Alappuzha: Water hyacinths is an invasive floating plant that often destroys the natural beauty and ecology of the famed backwaters of Alappuzha. Now, an experiment using an insect that feeds on water hyacinth has proved to be a roaring success. The International Research and Training Centre for below Sea Level Farming in Kuttanad used neochetina weevils, a locally discovered biocontrol agent, for genetically controlling the growth of water hyacinths. The weevils were released in the lake and smaller streams on an experimental basis. As the experiment has been declared a grand success, the neochetina weevils have been released in more than 100 spots across the district. Water hyacinths were found to be either destroyed or dried up in huge amount at these spots. 

Organic and genetic methods were tried under the water hyacinth control project launched by the central government’s Rashtriya Krishi Vikas Yojana. Meanwhile, the neochetina weevils that are generally found in South America were discovered in some parts of the Vembanad Lake. 

By mid-2025, the weevils were grown in huge numbers in the laboratories and then released into the lake at various spots. The research report states that this method doesn’t harm the ecology as these beetles would get eliminated or eaten by fish when the water hyacinths disappear. 

The neochetina weevils have destroyed large patches of thickly grown water hyacinths in Kuttanad region as well as in Arookkutty. Huge swathes of water hyacinths were found dried up in the Chenganda lake. The dried water hyacinths are removed by the currents, reviving the natural flow of water in the lakes. As growing the beetles in laboratories is a time consuming process, neochetina weevils were collected from various parts of the lake and released in areas where they are not seen. 

Research project worth Rs 13 crore is being conducted at the centre for eliminating water hyacinths from the backwaters. Research centre director Dr. KG Padmakumar said that the proliferation of water hyacinth could be effectively prevented only by reviving the natural water flow of the water and controlling the growth of flora in the lake.