Faisalabad: 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 and install pheromone traps for early detection and effective monitoring of the pest, he added.
He said that 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, depending on the level of infestation and expert recommendations.
For field diagnosis, the growers have been advised to 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. The bolls should subsequently be opened and examined for the presence of pink bollworm larvae, he added.
He said that 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, he added.
He recommends Spinetoram at 100 millilitres per acre, Chlorantraniliprole + Lambda-cyhalothrin at 160 millilitres per acre, or Gamma-cyhalothrin at 100 millilitres per acre, mixed in 100 litres of water, subject to the registered label and departmental recommendations. Where necessary, two to three sprays may be applied at intervals of six to seven days on the advice of agricultural experts, he added.
He stressed the importance of non-chemical measures, including removing and destroying affected rosette flowers, avoiding unnecessary and excessive pesticide applications, and rotating insecticides belonging to different chemical groups to help delay the development of pesticide resistance.
He also emphasized the use of pheromone traps, removal of infested rosette flowers and application of effective registered insecticides only when the economic threshold level is reached.
Emphasizing the importance of off-season management, he advised the growers to 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.
He said 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.
He urged growers not to resort to self-prescribed or unregistered pesticides in case of an infestation. Instead, they should immediately contact Agriculture Department field staff or qualified experts and use only recommended and registered pesticides in accordance with the economic threshold level, he added.
He stressed that regular scouting, early detection and timely intervention could play a decisive role in containing pink bollworm before it causes significant damage to the cotton crop.
