Abstract: In the early 2019, Spodoptera frugiperda invaded Yunnan Province of China and spread rapidly. In order to screen pesticides with high control efficacies to S. frugiperda, the toxicities of 26 commercial pesticides were determined on the newly hatching, third and fifth instar larvae of S. frugiperda in laboratory. The results showed that except for 6% rotenone EC and 0.5% veratrine EC, the corrected mortalities of other pesticides against newly hatching larvae were over 70% after 72 h. Compared to the newly hatched larvae, the toxicities of most pesticides on the third instar larvae decreased. The corrected mortalities of 11 pesticides, including 4.5% lambda-cyhalothrin EC, 1.8% abamectin ME, 20% chlorantraniliprole SC, 0.5% matrine AS, etc, were below 70% after 72 h for the third instar larvae. Eighteen pesticides which had good effects on the third instar larvae were selected to determine their toxicities on the fifth instar larvae. The results showed that except for 30% buprofezin·chlorpyrifos EC, 1.8% abamectin ME, 3.2% lambda-cyhalothrin·emamectin benzoate ME, 56% abamectin·propargite ME, 20% chlorantraniliprole SC and 10% flubendiamide SC, the corrected mortalities of 12 other pesticides against the fifth instar larvae were above 70%, including 6% emamectin benzoate·chlorfenapyr EC, 44% cypermethrin·profenophos EC, 25% profenophos·methomyl EC, 15% indoxacarb SC, 3 billion PIB·mL^-1 cabbage armyworm nuclear polyhedrosis virus SC, 25% emamectin benzoate·chlorbenzuron SC, 2% emamectin benzoate ME, 45% chlorpyrifos EC, 34% spinetoram·methoxyfenozide SC, 5% lufenuron EC, 40% fipronil·spinetoram WG, and 1% celastrus angulatus EC.

Key words: Spodoptera frugiperda, commercial insecticides, toxicity test, insecticidal efficacy