Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 6, 2000
Publication Date: N/A
Interpretive Summary: The Formosan subterranean termite (Coptotermes formosanus Shiraki) is the most destructive termite where it occurs. Chemical control strategies have failed to protect structures from this termite, resulting in many millions of dollars of structural damage. Bacteria, which are lethal to Formosan subterranean termites, have been isolated from termite colonies and evaluated for their ability to kill this termite. Several strains of bacteria killed 100% of the termites in laboratory tests. Subterranean termites cost Americans more than a billion dollars a year over most of the continental United States and Hawaii. The isolation and identification of bacteria that will weaken or kill termites can potentially solve termite problems in an environmentally friendly manner helping to reduce the use of synthetic chemical.
Technical Abstract: Examination of Formosan subterranean termites, Coptotermes formosanus Shiraki, for possible biological control agents revealed the presence of 15 bacteria and 1 fungus associated with dead termites from New Orleans, Louisiana, USA. All of the species were gram-negative bacteria. Bacterial isolated from dead termites were primarily Serratia marcescens Bizio which caused septicemia in C. formosanus and also appeared to contain proteolytic enzymes. Multiple strains of S. marcescens were isolated. Six of the 8 strains of S. marcescens were red in color, probably not pathogenic in humans and candidates as biological control agents for C. formosanus. Bacteria isolated from termite substrate included Corynebacterium urealyticum, Acinetobacter calcoacet/baumannii/Gen2, S. marcescens, and Enterobacter gergoviae. Some of these bacteria are potential human pathogens and may have public health implications for people with infested residences, pest control professionals, contractors, and termitologists. Forced exposure bioassays demonstrated that the T8 strain of S. marcescens killed 100% of C. formosanus by day 19.