Evaluation of flubendiamide and bacillus thuringiensis (Btk) for controlling metisa plana and economic impact of severe infestation on oil palm yield / Che Ahmad Hafiz Che Manan

In Malaysia, Bagworms, Metisa plana are one of the most serious and critical pests on oil palm. Most approaches were still not promising for planters to decide as the primary solution for bagworm control. Therefore, it is important to identify cost-effective pesticide with simultaneous good control efficiency alongside different treatment methods. This research aimed to evaluate the cost-effectiveness for two types of pesticide (Bacillus thuringiensis and Flubendiamide) and methods of spraying application also the impact of bagworm infestation on oil palm yield. The first treatment by Aircraft (aerial), application at 30 and 50 liters per hectare and second treatment by tractor-mounted sprayer (ground) spray at high and low pest population. Based on the first treatment with aerial spray via aircraft, Flubendiamide was effective (p<0.05) to control M. plana, whereas Bacillus thuringiensis (Btk) not effective (p>0.05) to control M. plana population below economic threshold level (ETL). Second treatment for ground spray via tractor-mounted sprayer with Flubendiamide was more effective (p<0.05) than Btk (p<0.05) at high infestation area. Whereas, in the low infestation area, both Flubendiamide and Btk were comparable (p<0.05) in controlling M. plana below ETL. By evaluating the actual yield loss due to the infestation (37%), the monitoring and treatments cost up at only 2.9% from the total loss suffered. To conclude, based on Benefit-Cost Ratio (BCR), Flubendiamide aerial and ground application is better cost-effective (1:59 & 1:37) than Btk (1:33 & 1:14) to control the M. plana below ETL thus avoiding greater yield loss suffered due to the continuous infestation.