CHEMICAL SIGNALS FOR MANAGING INSECTSTitle: ANTENNAL AND BEHAVIORAL RESPONSES OF LYGUS LINEOLARIS (PALISOT DE BEAUVOIS) (HETEROPTERA: MIRIDAE) TO METATHORACIC SCENT GLAND COMPOUNDS
Submitted to: Journal of Entomological Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 7, 2006
Publication Date: N/A
Interpretive Summary: The tarnished plant bug (TPB) is a major pest of a multitude of crops. Nowadays, the TPB is especially a problem in cotton because it is able to attack the new modified strains of cotton (over 90% of the U.S. acreage). TPBs use chemical odors to find one another for reproduction, so methods that interfere with their chemical communication could be useful in suppressing the damage they cause. The female bugs produce chemicals to attract a mate, but all efforts to identify the attractant have failed. However, we have found that certain simple chemicals released by adult TPBs counteract the attraction of males to females by inducing females to stop producing their attractant and/or interfering with the perception of the attractant by males. This information should be of interest to scientists conducting research on these kinds of difficult to control insects, and could eventually provide growers an alternative to pesticides for managing this and other kinds of plant bugs.
Hexyl and (E)-2-hexenyl butyrates and (E)-4-oxo-2-hexenal are major components of the metathoracic scent gland (MSG) secretion and aeration samples of many plant bugs (Miridae), including the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois). Laboratory and field experiments were performed 1) to determine the extent to which MSG-produced compounds are detected by antennae of Lygus lineolaris males and females and, 2) to elucidate the behavioral activity associated with the antennally active MSG compounds. The three major MSG-produced compounds elicited strong antennal responses by both sexes of L. lineolaris. In Y-track olfactometer tests, attraction of L. lineolaris males to virgin females was significantly reduced when a dispenser loaded with hexyl butyrate was placed with the virgin females. Hexyl butyrate tested alone against a blank control significantly repelled males. In the field, ternary and partial binary combinations of these three EAD-active compounds failed to attract either sex of L. lineolaris, while virgin females attracted a significant number of males. However, addition of hexyl butyrate and/or (E)-2-hexenyl butyrate to virgin female-baited traps significantly reduced the number of L. lineolaris males caught to the level of the blank control traps. This might be due to either a negative effect on pheromone release by the females or direct repellency of males or both. These MSG compounds may be useful for mating disruption and other pest management tactics against economically important plant bugs.