Gall Associates of the Mekong region and Australia, their distribution and hosts: ACIAR Report

Since 2014, surveys have been conducted across Lao PDR, Cambodia, Thailand and Vietnam, providing information of the presence of Leptocybe spp. and the associated parasitoid Quadrastichus mendeli. Although Q. mendeli is widespread through the region the introduction of additional biological control agents is required to improve control of the pest, based on the experience in Israel where establishment of four parasitoids has supported very high levels of control. Redistribution of Q. mendeli will take place in areas of high pest pressure, based on the findings from the field surveys. These areas will potentially be release sites for Selitrichodes neseri in 2017. No other natural enemies with the potential to manage Leptocybe spp. have emerged from the Mekong gall material. Surveys across Australia have failed to find Leptocybe invasa, but the undescribed Leptocybe sp. that is also present in the Mekong region was collected throughout north-eastern Australia. Collections from northern Queensland to northern New South Wales have determined that Megastigmus spp. may be another important parasitoids of the gall wasp.