This study evaluates gas chromatography (GC) as a potential
technology for improved detection of hidden insect infestation. It
is well documented in the literature that insect herbivory can elicit
changes in host plant chemistry and volatile emissions (reviewed
in Karban and Baldwin, 1997; Howe and Jander, 2008). It also has
been shown that chemical changes can occur within host fruit as a
result of insect infestation (Boevé et al., 1996; Hern and Dorn, 2001;
Carrasco et al., 2005). In this study we examined citrus infested
with A. suspensa to determine if infested fruit emitted a detectable
chemical profile distinct from that of non-infested citrus. Samples
of headspace volatiles were collected at various stages of infestation
and chemical analysis was performed with several types of
GC equipment. Since the primary goal was development of a rapid
screening protocol for “signature chemicals”, the majority of analyses
were performed with a rapid (9 min) GC separation method. To
evaluate the efficacy of separation with this rapid method, and to
identify the volatile chemical components, a slower (25 min), high
resolution GC separation was performed in combination with mass
spectral analysis. In addition, we conducted a preliminary evaluation
of a portable ultra-high speed GC analyzer for detection of
these same chemicals using a method requiring less than 80 s for
sampling and chemical analysis.