No More Worries About Stinky Sweet Potatoes: Sex Pheromone Traps Catch Sweet Potato Weevils Without Pesticide Spraying

Every summer, sweet potato farmers suffer damage from the sweet potato weevil (Cylas formicarius), commonly known as "stinky sweet potato." "Sweet potato weevils are most abundant from May to December each year. They make the sweet potatoes stink so badly that you cannot eat them at all!" says sweet potato farmer Hong Xiang. In the past, if farmers wanted to eliminate sweet potato weevils, they either sprayed pesticides or destroyed the sweet potatoes infested by the weevils. Recently, the Taiwan Agricultural Chemicals and Toxic Substances Research Institute under the Council of Agriculture announced the technology transfer of a "sweet potato weevil sex pheromone microtube attractant," which can attract and trap male weevils, achieving a control effect of 55% to 65%.

Farmers: The Council of Agriculture must promote this vigorously; a few people doing it will not have much effect

Upon hearing about the method above, sweet potato farmers said that the "sweet potato weevil sex pheromone attractant" did not seem to be a new approach; they had heard about it as early as fifteen or sixteen years ago. In response, Hong Qiaozhen candidly admitted that this control method had indeed been developed as early as twenty years ago, but because farmers at the time still mostly relied on spraying pesticides, the sweet potato weevil sex pheromone attractant was not vigorously promoted. "It is only now that everyone is promoting organic farming and advocating against pesticide spraying that we have begun technology transfer," the Agricultural Chemicals and Toxic Substances Research Institute said.

Hong Qiaozhen stated that if sex pheromones are used to trap sweet potato weevils, it is estimated that each hectare of sweet potato field can reduce pesticide applications by 1 to 3 times, and control costs can be reduced by 3,000 yuan to 13,000 yuan. Faced with the institute's optimistic estimate, Hong Xiang pointed out that the trapping effect of sex pheromones is indeed good, "but the key is that 'everyone must use it together' for it to be effective." Otherwise, if only one farmer uses the sex pheromone trapping method while neighboring farmers do not, sweet potato weevils may still come into one's own field.

"Doing these things is not very difficult, but the key is that the Council of Agriculture must find ways to teach farmers and farmers' associations must find ways to promote it. Otherwise, if only a few people do it, the effect will not be great," Hong Xiang said. Hong Qiaozhen deeply agreed, saying, "To do sex pheromone trapping, the larger the area, the more effective it is." Educational workshops may be held afterward to strengthen promotion.