Spotted cutworm, Xestia c-nigrum (L.) (Lepidoptera: Noctuidae) responses to sex pheromone and blacklight

Abstract

Traps baited with the sex pheromone blend of (Z7)- and (Z5)-tetradecenyl acetate captured significant numbers of male spotted cutworm moths, Xestia c-nigrum (L.) compared to unbaited traps. Nearly no males were captured in traps baited with (Z7)-tetradecenyl acetate, the major pheromone component. Antennae of spotted cutworm males responded to (Z7)-, (E7)-, (Z5)- and (E5)-tetradecenyl acetate in the laboratory; however there was no response by moths in the field to the E isomers when presented in traps as major and minor components respectively of a binary blend or to the (E7) isomer as a single component. These findings clarify the makeup of a sex attractant that can be used for monitoring X. c-nigrum on agricultural crops in Washington. However, multi-year season-long monitoring of spotted cutworm moths in Yakima Valley apple orchards revealed differential responses to pheromone and blacklight traps. A spring flight period showed a strong moth response to the pheromone compared to blacklight, while a later summer flight period showed a weak moth response to the pheromone relative to blacklight. At this time, we do not know which trap type might best indicate spotted cutworm abundance and risk to crops. Published 2010.