From Factory to Field: Sex Pheromone of Plutella xylostella Produced in Yeast Cell-Factories Validated in Laboratory and Field Trials

<i>Plutella xylostella</i> (L.) (Lepidoptera: Plutellidae), the diamondback moth (DBM), is a cosmopolitan pest of brassicas. To validate and compare the performance of yeast-derived sex pheromone components with chemically synthesized ones, we studied the behavioral and electrophysiological responses (EAGs) of male DBM adults. In addition, using gas chromatography coupled with electroantennographic detection (GC-EAD), we examined whether any residual impurities present in yeast-derived pheromone components can be perceived by the insects' antennae and are thus capable of interfering with normal behavior. Furthermore, we assessed the performance of the yeast-derived pheromones under field conditions through monitoring trials conducted in cabbage crops in Greece. Electrophysiological and behavioral assays revealed equivalent responses from the insects to both the yeast-derived (BIO) and chemically synthesized (CHEM) pheromone blends. Consistent with this, GC-EAD results showed no significant differences in antennal response to minor impurities present in the BIO blend compared to the CHEM blend. Finally, it was demonstrated that the binary pheromone blend-comprising (<i>Z</i>)-11-hexadecenal and (<i>Z</i>)-11-hexadecenyl acetate derived from (<i>Z</i>)-11-hexadecen-1-ol produced by yeast cell-factories-was as efficient and specific for trapping male moths in cabbage fields as the conventional ternary synthetic blend [(<i>Z</i>)-11-hexadecenal and (<i>Z</i>)-11-hexadecenyl acetate and (<i>Z</i>)-11-hexadecen-1-ol]. The yeast-derived mixture contained small amounts of unoxidized (<i>Z</i>)-11-hexadecen-1-ol due to incomplete oxidation.