The pea weevil (
Bruchus pisorum
L.) (Coleoptera: Bruchidae) is one of the most damaging pests of pea (
Pisum sativum
L.) We investigated the role of pea volatiles on the electrophysiological and behavioral response of
B. pisorum using
electroantennography (EAG) and olfactometry bioassays. Plant volatiles emitted at different phenological stages were
collected
in situ by headspace on Porapak Q traps and analyzed through gas chromatography coupled to mass spectrometry
(GC-MS). Most abundant volatiles identified in all phenological stages were terpenes and green leaf volatiles. All tested
volatile extracts elicited significant EAG responses in both male and female
B. pisorum, with females exhibiting a greater
response (1.35 mV) than males (1.02 mV) to pea-pod volatiles. Volatiles from each phenological stage stimulated an
attractant behavioral response of both males and females
B. pisorum in olfactometer bioassay. A larger attraction of
B.
pisorum females was observed to volatiles from pods over other phenological stages (P < 0.001). These results suggest the
relative importance of volatiles cues from plant mediating host location by
B. pisorum. This work showed that plant volatiles
elicited electrophysiological and behavioral responses and that
B. pisorum female can discern between phenological stages
of
P. sativum based on those chemical cues.
