Assessing the risk of novel pesticide resistances entering Australia

Abstract The spread of novel pesticide resistances in arthropod pests poses a growing threat to agricultural industries worldwide. In this study, we developed a framework to assess the risk of novel pesticide resistance incursions into Australia, using the grains industry as a case study. By integrating data on overseas pest resistance patterns and international trade volumes, we identified key pathways and countries that pose significant biosecurity risks to Australia. To validate our generalised approach, we estimated propagule pressures for green peach aphids ( Myzus persicae ) using Australian border interception data from 2010 to 2017. Our analysis identified 20 arthropod species with novel resistances occurring overseas that have the potential to spread to Australia. We estimated the greatest risk of resistance incursion is associated with the trade of live plant material, particularly cut flowers and fresh produce, due to both high import volumes and the suitability of these commodities as hosts for many important pest species. Among the countries analysed, China poses the highest risk due to its substantial trade volumes of suitable host material imported to Australia, as well as the large number of pest species with novel resistances in that country. Our framework provides a valuable tool for guiding biosecurity efforts aimed at minimising the entry of novel pesticide resistances, with potential applications beyond the grains industry. The entry and spread of pesticide‐resistant biotypes present a significant and growing threat to Australian agriculture, particularly for industries that rely heavily on chemicals for pest control.