Submitted to: USDA Miscellaneous Publication 1343
Publication Type: Abstract Only
Publication Acceptance Date: 2/11/2000
Publication Date: N/A
Technical Abstract: Logs infested with Asian longhorned beetles (ALB) from sites in Chicago, Illinois, were transported to the APHIS quarantine facility in Otis, MA. Aeration extracts were prepared by confining groups of 5-10 male or female adults that emerged from these logs in the spring of 1999 in 1 L glass chambers (sometimes with twigs of Norway maple, Acer platonoides), and drawing air over the beetles by vacuum (ca 1 L/min) through an absorbent polymer (Super Q, Altech Associates, Inc., 200mg). The volatile natural products were eluted with methylene chloride, and the extracts were analyzed by the gas chromatography-electroantennographic detector technique (GC-EAD) and GC-mass spectrometry (GC-MS) in the electron impact and chemical ionization modes. Males produced two compounds not detected from females, and antennae from ALB males and females were especially sensitive to these male-specific compounds. The electrophysiologically active male specific compounds were identified by their MS, followed by synthesis of standards verifying the structures as dialkyl ethers of a type heretofore unknown from insects: 4-(n-heptyloxy)butanal and 4-(n-heptyloxy)-1-butanol. In preliminary tests in the quarantine laboratory these compounds appeared to stimulate flight and walking in both sexes. However, July 1999 field tests in China failed to demonstrate attraction to these compounds, with or without a mixture of six host volatiles. Laboratory and field observations indicate that ALB males are territorial and that males recognize females upon antennal contact. Further testing is needed to determine the behavioral role of the male-specific volatiles and the chemical identity of the female contact recognition pheromone.