Pest attack on coconut trees worries TN farmers

MADURAI: Coconut farmers in the state are distressed by the rampant increase of whitefly attacks and have called upon experts and officials to find ways to remedy the situation.

T Perumal, national vice president, Bharatiya Kisan Sangh in Vadipatti, shared his woes and knowledge of the pest attack. According to him, whiteflies are well entrenched in parts of Pollachi, Udumalaipettai and Coimbatore, and now the pests are gradually spreading to plantations of Madurai and its neighbours.

He asked for solutions for the situation, as over a thousand trees in Pollachi were destroyed by the pests, prompting many farmers to put up a distress sale.

T Abdul Razakm, head of Entomology department at VOC Agricultural College and Research Institute, Thoothukudi, said Rugose spiralling whitefly, a sucking pest, has caused significant yield loss in recent years across all southern states. It was first found in Belize, a North American country, in 2004. In India, it was first noticed in 2016 in Pollachi and Kottayam (Kerala).

Later, it was also found in Tiruppur, Erode, Theni, Pudukottai, Kanniyakumari and Tirunelveli districts, Razak told DT Next.

"Its eggs are laid in a spiral pattern with a waxy secretion on the undersurface of the leaves. Nymphs and adults suck the sap on the undersurface of the leave causing an enormous quantity of honeydew secretion to fall on the upper part of leaves leading to mould infection. This disrupts photosynthesis, stunting the growth of the nut," Razak explained.

Banana, guava, citrus, mango, sapota, jack, papaya, lady's fingers, colocasia, tapioca, jatropha and parthenium weed are among 140 plants affected by this whitefly species. The lifetime of this species' adult is 22 to 25 days.

He also mentioned that the 'Dwarf’ and ‘TxD’ hybrid coconuts were heavily damaged when compared with tall varieties.

POINT BOX

Remedies to protect trees from the whiteflies

Pressure-spray the undersurface of leaves to clear off eggs

Install yellow polythene sheets smeared with castor oil around coconut tree trunks and between two adjacent trees at 6 ft height

Reapply castor oil in intervals to retain stickiness - this attracts and kills adult whiteflies

Nymphal parasitoid ‘Encarsia’ wasps should be released at ten leaf bits per acre.

Intercrops such as banana, Canna indica and custard apple could be raised inside coconut gardens to sustain the parasitoid activity.

Apply recommended fertilisers periodically to boost the vigour of the tree

Chemical insecticide, either as spray or root feeding, is discouraged