title: Toxicity risk of insecticides to the insect egg parasitoid Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae).
abstract: BACKGROUND
  Natural populations of Trichogramma evanescens contribute to the control of lepidopterous pests. The toxic effects of insecticides have been extensively reported on trichogrammatids, but are largely unknown on T. evanescens. In this study, the toxicities of seven classes of chemicals against the parasitoid were investigated.
  
  
  RESULTS
  Among these classes, organophosphates and carbamates exhibited the highest levels of intrinsic toxicity, with LC50 values ranging from 0.025 (0.023-0.028) to 2.20 (1.71-3.09) and from 0.040 (0.032-0.053) to 1.84 (1.53-2.30) mg AI L(-1) respectively. Among the phenylpyrazoles, only ethiprole can be considered to be less toxic in the group. Avermectins, pyrethroids and neonicotinoids were less toxic, with LC50 values ranging from 1.29 to 2.57, from 2.26 to 14.03 and from 1.12 to 239.1 mg AI L(-1) respectively. In contrast, insect growth regulators (IGRs) showed the lowest toxicity to the parasitoid, with LC50 values ranging from 3383 (2406-5499) to 5650 (4228-8579) mg AI L(-1) .
  
  
  CONCLUSIONS
  The results of risk quotient analysis indicated that neonicotinoids, avermectins, pyrethroids and IGRs were less hazardous, but phenylpyrazoles (except for ethiprole), organophosphates and carbamates were slightly to moderately or dangerously toxic to T. evanescens. The present results provide informative data for implementing biological and chemical control strategies in integrated pest management of lepidopterans.
authors: State Key Laboratory Breeding Base for Zhejiang Sustainable 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, Zhejiang, China.
authors: Yanhua
authors: Y
authors: Wang
authors: Changxing
authors: C
authors: Wu
authors: Tao
authors: T
authors: Cang
authors: Lizhi
authors: L
authors: Yang
authors: Weihua
authors: W
authors: Yu
authors: Xueping
authors: X
authors: Zhao
authors: Qiang
authors: Q
authors: Wang
authors: Leiming
authors: L
authors: Cai
mesh_terms: D000818:Animals; D007306:Insecticides / Q000633:toxicity*; D007915:Lepidoptera / Q000469:parasitology; D010063:Ovum / Q000187:drug effects* / Q000254:growth & development; D010572:Pest Control, Biological; D014863:Wasps / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology
chemical_list: D007306:Insecticides
keywords: chemical control; conservation biological control; insecticide toxicity; integrated pest management