Pheromone trap method for pest control gaining popularity in Chattogram

Vegetable farmers in Chattogram are being converted to an environmentally friendly and cost-effective method of pest control which uses insects’ own hormones to prevent their spread. Known as “sex pheromone trap,” the method protects human health and the environment and has been dubbed by agriculturists as a “silent revolution in pest control management”. In a sex pheromone trap, a capsule containing the female sex hormones of insects is hung in a plastic bottle which is half-filled with soapy water and has two holes cut in the side to allow the insects to enter. When the bottle is hung in a crop field from two bamboo sticks, the hormones attract male insects which then drown in the soap water, checking the reproduction of the pests. According to data provided by the Department of Agricultural Extension (DAE), from 2015-16 to 2016-17 the number of pheromone traps set up on farmland in Chattogram almost doubled, from 32,000 to 62,000. Aminul Haque Chowdhury, deputy director of Chattogram DAE, told the Dhaka Tribune that farmers, particularly vegetable growers, are increasingly inclined to adopt the new pest control method. “The farmers are now showing much interest in using the pheromone trap instead of harmful pesticides, since it costs less and protects the environment as well,” he said. Aminul said the DAE has fixed a target for setting up 100,000 pheromone traps on agricultural land in Chattogram by the end of 2017-18. “We are hopeful of achieving the target,” he said. The pheromone traps are proven to be an effective pest control solution for vegetables like aubergine, pumpkin, okra, cauliflower, cabbage, bottle gourd, ribbed gourd, teasel gourd, sponge gourd, snake gourd, aubergine, palwal and bean.

Cost-benefit analysis

For aubergine, growers will typically spray heavy doses of toxic pesticide twice a week to protect their crop against repeated pest attacks. But this is not a cost effective method: each round of pesticide spraying costs Tk5,000 per acre of land and with 40 rounds needed in the five or six months it takes to harvest aubergine, the total cost will be Tk2 lakh. Pheromone traps, by contrast, cost only Tk50-60 each, with 125 needed for one acre of farmland. An aubergine grower using this pest control method will therefore only spend Tk7,500 per acre of land – a saving of Tk192,500 over using insecticide. Aminul said the economic value of using environment-friendly pest control methods like pheromone traps is “incalculable.” “If you take the health hazards and ecological damages into account, then the benefit of the pesticide free method is enormous,” the DAE official said.