Consequences for Australian biodiversity with establishment of the Asiatic Citrus Psyllid, Diaphorina citri, under present and future climates

The exotic Asiatic Citrus Psyllid, Diaphorina citri, would pose a significant threat to the Australian citrus industry and Australia's unique (and often rare or threatened), native biodiversity were it to become established due to its ability to vector the debilitating bacterial disease huanglongbing. It is not known if Australia's six indigenous Citrus spp. and other Rutaceae are potential hosts for D. citri, or whether the psyllid could transmit the disease to them. We also do not know whether native psyllids, some of whose host plant relationships are yet to be established, could also harbour and transmit the disease. We examine the consequences of D. citri in Australia to native Rutaceae and psyllids. The situation is further compounded by climate change which will impact the likely establishment and spread of the psyllid. Predictive modelling suggests southern locations would be more suitable for the successful development of the psyllid but that a shortened period when plants are available for feeding would actually result in a reduction in overall potential population. Research priorities for determining the degree of risk posed by the introduction and establishment of D. citri are outlined, including the potential impact of climate change.