The attack of woolly aphid, a pest that lives on plant fluids, has considerably affected the sugarcane cultivation here.
The disease, locally known as White Aswini, can result in low jaggery production as it sucks the sweet cells of the sugarcane.
A senior agriculture officer here told The Hindu that the disease was first noticed in 2006 and it spread from the sugarcane plants replanted here. Officials suspect that the pest spread from the low lying areas of Tamil Nadu from where the disease-hit plants were brought for plantation in Marayur.
The disease is now fast spreading in some areas.
Rajkumar of Kocharam area whose four-acre cultivation was totally affected with woolly aphids said he had applied pesticides as per the directions of the experts but could not control the disease. The experts of Coimbatore Agriculture University had visited his farm recently.
Murugan, another farmer, said the disease resulted in stagnant growth of the plants, decrease in the quantity of sugarcane juice and subsequent fall in jaggery production.
The farmers said the varieties traditionally cultivated were Manjula and CU-L and the disease was found after the new varieties from Tamil Nadu were used for replanting. It was with the aim of increasing the jaggery production because the growth period of the new verities was only nine months.
The growth period of traditional varieties is 12 months.
Marayur is the main sugarcane field in the district and the Marayur jaggery is famous for its quality.