Abstract:  【Aim】 This study aims to investigate the biological characteristics of the parasitoid Leptopilina boulardi and to determine the effects of its parasitism on the growth and development of host Drosophila melanogaster. 【Methods】 The developmental duration and parasitism efficiency of L. boulardi were detected by anatomical imaging and statistical analysis. The changes of developmental duration and pupal body length and weight of host D. melanogaster after being parasitized by L. boulardi were also investigated. 【Results】 The results showed that the mean duration of egg stage, larval stage and pupal stage of L. boulardi was 0.98±0.22, 10.22±0.57 and 8.09±0.19 (male pupa) or 10.07±0.30 (female pupa) d, respectively. The female takes about two more days to complete pupal eclosion than the male. After the 2nd instar larvae of D. melanogaster were parasitized by L. boulardi, the cellular encapsulation response occurred obviously in D. melanogaster larvae, the larval duration of D. melanogaster was prolonged, and the pupal body length and weight of D. melanogaster were also significantly reduced. 【Conclusion】 L. boulardi is a specialist parasitoid of D. melanogaster. The results provide the experimental basis for studying the mechanisms of wasps regulating their hosts.

Key words:  Leptopilina boulardi, Drosophila melanogaster, parasitism, growth and development, biological control