Quantitative analysis of gas chromatography-coupled electroantennographic detection (GC-EAD) of plant volatiles by insects

PremisePlant-interacting insects receive plant volatile signals through their antennae, and voltage changes across an antenna exposed to volatile stimuli can be measured to determine if insects can perceive them, often by coupling gas chromatography to electroantennographic detection (GC-EAD). Current methods for analysing GC-EAD data rely on qualitative observation, rather than using quantitative analysis, and are thus prone to bias. Methods and ResultsWe developed a novel quantitative methodology for analysis of GC-EAD data using a signal processing technique on EAD data to compare responses of hawkmoths and bumble bees to a library of common floral volatiles. Responses varied between species and sexes and these responses were in some cases affected by compound type or modification. Our method also works with existing, published GC-EAD datasets. ConclusionsOur novel GC-EAD analysis technique is robust to baseline drift and low signal:noise ratios commonly found in GC-EAD data, and provides a way forward for quantitative studies of plant volatile- mediated plant-insect interactions.