Pheromones
Pheromone technologies are a powerful, eco-friendly tool used in Integrated Pest Management (IPM) to monitor and control pest populations without relying heavily on chemical pesticides.
Source: Shutterstock
Introduction
Pheromones are natural chemical signals that insects use to communicate, especially for finding mates, and scientists have learned to replicate these signals and use them in agriculture and horticulture to manage pests in smart, targeted ways. In agricultural pest management, pheromone technologies have become an important component of Integrated Pest Management (IPM) strategies, and are used in several key ways, including:
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Monitoring: Pheromone traps attract specific insect species. Farmers can use these traps to track pest populations and decide if or when action is needed. Data collected can also support predictive modelling and pest forecasting.
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Mass Trapping: In some cases, large numbers of pheromone traps are deployed to reduce pest populations by trapping many individuals, especially males. This can be effective in managing pest outbreaks while avoiding chemical sprays.
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Mating Disruption: Synthetic pheromones are released into the air to confuse male insects, making it difficult for them to find females and reproduce. This interrupts the mating cycle, which can significantly lower the number of pests over time.
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Attract and kill: Pheromones are combined with an insecticide inside traps or bait stations. Pests are lured in by the scent, and are either killed upon contact or ingest a toxin. This method minimises chemical exposure to non-target organisms.
Using traps for FAW monitoring
Check out this learning video where experts talk about trapping and trap design for FAW monitoring.
This masterclass session involves two experts:
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The Use of Pheromones, Trap Design and Lures for FAW Control is presented by Dr Robert L. Meagher, Jr. USDA-ARS, Gainesville, Florida
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Research and Applied Pheromone Trapping for FAW in Vietnam is presented by Dr Tran Thi Thu Phoung from the Vietnam University of Agriculture
Video Presentation
Subscribe to ASEAN FAW Action Plan You Tube Channel
Sex pheromones
Sex pheromones are natural chemical signals that play a crucial role in insect mating and reproduction. Think of them as invisible messages — scents released into the air that help insects find and recognise potential mates of the same species.
These pheromones are especially powerful over long distances. For example, when a female moth releases sex pheromones, male moths can detect even tiny amounts in the air and begin flying toward the source. This behaviour, where an insect senses a chemical and moves in its direction, is called chemotaxis.
Once the male enters what's known as the "active space" — the zone where the pheromone scent is strong enough to detect — he can follow the scent trail to the female.
Understanding how these pheromones work has led to major advances in pest control, allowing scientists and farmers to disrupt insect mating patterns or monitor pest populations without using, or using less, harmful chemicals.
Structures of selected insect pheromones. Muscalure, the sex pheromone of the housefly, Musca domestica
Source: Ujváry, 2010
Pheromone technologies for FAW control have been discussed on several occasions in various Biocontrol Learning Series of the FAW Action Plan.
Check out these presentations to learn more about various solutions.
Video Presentation
Subscribe to ASEAN FAW Action Plan You Tube Channel
Research
Assessing the Effectiveness of Commercial Pheromones Available in Malaysia and Economic Evaluation of IPM Fall Armyworm (Abidin et al., 2023)
The Fall Armyworm (FAW) has become a major threat to corn production in Malaysia. To address this, the Malaysian Agricultural Research and Development Institute (MARDI) has been testing practical, cost-effective control solutions, including pheromones and pesticides, as part of an Integrated Pest Management (IPM) strategy for smallholder farmers.
Pheromone Trap Trials: Which Lure Works Best?
MARDI recently evaluated three commercially available FAW pheromone products:
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P061-90Lure from Costa Rica (ChemTica International)
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FAW Lure from India (Pest Control Pvt. Ltd.)
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Trece Pherocon® FAW from the United States (Trece Inc.)
Trece Pherocon® Fall Armyworm (Lure from USA)
Photo credit: Great Lakes IPM
All three lures performed equally well in laboratory tests; however, field trials showed the Costa Rican lure attracted 3.5 times more male moths than the other lures. Based on these findings, MARDI recommends utilizing the Costa Rican pheromone for monitoring and controlling fall armyworm (FAW) populations in corn fields.
Pesticide Options for FAW Control
In addition to pheromone trapping, MARDI has also introduced insecticides with the active ingredients:
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Chlorantraniliprole
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Emamectin benzoate
These are now part of MARDI’s recommended IPM toolkit to help farmers manage FAW more effectively.
Is IPM Worth It?: Costs and Benefits analysis
To understand whether IPM is practical for farmers, especially smallholders, MARDI conducted a partial budget analysis. The study evaluated both the costs and returns of using IPM in grain corn and sweet corn fields, with many farmers involved as direct experimenters applying MARDI’s Standard Operating Procedures (SOPs) on their plots.
Grain Corn: Strong Environmental Gains, Modest Financial Returns
Integrated Pest Management (IPM) showed significant environmental benefits in grain corn, such as a reduction in pesticide applications. However, financial advantages were limited, which makes it difficult for smallholder farmers to continue adopting IPM practices without economic incentives. To promote long-term adoption and protect environmental outcomes, government support in the form of subsidies, incentives, or regulations may be necessary.
Sweet Corn: A Win-Win Outcome
For sweet corn, the results were more promising:
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12% increase in yield
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Reduction in pesticide use from 18 sprays to just 5
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RM3,363.19 in financial gain per farmer
Sex Pheromones Study on the Cacao Pod Borer in Philippines
Field evaluation of the sex pheromone of the cacao pod borer (Conopomorpha cramerella Snellen) in the Philippines
To enhance Integrated Pest Management (IPM) strategies for controlling the Cacao Pod Borer (CPB), a field bioassaywas conducted in the southern Philippines. The study evaluated both a new synthetic sex pheromone blend and the optimal trap height for maximum effectiveness in cacao fields.
In the study, pheromone lures were placed at four different heights: 1.0 m above the canopy, 0.5 m above the canopy, at the canopy level (0.0 m), and 0.5 m below the canopy. A blank lure (control) was also positioned 1.0 m above the canopy. The main objective was to evaluate male CPB trap catches at these various heights.
The pheromone lures used were 100 µg doses in polyethylene vials (Just Plastic Ltd), containing a synthetic blend of:
A) Empty delta trap with sticky liner, (B) delta trap with a pheromone lure showing male CPB trap catch, and (C) delta trap placed 1.0 m above the tree canopy.
Source: Amalin et al., 2023
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(E,Z,Z)- and (E,E,Z)-4,6,10-hexadecatrienyl acetates
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Their corresponding alcohols
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Mixed in a 40:55:4:6 ratio
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Stabilized with 2,6-di-tert-butyl-4-methylphenol (BHT)
This blend was developed by the USDA-ARS Invasive Insect Biocontrol and Behavior Laboratory in Beltsville, MD, USA (Vanhove et al., 2015).
The Key Findings of the Study:
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Trap height matters: Traps placed 0.5 m or more above the canopy captured significantly more male CPB than lower placements.
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Pheromone blend is effective: The new pheromone blend significantly outperformed blank lures, validating its attractiveness in real-world field conditions.
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Optimal height confirmed: Follow-up trials across a 9-hectare cacao field reinforced that 0.5 m above canopy is the best trap placement for maximizing male moth captures.
The study confirms that this newly formulated CPB sex pheromone blend, when deployed 0.5 m above the canopy, is a valuable tool for monitoring and managing CPB populations.
Further Resources