Abstract: 【Aim】 Aphelinus maculatus is a newly recorded species in China in 2016, and one of the most important parasitoids of the peach aphid, Myzus persicae. In order to evaluate the control ability of A. maculatus to M. persicae scientifically,we investigated the effects of the ovipositor stabbing of A. maculatus on the survival, development and fecundity of its host peach aphid. 【Methods】 M. persicae aphids stabbed by the ovipositor (ovipositor insertion into aphid body and withdrawing out once) of A. maculatus were reared individually on the rape leaf-let in the petri-dish. The number of survival individuals, number of parasitized individuals, and number of death individuals of M. persicae, and the development and reproduction of the survivors were recorded daily until the death of the aphid.【Results】The effects of the ovipositor stabbing of A. maculatus on peach aphid included lethal, survival and parasitism. The mortality of peach aphid stabbed by the ovipositor of A. maculatus decreased with the increase of peach aphid age, and that of the 1-day-old nymphs stabbed by ovipositor of A. maculatus was the highest (45%). The longer the stabbing time, the higher the mortality of the peach aphid. The survival rate of peach aphid and parasitism rate of A. maculatus increased with the increase of the peach aphid age. The nymphal survival period and pre-reproduction duration of survival peach aphid were longer than that of the control (not being stabbed), but the reproduction duration and post-reproduction duration were significantly shorter than that of the control. The reproduction duration of the 3-day-old nymphs stabbed by the ovipositor of A. maculates was the shortest, being shortened by 13.7±1.7 d as compared to that of the control. The adult longevity of survivors of the peach aphid stabbed by the ovipositor of A. maculatus was significantly shortened and related to the age of peach aphid when being stabbed. The adult longevity of the 2-day-old and 3-day-old nymphs stabbed by the ovipositor of A. maculates was impacted greatly, being shortened by 12.5 and 11.2 d, respectively, as compared to that of the control. The fecundity (number of offspring produced per aphid) of the stabbed survivors decreased significantly, and the younger the stabbed age, the fewer the fecundity. The stabbed survivors from the 1dayold nymphs and adults produced 39.1±4.9 and 25.2±2.7 offspring fewer than their nonstabbed controls, respectively. 【Conclusion】In addition to parasitism and feeding on peach aphid, ovipositor stabbing (unsuccessful parasitization) by A. maculatus will prolong the growth and development phase of survival peach aphid and reduce its life span and fecundity. These effects of the ovipositor stabbing of A. maculatus on the survival, development and fecundity of its host may play important roles in evaluation of its aphid control ability.

Key words: Aphelinus maculatus, Myzus persicae, unsuccessful parasitization, survivor, development, fecundity