Josef Holec, Michaela Kolářová, Jaroslav Šuk and Josef Soukup
Department of Agroecology and Crop Production, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, 165 00 Prague 6 – Suchdol, Czech Republic
Ammi majus L. (Apiaceae) is an annual plant native to the southern part of Europe and west Asia. As a neophyte, it can be found in many regions of the world, including both South and North America. It can be grown as an ornamental but it is more often used as a medicinal plant. Wild populations can also be found on arable land, being reported among serious weeds of selected crops in Italy, where it can be found as a weed in wide-row crops, such as maize, sunflower or sugar beet (Onofri & Tei 1994, Barberi et al. 1997). In Argentina, the plant colonizes abandoned fields (Boccanelli et al. 1999). It was collected in the territory of the Czech Republic in 1898 for the first time and it is currently classified as a casual neophyte (Pyšek et al. 2012).
We detected this species in 2017 on an arable field with vegetables in close proximity to Straky (Polabí region). Ammi majus occurred on 20 ha field comprising hundreds of individuals, most of which were fertile with fully developed seeds. The patchy occurrence and high density shows that the species was present at this site for several years, but we were not able to find other individuals in the neighbouring fields. Ammi majus can survive and reproduce under current climatic conditions in the Czech Republic and it can act as a weed in wide-row crops. Therefore, this species has the potential to spread in warmer regions with higher concentration of vegetables and sugar beet in crop rotations.
Barberi P., Silvestri N. & Bonari E. (1997) Weed communities of winter wheat as influenced by input level and rotation. Weed Res. 37: 301–313.
Boccanelli S. I., Pire E. F. & Torres P. S. (1999) Vegetation changes in field abandoned after a wheat crop. Pesq. Agropec. Brasil. 34: 151–157.
Onofri A. & Tei F. (1994) Competitive ability and thresholds levels of 3 broadleaf weed species in sunflower. Weed Res. 34: 471–479.
Pyšek P., Danihelka J., Sádlo J., Chrtek J. Jr., Chytrý M., Jarošík V., Kaplan Z., Krahulec F., Moravcová L., Pergl J., Štajerová K. & Tichý L. (2012) Catalogue of alien plants of the Czech Republic (2nd edition): checklist update, taxonomic diversity and invasion patterns. Preslia 84: 155–255.