Horizontal transfer of methoprene in <i>Tribolium castaneum</i>

  • A. M. Tucker Kansas State University, Department of Entomology, 123 West Waters Hall, Manhattan, KS 66506 USA. Email address nos7147@ksu.edu
  • J. Campbell United States Department of Agriculture, Agricultural Research Service, Center for Grain and Animal Health Research, 1515 College Ave., Manhattan, KS 66502, USA.
  • F. H. Arthur United States Department of Agriculture, Agricultural Research Service, Center for Grain and Animal Health Research, 1515 College Ave., Manhattan, KS 66502, USA.
  • K. Y. Zhu Kansas State University, Department of Entomology, 123 West Waters Hall, Manhattan, KS 66506 USA. Email address nos7147@ksu.edu

Abstract

Aerosol applications of reduced risk insecticides such as pyrethrins, pyrethroids, and insect growth regulators are becoming more commonly used to manage stored-product insects in food facilities. However, these applications have a limited ability to penetrate into hidden refugia, where the majority of the pest population is located. Horizontal transfer of insecticides could occur as individuals directly treated or exposed to treated surfaces move into hidden refugia and encounter untreated individuals. In this series of studies, the potential for horizontal transfer of methoprene from treated Tribolium castaneum , the red flour beetle, to untreated individuals was evaluated. Adding larvae, pupae, or adults treated with methoprene to flour patches with untreated T. castaneum larvae, resulted in increased pupa and adult deformities and higher numbers of dead focal individuals, which suggests the potential for this mechanism. The transfer mechanism might be flour substrate contamination, transfer during contact of individuals, and/or cannibalism of individuals exposed to insecticides. Experiments focused on isolating the impact of contact and cannibalism on horizontal transfer did not detect a significant increase in mortality. Experiments focused on flour substrate contamination resulted in decreased adult emergence as well as lower survival, and higher rates of deformities. These findings suggest that substrate contamination is the more likely mechanism for horizontal transfer, and although horizontal transfer can occur, the impact of this process on populations needs further evaluation.

Keywords: Red flour beetle, Tribolium castaneum, Methoprene, Horizontal transfer


Veröffentlicht
2010-09-20
Rubrik
Section: Residual Insecticides - Synthetic and Botanical