Abstract: 【Aim】 This study aims to clarify the side effects of clothianidin and its two mixtures to Apis mellifera ligustica and Trichogramma ostriniae. 【Methods】 The acute toxicity of clothianidin and its two mixtures to adult workers of A. mellifera ligustica and adult T. ostriniae was determined in the laboratory, and the safety of these insecticides was evaluated. 【Results】 Stomach toxicity tests performed in standardized conditions on adult bees showed that clothianidin insecticides had very high toxicity to the adult workers of A. mellifera ligustica, with the LC₅₀ values of 0.0200 (0.0143-0.0272) for 30% clothianidin SC, 0.0847 (0.0658-0.1157) for 30% pymetrozine·clothianidin SC and 0.1594 (0.1200-0.2056) mg a.i./L for 20% ethofenprox·clothianidin SC, respectively. The LC₅₀  values of 30% clothianidin SC, 30% pymetrozine·clothianidin SC and 20% ethofenprox·clothianidin SC against adult workers of A. mellifera ligustica at 48 h after topical application were 0.0155 (0.0114-0.0197), 0.0426 (0.0335-0.0539) and 0.1122 (0.0796-0.1385) μg a.i. per bee, respectively. All the tested insecticides showed high contact toxicity to adult workers of A. mellifera ligustica. Toxicity of test insecticides to adult T. ostriniae  determined by using dry film residue method under laboratory conditions showed that the LC₅₀  values (24 h) of 30% clothianidin SC, 30% pymetrozine·clothianidin SC and 20% ethofenprox·clothianidin SC against adult T. ostriniae were 0.0232 (0.0180-0.0295), 0.1050 (0.0940-0.1170) and 0.0059 (0.0054-0.0065) mg a.i./L, respectively. The results of safety evaluation showed that 30% clothianidin SC, 30% pymetrozine·clothianidin SC and 20% ethofenprox·clothianidin SC were ranked as very high risk to adult T. ostriniaewith the safety factors of 5.95×10^-4, 2.69×10^-3 and 9.50×10^-5, respectively. 【Conclusion】 Clothianidin and its two mixtures have high risk of acute toxicity to both A. mellifera ligustica and T. ostriniae, so the use of these insecticides should be evaluated carefully in integrated pest management (IPM) programs.

Key words: Apis mellifera ligustica; , Trichogramma ostriniae, clothianidin, stomach toxicity, contact toxicity, dry film residue method, acute toxicity, safety evaluation