the approach.
PURPOSE:Brown marmorated stink bugs, Halyomorpha halys Stål (Hemiptera: Pentatomidae), are regularly intercepted, but there are few eradication tools. Currently, no sterile insect technique program exists for Hemiptera. MATERIALS AND METHODS: Adult males were irradiated at 4-60 Gy, mated and their progeny reared for two generations, with mortality assessed at F1 egg, F1 adult and F2 egg stages. RESULTS: The F1 eggs showed a dose response to irradiation between 4 and 36 Gy, with 97% sterility at 16 Gy, and higher doses producing complete egg mortality. Only rare F1 survivors had progeny, but the F2 generation showed identical responses between maternal and paternal lines; most egg batches showed either very low or very high mortality. Irradiation with 16 Gy resulted in 98.5% sterility, cumulative over F1 and F2. CONCLUSIONS: Lack of a dose response at the F2 generation precludes the use of irradiation-induced inherited sterility. The conventional sterile insect technique appears possible by irradiation of males from ∼12 to 16 Gy. The effect of radiation dose on females is not known, thus we cannot conclude whether bi-sex release is feasible so for now the release of males only is recommended. More work is needed on the competitive fitness of irradiated males, and logistics such as mass rearing or field collection, in order to determine the feasibility of the approach.