April 13, 2025 | DT NEXT |
Coconut farmers in Tamil Nadu are facing increasing distress due to the spread of Rugose spiralling whitefly, a pest that has devastated coconut plantations in Pollachi, Udumalaipettai, Coimbatore, and now Madurai. Over a thousand trees have already been affected in Pollachi, prompting distress sales. The pest, first discovered in Belize in 2004 and in India in 2016, targets over 140 plant species, including bananas, mangoes, guavas, and papayas.
Dr. T Abdul Razak, head of the Entomology Department at VOC Agricultural College, explained that the pest lays eggs in spirals on the undersides of leaves. The nymphs and adults suck sap and secrete honeydew, leading to mould growth that blocks photosynthesis, stunts tree growth, and reduces nut yield. Dwarf and hybrid coconut varieties appear more susceptible than tall ones.
To combat the pest, experts recommend non-chemical measures: pressure-spraying leaves, installing castor oil-coated yellow polythene sheets to trap adult flies, and introducing natural predators like Encarsia wasps. Farmers are also encouraged to plant intercrops such as banana and custard apple to support parasitoid populations, and to apply proper fertilization to strengthen tree health. Chemical insecticides are discouraged to preserve ecological balance and effectiveness of biological controls.