Directional change in tunneling of subterranean termites (Isoptera: Rhinotermitidae) in response to decayed wood attractants.
Wood discs decayed with brown rot fungi and polymer discs impregnated with acetone extract of decayed wood were embedded in sand of a two-dimensional foraging arena to evaluate their attractant potential in directing termite tunnels toward them. Termites were released near one arena corner and were guided to follow the physical guideline of the arena edges. In the absence of the attractants, termites generally formed a relatively linear tunnel along the edges. When decayed wood discs or treated polymer discs were placed in wet sand near one side of the arena, termite tunnels departed from the arena edges and were oriented toward them. The attraction distance ranged from 12 to 18 cm. The attractant properties were most likely water soluble and permeated through wet sand to cause termites to change their orientation. The results demonstrated that when such attractants are placed near a bait station in the field, they may be used to direct termite foraging toward the station.
Trail-Following Behavior of Coptotermes formosanus and Reticulitermes flavipes (Isoptera: Rhinotermitidae)Is There a Species-Specific Response?
Abstract Bioassays were conducted to examine the response of Coptotermes formosanus Shiraki and Reticulitermes flavipes (Kollar) to whole body extracts of termites. Bioassays were also conducted to determine if trail-following behavior could be elicited in glass tubes after different lengths of exposure to termites and if termites showed any species-specific response to exposed tubes. Trail-following behavior was elicited in both species in response to whole body extracts of their nestmates. Although C. formosanus responded to the R. flavipes extract, R. flavipes did not show a difference in response to the C. formosanus extract versus solvent-treated controls. Trail-following behavior was elicited in both C. formosanus and R. flavipes by glass tubes exposed to termites for 5 min. Although neither species showed a preference for glass tubes exposed to their nestmates over tubes exposed to termites of the other species, there were differences in the persistency of trail-following substances deposited in tubes by the two species. When tubes were exposed to termites for 5 min, trail-following behavior was elicited by tubes exposed to C. formosanus for at least 1 h after exposure, whereas termites no longer responded to tubes that were exposed to R. flavipes 10–15 min after exposure. When tubes were exposed to termites for 14 d, termites deposited chemical markers which lasted for at least 8 d. There was no difference in the response of C. formosanus to tubes exposed to their nestmates versus tubes exposed to R. flavipes. However, R. flavipes showed a significant preference for tubes exposed to their nestmates over tubes exposed to C. formosanus. Because there was no evidence of a species-specific response by R. flavipes to tubes exposed to termites for only 5 min, it is possible that chemicals in the feces or in salivary secretions deposited in tubes influenced the behavior of R. flavipes in tests using tubes exposed to termites for 14 d.
Chemical Studies of Attractants Associated with Reticulitermes flavipes and R. virginicus
Both the eastern subterranean termite, Reticulitermes flavipes (Kollar), and R. virginicus (Banks) have an abdominal gland which secretes a compound inducing trail following and other attractant behavior in either species. Purification of the compound carried through 1 gas-liquid chromatographic run gave a product active at 0.1 ng. Western white pine rotted by the fungus Lenzites trabea Pers. ex Fr. produced trail following with material from 100 μg of wood per ml of test solution. On a weigh t basis, L. trabea-rotted wood is approximately 20 times as rich a source of attractant as the termites themselves. When the product from wood was gas chromatographed, the active region corresponded in retention time to that found for the gland substance.