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 pheromone trap per five acres may be used for monitoring, while eight to 10 traps per acre can be deployed for management purposes.
- For field diagnosis, select 20 tender bolls (approximately 14 to 18 days old) from different parts of the field and keep them under observation for three to four days. Subsequently, examine the bolls for the presence of pink bollworm larvae.
Chemical control becomes necessary when infestation reaches the economic threshold level (ETL). If approximately five percent or more infestation is detected in 100 bolls, the growers should seek expert advice and use only registered pesticides recommended by the Agriculture Department. Some recommended pesticides include:
- Spinetoram at 100 millilitres per acre.
- Chlorantraniliprole + Lambda-cyhalothrin at 160 millilitres per acre.
- Gamma-cyhalothrin at 100 millilitres per acre.
Two to three sprays may be applied at intervals of six to seven days, subject to registered label and departmental recommendations.
Non-chemical measures, including removing and destroying affected rosette flowers, avoiding unnecessary pesticide applications, and rotating insecticides, should also be emphasized to help delay the development of pesticide resistance.
The importance of off-season management cannot be overstated. Growers should destroy cotton crop residues and remaining bolls after harvesting, as pink bollworm can complete its life cycle in leftover plant material and subsequently infest the next cotton crop. 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.
