Seed germination and seedling emergence of Iberian starthistle (Centaurea iberica)

Centaurea iberica has become a problematic weed in some regions of western Iran. Little published data are available in the literature regarding its seed germination and seedling emergence. Therefore, this study was conducted in order to evaluate the effects of different factors on C. iberica seed germination. The highest level of germination of C. iberica was achieved at fluctuating temperatures of 15/25°C (night/day). The seed germination of C. iberica was stimulated by light and little germination occurred under continuous darkness. The pH solution did not have any effect on its seed germination. Centaurea iberica was tolerant to both salt and water stress. The level of seedling emergence was greatest for the seeds that were located on the soil surface, declining with depth, and no seedling emerged from a soil depth of 4 cm. These results indicated that C. iberica has the potential to infest more fields in the western parts of Iran, particularly rainfed areas. Based on the results of this study, crops with a dense canopy and/or planted in narrow‐row intervals could be used to diminish the seed germination of C iberica. In addition, the adoption of tillage systems that bury the seeds of C. iberica under the 4 cm depth would effective in its management.