Communication is a way of conveying information by transmitting message from one person to another, and through it we interact. But for animals especially insects, their method of communication is very unique. They secrete a chemical called pheromone in communicating with their same species and surprisingly, knowing this method of communication has become of great advantage to scientist.
The word Pheromone referring to its etymology, comes from two Greek words “pherein” (to transfer or carry) and “hormon” (to excite). It is a chemical substance secreted by animals that affects the reproductive and social behavior of their same species.
There are many types of pheromones; one includes that of ants called trail pheromones that they use in trail-making. Social insects such as notorious killer bees secrete alarm pheromones when threatened by danger. Bees also secrete a recruitment pheromone called nasanov to maintain order in the colony and recruit members. And the type that sweet potato weevil use is the sex pheromone which they use for mating.
Sweet potato weevil is noted to be the most serious pest of sweet potato. It makes the crop bitter, drastically decreasing the yield and market value of the crop. Controlling this insect using conventional or traditional method is very difficult that other methods are looked into.
Knowledge about pheromone, that insects use as their common method of communication enabled scientists to develop a unique Integrated Pest Management for sweet potato weevil – using their own pheromone.
Dr. Erlinda Vasquez, a Professor of the Philippine Rootcrop Training Center (PhilRootCrops) of the Visayas State University and Dr. Dietmar Schimdt, a Chemist of the Institute of Chemistry at the University of Honhenheim, Stuttgart, Germany made use of the sex pheromone to control sweepotato weevil (SPW).
With the fund given to them by Alexander von Humboldht Foundation in Germany and assistance and facilities provided by other scientists and professors at University of Honhenheim, these two scientists were able to formulate a synthetic pheromone of a female sweet potato weevil identical to the naturally produced one.
Using the synthetic pheromone a test was conducted throughout selected areas in the Philippines (Baler,Central Luzon, Aurora, Leyte, Legaspi, and some parts in Mindanao). Pheromone traps were placed in the fields. It was observed replacing the natural sex pheromone emitted by female weevils, therefore, disrupting the communication between the male and female SPWs since males were more attracted to the synthetic pheromone than the natural one. With the effect of the synthetic pheromone to male weevils it was able to mass trap large number of them. The communication and mating disruption was found out reducing the weevil infestation to less than 10-15% from 30-60%.
Both scientists concluded that synthetic sweet potato weevil pheromone offers the most effective control method for SPW. It significantly reduced the weevil’s population density and infestation in the field. It is safe, efficient and simple, and compatible with other control measures for weevils. Aside from it, the new synthesis is relatively cheaper and affordable for farmers than the other suggested method.
The use of the pheromone as pest control is a good one. Weevils might be deceived, which is to their disadvantage, yet we had the advantage and that is- controlling them.