›› 2012, Vol. 55 ›› Issue (1): 36-45.doi:

• RESEARCH PAPERS • Previous Articles     Next Articles

Acute toxicity and safety evaluation of neonicotinoids and macrocyclic lactiones to adult wasps of four Trichogramma species (Hymenoptera: Trichogrammidae)

WANG Yan-Hua, YU Rui-Xian, ZHAO Xue-Ping, AN Xue-Hua, CHEN Li-Ping, WU Chang-Xing, WANG Qiang   

  1. State Key Laboratory Breeding Base for Zhejiang Sustainable Plant Pest and Disease Control, Key Laboratory for Pesticide Residue Detection of Ministry of Agriculture, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
  • Received:2011-09-15 Revised:2011-11-21 Online:2012-01-20 Published:2012-01-20
  • Contact: ZHAO Xue-Ping E-mail:zhaoxueping@tom.com
  • About author:wangyanh79@163.com

Abstract: To clarify the side effects of insecticides on trichogrammatid wasps, acute toxicities of neonicotinoids and macrocyclic lactiones to adult Trichogramma japonicum Ashmead, Trichogramma ostriniae Pang et Chen, Trichogramma confusum Viggiani and Trichogramma evanescens Westwood were determined by using the dry film residue method under laboratory conditions, and the safety of these insecticides was also evaluated. Among the neonicotinoids tested, thiamethoxam showed the highest intrinsic toxicity to T. confusum and T. japonicum with the LC50 values of 0.24 (0.21-0.27) and 0.40 (0.37-0.44) mg a.i./L, respectively. Nitenpyram had the less toxicity to T. confusum and T. japonicum with the LC50 values of 0.83 (0.74-0.96) and 0.72 (0.65-0.80) mg a.i./L, respectively. Imidacloprid exhibited the least toxicity to T. ostriniae and T. confusum with the LC50 values of 502.13 (459.80-549.62) and 752.62 (687.51-828.63) mg a.i./L, respectively. Among the macrocyclic lactiones selected, abamectin showed the highest toxicity to T. japonicum with the LC50 of 0.49 (0.46-0.65) mg a.i./L, whereas emamectin benzoate had the lowest toxicity to T. confusum with the LC50 of 21.76 (19.59-24.40) mg a.i./L. Results of safety evaluation showed that imidacloprid, acetamiprid, imidaclothiz and emamectin benzoate were classified as low to moderate risk with the safety factor of 0.57-23.54, and thiacloprid and ivermectin were ranked as moderate to high risk with the safety factor of 0.16-3.45, while nitenpyram, thiamethoxam and abamectin were classified as high to extremely high risk with the safety factor of 0.01-0.15. Most of the insecticides here tested have the potential risk of acute toxicity, so the use of neonicotinoids and macrocyclic lactiones, especially for nitenpyram, thiamethoxam and abamectin, should be evaluated carefully in integrated pest management (IPM) programs for avoiding serious damages to trichogrammatid wasps.

Key words: Trichogramma spp., insecticides, neonicotinoids, macrocyclic lactiones, toxic side effects, egg parasitoids, acute toxicity, safety evaluation

CLC Number: 

  • Q965.9