Nonanal, a new fall armyworm sex pheromone component, significantly increases the efficacy of pheromone lures.

Abstract

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is a global pest that feeds on more than 350 plant species and severely limits production of cultivated grasses, vegetable crops and cotton. An efficient way to detect new invasions at early stages and monitor and quantify the status of established infestations of this pest is to deploy traps baited with species-specific synthetic sex pheromone lures. We reexamined the compounds in the sex pheromone glands of FAW females by GC-EAD, GC-MS, behavioral, and field assays. A new bioactive compound from pheromone gland extracts was detected in low amounts (1% relative to (Z)-9-tetradecenyl acetate (Z9-14:OAc), the main pheromone component) and identified as nonanal. This aldehyde significantly increased attraction of male moths to a mix of Z9-14:OAc and (Z)-7-dodecenyl acetate in olfactometer assays. Adding nonanal to this 2-component mix also doubled male trap catches relative to the 2-component mix alone in cotton fields, whereas nonanal alone did not attract any moths. The addition of nonanal to each of three commercial pheromone lures also increased male catches by 53-135% in sorghum and cotton fields. The addition of nonanal to pheromone lures should improve surveillance, monitoring and control of FAW populations. This article is protected by copyright. All rights reserved.