Effectiveness of insecticide-incorporated bags to control stored-product beetles

Authors: KAVALLIERATOS, NICKOLAS - Agricultural University Of Athens; ATHANASSIOU, CHRISTOS - University Of Thessaly; Arthur, Franklin

Submitted to: Journal of Stored Products Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/4/2016
Publication Date: 12/1/2016
Publication URL: http://handle.nal.usda.gov/10113/5661763
Citation: Kavallieratos, N.G., Athanassiou, C.G., Arthur, F.H. 2016. Effectiveness of insecticide-incorporated bags to control stored-product beetles. Journal of Stored Products Research. 70:18-24. doi:10.1016/j.jspr.2016.11.001.

Interpretive Summary: Insect pest infestations can cause serious economic and quality losses in stored bagged grain and grain-based products, especially in developing countries in tropical regions. Vestergaard Inc. has manufactured storage bags that are impregnated with the insecticide deltamethrin. We conducted tests by exposing six species of adult stored product insects on the outside and inside of the fabric comprising these bags, to determine the time required to incapacitate the insects and also to see if the incapacitated insects would eventually die from the exposure. All species except one, the hide beetle, were incapacitated after one to three hours of exposure, but some species took longer to die than others. Also, depending on the species, incapacitation and death was slower on the inside compared to the outside fabric surface. The hide beetles were not incapacitated even after 5 days of exposure, and few died. Results show that grain managers can use these bags to protect their goods from most stored product beetle pests, but additional measures will be required to control adult hide beetles.

Technical Abstract: Adults of seven stored-product beetle species were exposed on the inside and outside surfaces of polypropylene polymer bags incorporated with the insecticide deltamethrin (approx. concentration of 3,000 ppm; ZeroFly® Storage Bags (3g/kg). Beetles were exposed for 60, 120, and 180 min, and 1, 3 and 5 days on the same treatment arenas, and after the 5 d interval the insects were removed and placed in untreated arenas for 5 more days. All Trogoderma variable (Ballion), the warehouse beetle, Prostephanus truncatus (Horn), Rhyzopertha dominica (F.), the lesser grain borer, and Tribolium castaneum (Herbst), the red flour beetle, were knocked down on the outside and inside surfaces of the bag after one hour of exposure. Mortality of T. variable, P. truncatus, and R. dominica increased during the exposure period, with generally lower mortality on the inside versus the outside of the bag after either 3 or 5 days of continual exposure. However, maximum mortality of T. castaneum, the red flour beetle, was only 5.6 ± 3.4% after 5 days of exposure. While it took longer for 100% knockdown of Sitophilus oryzae (L.), the rice weevil, compared to the above species, all S. oryzae were dead after 5 d of exposure on both surfaces. In contrast, after 5 days knockdown of S. zeamais (Motschlulsky), the maize weevil, did not exceed 30% and there was no mortality. After the Sitophilus species were transferred to untreated arenas, knockdown of all species decreased and mortality increased, indicating delayed mortality and no recovery from knockdown. Mortality of Dermestes maculatus (DeGeer), the hide beetle, did not exceed 5.6% at any time and there was no delayed mortality, indicating a potential tolerance of this particular strain of D. maculatus used in the study. Our results show that the ZeroFly® Storage Bags could effectively limit penetration of stored-product beetles through the bag into stored grains or milled grain products.