Abstract:Anastatus japonicus(Ashmead) is an efficient egg parasitoid against Tessaratoma papillosa(Drury), a major litchi(Litchi chinensis)pest,in Southern China.However, the practical biocontrol efficacy of A.japonicus mass produced using middle host Antheraea pernyi eggs is low in field.It is known that parasitoids response to a host can be affected by the experience on host cues gained during and immediately after emergence from the host.Does the experience in middle host affect the host selection process of A.japonicus? If so, how long does it last? It is unknown whether experiences trained on natural host cues will improve the responses of a parasitoid raised by middle host to its natural host.In this study, first of all, we investigated the memory persistence of mated and unmated A.japonicus for information from middle host eggs (Antheraea pernyi eggs) at different times after eclosion.Secondly, we compared the selectivity of trained and untrained A.japonicus on natural host (Tessaratoma papillosa eggs) and middle host (Antheraea pernyi eggs) at different times post-emergence.Finally, we evaluated the searching efficiency of A.japonicus after learning experiences in processing T.papillosa egg.The results showed that the time and the amount of inspecting host eggs of mated A.japonicus were increased significantly after A.japonicus had emerged from the middle host eggs 96h later.We observed that the time for searching host eggs for unmated A.japonicus was also delayed remarkably, therefore the memory of A.japonicus for information from A.pernyi eggs began to weaken distinctly after 96 h.On the other hand, the number of first-selectivity for T.papillosa eggs and the amount of poking T.papillosa eggs for trained and untrained A.japonicus were increased obviously at 96 h after emergence.Interestingly, the number of first-selectivity for T.papillosa eggs and the amount of inspecting and poking T.papillosa eggs for trained A.japonicus were more than those of untrained A. japonicus at different times post-emergence. The results showed that trained A. japonicus has higher attraction to T. papillosa eggs compared to untrained A. japonicus, and the interfering information from middle host A. pernyi decreased gradually.