Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 6, 2002
Publication Date: N/A
Interpretive Summary: Insect infestations in stored grain cost U.S. agriculture millions of dollars in damage due to contamination and loss of grain. The primary methods to monitor grain for insect infestation are both time-consuming and expensive. Availability of automated monitoring systems will allow off-site monitoring of stored grain, which will give the grain storage operators an important tool to aid in making pest management decisions. A prototype automated monitoring system, which uses an electronic grain probe trap, has been developed by scientists at the Center for Medical, Agricultural, and Veterinary Entomology and at the Subtropical Horticulture Research Station. Research was conducted to optimize this monitoring system by determining the relationship between number of openings in the body of the grain probe trap and capture of pests of stored grain. An improved electronic grain probe trap with 210 holes over a 40 cm long trapping surface was developed from this research. Subsequent tests found it to be equivalent but more cost-effective than the non-commercial prototype electronic probe traps previously tested. Availability of commercially available, automated grain monitoring system will facilitate technology transfer of this novel detection system for stored product pest management.
Technical Abstract: The relationship between number and arrangement of openings in the body of a grain probe trap and capture of pests of stored grain was determined in laboratory tests using adults of the rice weevil, Sitophilus oryzae (L.), the sawtoothed grain beetle, Oryzaephilus surinamensis (L.), and the red flour beetle, Tribolium castaneum (Herbst). Polyvinylchloride (PVC) probe bodies were attached to electronic sensor heads and capture of insects was recorded electronically using an Electronic Grain Probe Insect Counter (EGPIC) system. In comparisons among PVC probe trap bodies with 60 to 492 holes, tested at 71 insects per kg in 2.8 kg of soft wheat in cylindrical minisilos, capture of sawtoothed grain beetles and rice weevils was directly related with number of holes in the probe trap body, but there was no relationship for capture of red flour beetles. Subsequent tests were conducted comparing capture of sawtoothed grain beetles and rice weevils in a PVC probe body with 210 holes over a 40 cm long trapping surface with two commercially available probe traps, a polycarbonate probe trap with 180 holes over a 14 cm long trapping surface and a polyethylene probe trap with 750 holes over a 34 cm long trapping surface. The highest percent capture was in the polyethylene probe trap, but the 210 hole PVC probe body was as effective as the polycarbonate probe body for rice weevils and sawtoothed grain beetles at 71 and 17 insects per kg of wheat, respectively.