Study on the field propagation of Pteromalus sanjiangyuanicus Yang and its biological control of Gynaephora qinghaiensis

•The propagation of natural enemies in the field environment.•Gynaephora qinghaiensis pupae as the host for propagation of natural enemies.•The artificial nest made of coconut shell has a good propagation effect.•The biocontrol effect of Pteromalus sanjiangyuanicus was very significant.