The morphological and anatomical studies of inflorescence and male flower in Pycnocycla nodiflora Decne. ex Boiss. (Apiaceae)

In this research، morphology and anatomy of male flower structure in Pycnocycla nodiflora Decne. ex Boiss. belonging to family Apiaceae were studied.. Application of some characteristics such as inflorescence، umbel florets and fruits in the classification of members of this family have paved the way for studies focusing on the flower structure. Morphological and cytohistological studies were performed by stereo- and light-microscopy using fixation and sectioning. Some morphological specificities of flower in this species included compound umbel inflorescences composed of 3-5 umbellules، involucre with 5 short and triangular bracts، 7 flowers in an umbellule، swollen peduncle in male flowers، heteromorphous sepals، color combination of white and purple of petals. Ttrichoms were abundantly observed on most flower parts. Anthers were dorsifix and structures with wrinkled edges were seen in the middle of male flower receptacles. Anatomical studies demonstrated the presence of secretory ducts with shizogenous development in sepal and petal structures. Hair formation on the epidermis of these structures was increased during maturation. Middle layer was transient and tapetum was of secretory type. Simultaneous cytokinesis produced tetrahederal tetrads. Anther dehiscence was longitudinal and released pollen grains were dumbbell shape. Some anthers in flower as well as some pollen sacs in an anther developed insimultaneously.