Efficacy of dinotefuran (Alpine® spray and dust) on six species of stored product insects

•A combination treatment of dinotefuran combined with diatomaceous controls major stored product insect pests.•Efficacy of this dust formulation was not affected by relative humidity.•The dust was more effective than a spray formulation of dinotefuran alone.

Dinotefuran, an agonist of insect nicotinic acetylcholine receptors, was evaluated both as a 0.5% active ingredient aerosol spray and a dust combined with diatomaceous earth (DE), 5 g/m2 and 10 g/m2, at 45% r.h. and 75% r.h. Target species were six adult stored product insect species: Tribolium castaneum (Herbst), Rhyzopertha dominica (F.), Oryzaephilus surinamensis (L.), Tribolium confusum Jacqueline du Val, Dermestes maculatus (DeGeer), and Mezium affine Boieldieu. Adults were continually exposed for 4 d on the dusts, and assessments were done after 8 h and after 1, 2, 3, and 4 d to determine knockdown and adult survival/mortality. Mortality of T. castaneum, R. dominica, and O. surinamensis generally increased with exposure interval, and was 90% or more after three days of exposure at both dust rates and r.h. levels. Mortality of D. maculatus and T. confusum after three days ranged between 60 and 70% and 50 and 60%, respectively. Mortality of M. affine was 5% or less even after 4 days of exposure. Mortality of all species except M. affine was generally lower when exposed to the spray rather than the dust. No late stage larvae of T. castaneum, T. confusum, O. surinamensis, exposed to either the spray or the dusts emerged as adults, and only 3% of exposed D. maculatus emerged as adults. Results show that dinotefuran could be incorporated into management plans for control of stored product insects.