ECOLOGY, SAMPLING, AND MODELING OF INSECT PESTS OF STORED GRAIN, PROCESSING FACILITIES, AND WAREHOUSES
Location: Stored Product Insect Research Unit
Title: Comparison of Methods for Sampling Psocids in Stored Wheat
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: September 30, 2007
Publication Date: May 15, 2009
Citation: Throne, J.E., Opit, G.P., Flinn, P.W. 2009. Comparison of Methods for Sampling Psocids in Stored Wheat. In: S. Navarro, C.Adler, and L.S. Hansen (eds.), Proceedings of the International Organisation for Biological and Integrated Control, Paleartic Region Section Working Group on Integrated Protection of Stored Products, Poznan, Poland, August 20, 23, 2007. IOBC WPRS Bulletin 40: 67-74.
Psocids are an emerging problem in stored grain and in grain processing facilities in the United States. We compared several methods for sampling psocids in wheat stored in steel bins – grain trier samples, cardboard refuges on the surface of the grain and near the bin hatch, and automated sampling using the StorMax Insector system. The psocid species found were Liposcelis entomophila in 2005 and L. decolor in 2006. Numbers of psocids in cardboard refuges on the wheat surface were low immediately after bins were filled in July 2005, peaked in October, dropped to almost zero in December as temperatures decreased during winter, and then remained at low levels until the study was ended in April 2006. In 2006, the number of psocids in surface refuges increased gradually from August to mid-October, and remained at this level until the study was ended in early November. Number of psocids in cardboard refuges and in Insector probes was indicative of number of psocids in grain samples in both years. The results indicate that cardboard refuges or Insectors may provide an efficient method for sampling psocids in bins of wheat, and that psocid populations can increase quickly to high levels during storage even though they are low early in the storage period.