Susceptibility to sulfuryl fluoride and lack of cross-resistance to phosphine in developmental stages of the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae).
BACKGROUND
Our aim was to ascertain the potential of sulfuryl fluoride (SF) as an alternative fumigant to manage phosphine-resistant pests. We tested the susceptibility of all life stages of red flour beetle, Tribolium castaneum (Herbst), to SF and assessed the presence of cross-resistance to this fumigant in phosphine-resistant strains of this species.


RESULTS
Analysis of dose-response data indicated that the egg was the stage most tolerant to SF under a 48 h exposure period. At LC50 , eggs were 29 times more tolerant than other immature stages and adults, and required a relatively high concentration of 48.2 mg L(-1) for complete mortality. No significant differences in tolerance to SF were observed among the three larval instars, pupae and adults, and all of these stages were controlled at a low concentration of 1.32 mg L(-1) . Phosphine-resistant strains did not show cross-resistance to SF.


CONCLUSIONS
Our research concluded that the current maximum registered rate of SF, 1500 gh m(-3) , is adequate to control all the post-embryonic life stages of T. castaneum over a 48 h fumigation period, but it will fail to achieve complete mortality of eggs, indicating the risk of some survival of eggs under this short exposure period. As there is no cross-resistance to SF in phosphine-resistant insects, it will play a key role in managing phosphine resistance in stored-grain insect pests.
Department of Agriculture, Fisheries and Forestry, Brisbane, Qld, Australia.|Plant Biosecurity Cooperative Research Centre, Bruce, ACT, Australia.
Rajeswaran
R
Jagadeesan
Department of Agriculture, Fisheries and Forestry, Brisbane, Qld, Australia.|Plant Biosecurity Cooperative Research Centre, Bruce, ACT, Australia.
Manoj K
MK
Nayak
Department of Agriculture, Fisheries and Forestry, Brisbane, Qld, Australia.|Plant Biosecurity Cooperative Research Centre, Bruce, ACT, Australia.
Hervoika
H
Pavic
Department of Agriculture, Fisheries and Forestry, Brisbane, Qld, Australia.
Kerri
K
Chandra
Department of Agriculture, Fisheries and Forestry, Brisbane, Qld, Australia.|Plant Biosecurity Cooperative Research Centre, Bruce, ACT, Australia.
Patrick J
PJ
Collins
D000818:Animals; D005260:Female; D007300:Insect Control; D007305:Insecticide Resistance; D007306:Insecticides / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D008297:Male; D010720:Phosphines / Q000494:pharmacology*; D011679:Pupa / Q000187:drug effects / Q000254:growth & development; D013441:Sulfinic Acids / Q000494:pharmacology*; D014231:Tribolium / Q000187:drug effects* / Q000254:growth & development*
D007306:Insecticides; D010720:Phosphines; D013441:Sulfinic Acids; C048899:sulfuryl fluoride; C044646:phosphine
alternative fumigants; cross-resistance; eggs; phosphine; stored-grain pests