Cotton Growers Urged Timely Action Against Pink Bollworm Threat
The agriculture experts have urged cotton growers to intensify field monitoring and adopt timely integrated pest management measures to prevent the pest from turning into a major production setback as the pink bollworm is posing a serious threat to cotton yield.
A spokesman of Agriculture (Extension) department warned that pink bollworm attacks cotton flowers, bolls, and seeds, and in severe infestations, can reduce crop yield by up to 30 percent. The growers have therefore been advised to:
- Conduct pest scouting in their fields at least twice a week.
- Install pheromone traps for early detection and effective monitoring of the pest. (Around one trap per five acres for monitoring and eight to 10 traps per acre for management, depending on infestation level and expert recommendations.)
For field diagnosis, growers should select 20 tender bolls (14-18 days old) from different parts of the field, observe them for 3-4 days, and subsequently open and examine the bolls for the presence of pink bollworm larvae.
Chemical control is necessary when infestation reaches the economic threshold level (ETL). If approximately 5% or more infestation is detected in 100 bolls, growers should seek expert advice and use only registered pesticides recommended by the Agriculture Department. Suggested pesticides include:
- Spinetoram: 100 millilitres per acre
- Chlorantraniliprole + Lambda-cyhalothrin: 160 millilitres per acre
- Gamma-cyhalothrin: 100 millilitres per acre
Two to three sprays may be applied at intervals of 6-7 days, subject to registered label and departmental recommendations.
Non-chemical measures include:
- Removing and destroying affected rosette flowers
- Avoiding unnecessary pesticide applications
- Rotating insecticides belonging to different chemical groups to prevent pesticide resistance
Destruction of cotton crop residues and remaining bolls after harvesting is also crucial, as pink bollworm can complete its life cycle in leftover plant material, leading to subsequent infestations.
Timely destruction of crop residues, effective off-season management, and pheromone-based integrated pest management (IPM) measures are essential to reducing pink bollworm pressure and protecting cotton productivity.
