Development of a pheromone monitoring system for the goosefoot groundling moth, Scrobipalpa atriplicella (von Röslerstamm) in quinoa, Chenopodium quinoa (Willdenow)

The goosefoot groundling moth, Scrobipalpa atriplicella, (Lepidoptera: Gelechiidae) is a serious pest of quinoa, Chenopodium quinoa, in North America and Europe. Previous studies found male S. atriplicella were attracted to a generic pheromone lure containing (Z)-5-dodecenyl acetate. Here, we identified further candidate sex pheromone components from female pheromone glands using gas chromatography-electroantennographic detection. We confirmed (Z)-5-dodecenyl acetate to be an antennally active compound, and identified a previously unidentified minor component, (E)-5-dodecenyl acetate. Field tests confirmed males were most attracted to a two-component blend in a 95:5 ratio of (Z)-5-dodecenyl acetate to (E)-5-dodecenyl acetate. We found that the 95:5 major to minor ratio captured more S. atriplicella moths and the lowest number of non-target noctuid moths compared to other ratios tested. The number of S. atriplicella captured varied with trap type, but not the two heights tested (0.5 and 1 m), however, we recommend pheromone-baited wing traps deployed at either at 0.5 or 1 m heights to reduce the possibility of trap saturation with sticky traps with smaller surface areas. These findings allow for future development of a pheromone-based monitoring program for this significant pest of quinoa in Canada.