Insecticide Resistance of Chilli thrips (Scirtothrips dorsalis) during Mango Cultivation in the Republic of Korea

Chilli thrips (Scirtothrips dorsalis) is a type of serious pest causing a significant damage during mango cultivation in Korea.Control is mainly achieved through the intense application of insecticides, a practice that facilitates the development of insecticide resistance worldwide.We evaluated the resistance of chilli thrips collected from mango cultivation areas in Korea to eight registered insecticides: abamectin 1.8% EC, bifenthrin 2% WP, chlorfenapyr 5% EC, cyantraniliprole 10% SE, dinotefuran 20% WG, emamectin benzoate 2.15% EC, spinetoram 5% SC, and thiacloprid 10% SC.Bifenthrin encountered relatively high resistance, requiring over 4 times the recommended concentration (RC) to produce 90% mortality, in all regions, and high levels of resistance to dinotefuran and thiacloprid were observed in all regions.On the other hand, spinetoram encountered low resistance levels in all regions.Emamectin benzoate was also highly effective, producing LC 90 values below the RC in all regions except Jangheung.Chlorphenapyr encountered low resistance levels in Jeju-si and Haenam-gun, but high resistance was recorded in Tongyeong-si.Cyanthraniliprole faced moderate to high resistance in all regions.These findings suggest that there is a need to establish an effective control system for chilli thrips, which would require the continuous monitoring of regional insecticide resistance.