Submitted to: Pest Management Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/14/2010
Publication Date: 3/21/2011
Publication URL: http://hdl.handle.net/10113/48983
Citation: Athanassiou, C.G., Arthur, F.H., Throne, J.E. 2011. Efficacy of layer treatment with methoprene for control of Rhyzopertha dominica (Coleoptera: Bostrychidae) on wheat, rice, and maize. Pest Management Science. 67(4):380-384. doi: http://dx.doi.org/10.1022/ps.2064. Interpretive Summary: Lesser grain borers are serious pests of stored grains throughout the world, but they have developed resistance to many of the insecticides used for their control. Thus, alternative control technologies are required. Insect growth regulators are a type of insecticide that interfere with insect development, but they have low mammalian toxicity. We evaluated the effectiveness of the insect growth regulator methoprene for control of lesser grain borers in wheat, rice, and corn to determine whether treating just a layer on the top of the grain mass, rather than the whole grain mass, would provide effective control. In wheat and rice, the layer treatments were not as effective as whole-grain treatment, but there were fewer progeny produced as the application rate of methoprene increased. However, on corn the partial treatments were as effective as the whole-grain treatment. Our results suggest that partial layer treatments with methoprene can be used to control lesser grain borers on corn, but may not be effective for control of this species on wheat and rice.
Technical Abstract: Insect growth regulators are promising alternatives to traditional pesticides in stored grain. The efficacy of the juvenile hormone analogue methoprene was evaluated as a layer treatment in a laboratory experiment for control of Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) in wheat, rice and maize. Adults of R. dominica were placed in vials containing 33, 26, and 29 g (to a depth of 6.5 cm) of wheat, rice, and maize, respectively, that was entirely or partially treated with 1, 5, or 10 ppm methoprene. In wheat and rice, the layer treatments were not as effective as the whole-grain treatment, but there was decreased progeny production as the application rate increased. However, on maize the partial treatments were as effective as the whole-grain treatment at 5 and 10 ppm. Our results suggest that partial layer treatments with methoprene can be used to control R. dominica on maize but may not be effective for control of this species on wheat and rice.