Functional Characterization of a Fatty Acyl Reductase Identified from the Female Pheromone Gland of <i>Mythimna loreyi</i> (Lepidoptera: Noctuidae)

Sex pheromones, which play a critical role in mediating sexual communication of Lepidoptera, are biosynthesized by a variety of particular enzymes in specialized pheromone glands (PGs). Among these enzymes, fatty acyl-CoA reductases (FARs) catalyze the reduction of fatty acyl precursors to their corresponding alcohols. In this study, we identified 32 FARs from the genome of <i>Mythimna loreyi</i>, an important agricultural pest. Among all MlorFARs identified, only MlorFAR1 showed a PG expression pattern and exhibited a positive response to pheromone biosynthesis activating neuropeptide (PBAN) injection. Silencing MlorFAR1 reduced pheromone titers by 70.4-88.9% and significantly reduced mating rates at the 48-72 h postinjection time point. Heterologous expression in yeast confirmed that MlorFAR1 preferentially converted medium-chain fatty acid methyl esters to alcohols. These findings establish MlorFAR1 as a pivotal enzyme in the biosynthesis of sex pheromones in <i>M. loreyi</i>, providing a framework for the development of innovative pest management strategies.