A very special attraction: pheromone traps
Technical note on a very special attraction: pheromone traps, with a focus on diagnosis, prevention and criteria applicable to professional pest management.
We normally refer to “pheromone traps” when in reality these traps usually have controlled release devices as attractants that precisely and regularly emit semiochemicals, which may or may not include pheromones.
Semiochemicals are volatile chemical compounds that act as intermediaries in interactions between organisms, thus triggering behavioral or physiological responses. In other words, it is the way that many insects communicate. This communication often plays a key role in ensuring the life cycle of the insect is fulfilled.
Semiochemicals, in turn, can be classified into two large groups: allelochemicals and pheromones. This grouping depends on whether the interactions are interspecific or intraspecific, respectively.
So, when we refer to allelochemicals we are talking about substances that communicate to individuals of a species different from the species that emits them. Allelochemicals are subdivided into several groups depending on how they influence this communication between the sender and the receiver. If it is favorable to the receiver but not to the sender, we will call them kairomones; If the individual's response is adaptively favorable to the sender but not to the receiver, they are called allomonas; and finally, if it is favorable for both the sender and the receiver, they will be called synomones.
As for pheromones, from the Greek phereum, carry, and horman, excite or stimulate, are substances released by one member of a species to cause a specific response in another member of the same species.
Pheromones can be further classified based on the action mediated, such as an alarm pheromone, congregating or grouping, sexual, etc.
Whether allelochemicals or pheromones, it is sometimes useful to refer to them as copulation interrupters, attractants, repellents, deterrents, stimulants, or other descriptive terms to simplify their identification.
Why use them?
Sex pheromones and kairomones are of particular interest to those who practice Integrated Pest Management. These compounds can be used in different applications: monitoring population levels, delimitation of infested areas, identification of areas to be treated with insecticides, monitoring the progress of control operations, control by the method of sexual confusion or interruption of copulation, trapping and control of insects by mass capture in different types of traps.
They have numerous advantages that we can exploit. They are not environmental contaminants, they reduce the pest population for long periods, they are easily used and manipulated for IPM whose bases are ecological, they have a low risk in handling the product and have high specificity, which provides precision in its application in monitoring and control.
They are ideal for use in sensitive areas where there are restrictions on the use of certain insecticides. Furthermore, there are no current records that indicate resistance phenomena as occurs with the frequent use of chemical pesticides.