Study of the Structure of Artichoke (Cynara scolymus L.) Flowers

This study reports the arrangement of the flower head and the structure of the floral organs of the artichoke (Cynara scolymus L.) cultivar 'Bayrampasa', which is a very popular variety in Turkey. The structure of flower of this cultivar was investigated under a stereomicroscope, light microscope, and Scanning Electron Microscope (SEM). Additionally, the flower development stages were examined. The flower heads contain multiple flowers attached to a single receptacle. The flowers on the flower head are arranged in the form of a disc. The maturation of the flowers starts from the outer part of the head and continues towards the center. The number of flowers per head was determined to be 800-1200. The flowers exhibited hermaphroditism, and one flower was found to have five rudimentary petals, five stamens, and one pistil. The ovary was the inferior type. The style was of the closed type and was very long. The stigma was very long and had two portions, with one portion shorter than the other. The stamen had one theca with two lobes. The pollen was lifted up and distributed at the outer sides of the stigma, which is the secondary pollen presentation system. The pollen grains of this cultivar were circular in shape and trizonocolporate. The pollen surface was echinate with spin projections. The pollen grain length was 54.33 mu m and the spin length was 5 mu m in the examined cultivar. The different stages of flower development were seen in the flower head. The flowers were divided into four different stages of development and they have Measuremented in these stage.