Abstract: After artificial selection for resistance to 0.2% celangulin EC for 20 generations, resistance of the diamond back moth, Plutella xylostella (L.) fourth instar larvae to this pesticide increased 21.6-fold. The development of resistance was slow initially, faster in the mid-stage, and stable in the later stage.The celangulin-resistant strain had positive cross-resistance to dimehypo, cartap and isoprocarb (R/S was 4.63, 4.11 and 3.71 respectively), and negative cross-resistance to deltamethrin, cypermethrin and permecthrin (R/S was 0.22, 0.26 and 0.01 respectively). The cartap-, dimehypo- and deltamethrin-resistant strains had 1.06-, 1.76- and 3.61-fold resistance to 0.2% celangulin EC, respectively.

Key words: Plutella xylostella, celangulin, insecticide resistance