These days a new problem has knocked on the tea gardens of Assam and West Bengal. For the past two years, an insect called ‘Greenfly’ is spreading rapidly and causing severe damage to tea plants. Due to this insect, a decline of 11 percent to 55 percent has been recorded in tea production in many areas. Its infestation is most visible during the summer and dry months.
The most damage occurs during the second flush period
Greenfly particularly attacks the soft green leaves of the plants, causing the surface of the leaves to become uneven, start curling from the edges and turn brown. This is known as ‘rim blight’. The time between May and July, i.e. the second flush period, is most important for tea gardens, because the best quality tea is obtained during this time and more than 30 percent of the annual income comes during this period. But the infestation of greenfly is the highest during this period.
Greenfly is active throughout the year due to change in weather
Tea Research Association secretary Joydeep Phukan said, “The rise in temperature and lack of rainfall due to climate change is increasing the breeding of greenfly. Earlier this insect was seen only between May and July, but now it is active throughout the year. It is feared that this insect has now become capable of withstanding the vagaries of weather.” Apart from this, there is also a danger of the arrival of a modified form of greenfly and more aggressive species in the plantations along the international border.
There is a need for new pesticides, scientists are busy in research
Although chemicals approved under the Plant Protection Code (PPC) are being used in tea gardens, their effect on greenfly is decreasing. This insect has now developed resistance to these medicines. Due to this, tea plants are also falling prey to other diseases like ‘Fusarium Dieback’. The Tea Board of India has suggested nine special chemical formulas in PPC version 16.0 in February 2024, but these are also not providing much relief.
Meanwhile, scientists at the Tocklai Tea Research Institute are working on new strategies to deal with the pest. A compound called ‘clofenapyr 10SC’ is believed to be effective, but its use on tea has not yet been approved by the Central Insecticide Board. The tea industry is now demanding an alternative solution as soon as possible to deal with this crisis.
