TN agri dept takes action as 1.9 lakh acres of coconut farms hit by whitefly infestation

Out of the 12 lakh acres under coconut cultivation in Tamil Nadu, approximately 1.9 lakh acres have been impacted by the rugose spiraling whitefly, an invasive species known for its rapid spread.

These pests produce a thick sap on the surface of leaves, inhibiting plant growth and threatening coconut yields.

Officials from the Agriculture Department emphasised that only natural and integrated pest management methods can effectively control the infestation.

The Union Government's Department of Agriculture has also advised against the use of chemical pesticides, warning that they may exacerbate the whitefly problem.

To raise awareness and guide farmers, the state has conducted 330 camps across various districts.

A joint field study conducted by scientists from the Central Plantation Crops Research Institute (CPCRI) in Kasaragod, Kerala, the Tamil Nadu Agricultural University (TNAU), and the state's Horticulture Department led to the implementation of several control measures last year, which helped contain the spread.

Research by the Agriculture Department has identified several effective strategies to manage the whitefly population include installation of light traps (one per hectare), use of yellow sticky traps (20 per acre), release of Encarsia parasitoids (100 per plantation), deploying green lacewing insects also called Apertochrysa (400 per acre), spraying a 0.5 per cent neem oil solution and power-spraying water on the underside of coconut leaves.

Meanwhile, farmers in Dharmapuri district -- where coconut cultivation spans around 5,578 hectares --have raised concerns over the growing presence of whiteflies.

They have urged the Horticulture Department to increase awareness efforts and supply biological control agents such as Encarsia formosa, a parasitic wasp known to be effective against whiteflies.

"A coconut tree can grow up to 50 feet, so conventional pest control methods are ineffective," said K.R. Muthumaran, a farmer from Pappireddipatti.

"We need Encarsia mites to control the infestation, but they are not available in our region. The department must step in and provide them," he said.

Agriculture officials said they are promoting awareness through farmer groups and social media campaigns. They have also recommended regular water spraying under the leaves of saplings and young trees up to five years old.

Additionally, a mix of castor oil and water has been suggested as a viable solution, though it is mainly applicable to younger plants.