title: Susceptibility to neonicotinoids and risk of resistance development in the brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae).
abstract: BACKGROUND
  In recent years, outbreaks of the brown planthopper, Nilaparvata lugens (Stål), have occurred more frequently in China. The objective of this study was to determine the susceptibility of N. lugens to neonicotinoids and other insecticides in major rice production areas in China.
  
  
  RESULTS
  Results indicated that substantial variations in the susceptibility to different insecticides existed in N. lugens. Field populations had developed variable resistance levels to neonicotinoids, with a high resistance level to imidacloprid (RR: 135.3-301.3-fold), a medium resistance level to imidaclothiz (RR: 35-41.2-fold), a low resistance level to thiamethoxam (up to 9.9-fold) and no resistance to dinotefuran, nitenpyram and thiacloprid (RR < 3-fold). Further examinations indicated that a field population had developed medium resistance level to fipronil (up to 10.5-fold), and some field populations had evolved a low resistance level to buprofezin. In addition, N. lugens had been able to develop 1424-fold resistance to imidacloprid in the laboratory after the insect was selected with imidacloprid for 26 generations.
  
  
  CONCLUSIONS
  Long-term use of imidacloprid in a wide range of rice-growing areas might be associated with high levels of resistance in N. lugens. Therefore, insecticide resistance management strategies must be developed to prevent further increase in resistance.
authors.affiliation: Key Laboratory of Monitoring and Management of Plant Disease and Insects, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China.
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Wang
authors.forename: Jin
authors.initials: J
authors.lastname: Chen
authors.forename: Yu Cheng
authors.initials: YC
authors.lastname: Zhu
authors.forename: Chongyong
authors.initials: C
authors.lastname: Ma
authors.forename: Yue
authors.initials: Y
authors.lastname: Huang
authors.forename: Jinliang
authors.initials: J
authors.lastname: Shen
mesh_terms: D000691:Anabasine / Q000031:analogs & derivatives; D000818:Animals; D006430:Hemiptera / Q000187:drug effects* / Q000235:genetics; D007093:Imidazoles / Q000494:pharmacology*; D007305:Insecticide Resistance / Q000235:genetics; D007306:Insecticides / Q000494:pharmacology*; D007928:Lethal Dose 50; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000494:pharmacology*; D012275:Oryza / Q000469:parasitology; D011720:Pyrazoles / Q000494:pharmacology; D012641:Selection, Genetic; D013829:Thiadiazines / Q000494:pharmacology
chemical_list: D007093:Imidazoles; D007306:Insecticides; D000073943:Neonicotinoids; D009574:Nitro Compounds; D011720:Pyrazoles; D013829:Thiadiazines; C083997:buprofezin; C082359:imidacloprid; D000691:Anabasine; C082360:fipronil