First report of Amaranthus tuberculatus in Croatia
Amaranthus tuberculatus (Amaranthaceae) is a dioecious summer annual species native to North America, where it has become a weed in agricultural fields and disturbed habitats. It has a high fecundity and a long-lived seed bank which make management of the species difficult. In North America, it is a competitive annual weed in maize, soybean and cotton. At present, transient and established occurrences of the species are known from a number of EPPO countries, mainly on ruderal sites and along riverbanks, and to a lesser extent in crop fields (e.g. EPPO RS 2020/107). Pathways for entry into the EPPO region include contaminant of grain and seeds for planting. In 2019, a botanical survey was conducted in the Pannonian part of Croatia. A. tuberculatus was recorded in a total of 19 locations. Twelve were situated on the banks of the Sava River, distributed along a 76 km long river section, while the remaining locations were close to the river. A. tuberculatus was also recorded on the edges of alluvial forests along the Sava River. Flowering male and female individuals were recorded at all locations. At present, A. tuberculatus has not been detected in agricultural habitats in Croatia. The species should be monitored and controlled to avoid further spread.
Rimac A, Doboš M, Šegota V (2020) Amaranthus tuberculatus (Moq.) J.D. Sauer – a new alien pigweed in Croatia. BioInvasions Records 9, In Press.