Amaranthus palmeri and A. tuberculatus added to the EPPO A2 List
In 2020, an EPPO Expert Working Group (EWG) comprising of experts from the EPPO region and North America met at the EPPO Headquarters in Paris to conduct pest risk analysis on Amaranthus palmeri and A. tuberculatus. Following approval of the PRAs, both species are now included on the EPPO A2 list of pests recommended for regulation as a quarantine pest.
Amaranthus tuberculatus: overall outcome of the PRA is high risk with low uncertainty. The endangered area includes agricultural environments situated to the north and east of the Mediterranean Sea. The high frequency of maize and soybean in the crop rotation system in many EPPO countries is a factor that may facilitate the establishment of A. tuberculatus once the field has become contaminated. The likelihood of further establishment outdoors is very high with a low uncertainty. Establishment in protected conditions is medium with a high uncertainty. Protected conditions, such as in nurseries and polytunnels, may offer appropriate conditions for the development of the pest. The potential for spread within the EPPO region is very high with a moderate uncertainty. Seeds of A. tuberculatus can be moved via agricultural machinery and products (e.g. grains, seeds) within the EPPO region. The potential socio-economic impacts in the EPPO region are high with a moderate uncertainty.
Amaranthus palmeri: overall outcome of the PRA high risk with low uncertainty. The endangered area includes agricultural environments in the Mediterranean area, Middle East area and central Asian area of the EPPO region. Within the EPPO region, the species mostly grows in managed habitats such as ruderal and agricultural environments. A. palmeri can invade many summer crops in particular late sowing crops like maize and soybean. The potential spread within the EPPO region is very high with a low uncertainty. A. palmeri can spread both naturally and via human assisted spread. Seeds of A. palmeri can be moved via agricultural machinery and plant products (e.g. grains, seeds) within the EPPO region. The impacts of A. palmeri in North America are primarily the reduction of crop yields and increased management costs. The potential socio-economic impacts in the EPPO region will be high with a moderate uncertainty.
Sources
EPPO (2020a) Pest risk analysis for Amaranthus palmeri. EPPO, Paris. Available at: https://gd.eppo.int/taxon/AMAPA/documents
EPPO (2020b) Pest risk analysis for Amaranthus tuberculatus. EPPO, Paris. Available at: https://gd.eppo.int/taxon/AMATU/documents