Submitted to: Biocontrol Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/8/2002
Publication Date: 6/1/2003
Citation: DOWD, P.F., VEGA, F.E. AUTODISSEMINATION OF BEAUVERIA BASSIANA BY SAP BEETLES (COLEOPTERA: NITIDULIDAE) TO OVERWINTERING SITES. BIOCONTROL SCIENCE AND TECHNOLOGY. 2003. v. 13. p. 69-79. Interpretive Summary: Sap beetles damage a variety of fruits, vegetables, and grains, and also carry many plant diseases, some of which produce toxins harmful to animals and people. The ability of sap beetles to hide within fruits, vegetables, and corn ears makes them difficult to manage by conventional means, such as use of insecticides. A modified sap beetle trap was used to contaminate these insects in the fall with an insect disease. The strain of disease used was recovered from sites where sap beetles overwintered in groups, but very few non-target insects were found in these sites. This selective, nonchemical management strategy may also be useful for other insect pests that overwinter in groups, ultimately resulting in better quality, lower-priced fruits, vegetables, and grains that may also have reduced levels of mold toxins.
Technical Abstract: An autoinoculative device was used to test the ability of sap beetles (Coleoptera: Nitidulidae) to carry a specific strain of Beauveria bassiana (Balsamo) Vuillemin to overwintering sites in a multi-year field study. The device was baited with the pheromone and coattractants for the dusky sap beetle (Carpophilus lugubris Murray) and placed in the field in the fall of each year. The introduced strain occurred at high frequency from the B. bassiana isolated in the fall of all years tested. The introduced strain of B. bassiana was often isolated at high frequency from all the B. bassiana infected sap beetles recovered from the overwintering traps, although in some years, very few isolates were found. The introduced strain was primarily isolated from C. lugubris and C. antiquus, but species distribution was also dependent on the overwintering trap design used. Few non-sap beetles species of insects were recovered from the artificial overwintering sites. Although B. bassiana was isolated from free flying sap beetles caught in traps in the spring of each year, none were infected with the introduced strain. The autoinoculating device provides selective contamination of sap beetles in overwintering sites when used in the fall. It may be useful in providing some control of sap beetles or other insects where limited numbers of mass overwintering sites (such as tree holes) occur.