Background: The diamondback moth (DBM), Plutella xylostella (L.), is a cosmopolitan pest of cruciferous crops. Fufenozide, a novel non-steroidal ecdysone agonist, exhibits good efficacy and plays an increasingly important role in the control of Lepidopterous pests in China. A laboratory strain of DBM was selected for resistance to fufenozide, and the genetic basis of resistance was studied.
Results: The resistant strain, selected under laboratory conditions, exhibited a higher level of resistance to fufenozide (302.8-fold based on LC(50)s) than the laboratory susceptible strain. Mortality data from the testing of F(1) progeny of reciprocal crosses of resistant and susceptible DBM indicated that resistance was autosomal and incompletely recessive with a degree of dominance of -0.664. Chi-square analysis from responses of a backcross of crossed F(1) progeny and the resistant strain and F(2) progeny were highly significant, suggesting that the resistance was probably controlled by more than one gene. The estimated realised heritability (h(2)) of fufenozide resistance was 0.08, indicating that diamondback moth may have a lower chance of developing resistance to fufenozide than other kinds of insecticide.
Conclusion: The resistance of DBM to fufenozide might be autosomal and incompletely recessive, and the resistance is probably controlled by more than one gene. These results provide the basic information for pest management programmes.