Effect of antibiotics and gut bacteria on fitness of diamondback moth Plutella xylostella (L.)

Abstract:

[Objective] Diamondback moth (DBM) Plutella xylostella (L.) is the most important pest of cruciferous crops worldwide. The purpose of this study was to find the effect of gut bacteria and antibiotics on the fitness of DBM. [Methods] The radish DBM strain and the germ-free artificial diet DBM strain were reared under antibiotic, and then the effect of gut bacteria and antibiotics on the fitness of DBM was evaluated. [Results] The antibiotic-treatment on the radish DBM strain has reduced hosts' fitness, reflected as retarded development, reduced weights, declined pupation rates, descended fecundity and shorted adult life-span. The antibiotic-treatment on the germ-free artificial diet DBM strain decreased pupation rate and fecundity. [Conclusion] Negative effects on the host fitness after antibiotic treatment was partly caused by the toxic effect of antibiotic and partly by the deficiency of gut bacteria. The gut bacteria may play a promote role in the fitness of DBM.