Defining defensive secretions of brown marmorated stink bug, Halyomorpha halys

Brown marmorated stink bug (BMSB) (Halyomorpha halys (Stål)) is an invasive pest of East-Asian origin. It is currently detected in 42 states in the United States, parts of Canada and Europe. BMSB establishment has resulted in major economic impacts on a number of agricultural industries.

BMSB release defensive volatiles and other secretions when stressed. The components of the secretions play an important role in ecological interactions and can also cause contamination of agricultural products. 

With growing population of BMSB in the field, there is a need to characterize their defensive secretions. The goal of this research was to identify the components of the defensive secretions produced by the five stages of nymphs and adult BMSB. HS-SPME-GCMS was used to identify secretion volatile compounds. BMSB were gathered from the Willamette Valley, Oregon. Bugs were stressed prior to their placement in headspace vials for GCMS analysis.

The adult defensive secretion was primarily comprised of: tridecane, dimethyl disulfide, acetoin, trans-2-decenal, and 2,3-butanediol. An increase in their concentration was observed with BMSB development. Tridecane, a primary component of adult secretion doubled in its level from Nymph 1 to adult. Dimethyl disulfide and Octanoic acid were found to be major component in third and first instars respectively. Components of BMSB secretions can be categorized as 1) aroma compounds and 2) ecologically important compounds such as Octanoic acid. Other compounds may also play a role in both of these compound categories.