Morphological Variation in Achenes in Certain Species Belonging to the Tribe Cardueae (Asteraceae) in Iraq

Abstract

This study investigated the morphological attributes of achenes among nine species within the Cardueae tribe of the Asteraceae family in Iraq. The specimen collection occurred between March 2021 and July 2022. Dissecting microscopy was used to document twelve morphological characteristics. Among the traits that were evaluated, it was found that achene size, symmetry, hilum location, the achene apex, and the existence or lack of the pappus were crucial diagnostic markers for identifying the species. The results demonstrate the significance of several achene traits, including color, size, and hilum, in recognizing and separating the studied species. Furthermore, the shape of the achene assisted in distinguishing Notobasis syriaca from the different species under investigation. The prognosis of the species was significantly influenced by the color and the outer and inner pappus lengths. The achene apex shape was crucial in dividing the studied species into two groups: denticulate and entire.