关键词: 菊花, 托桂花型, 花发育, 组织结构

Abstract: We observed the floral development of anemone and non-anemone type chrysanthemum as well as the histological structures of different types of petals by paraffin section method. The results indicated that the flower bud differentiation of chrysanthemum included two stages such as the inflorescence and floret differentiation. The difference of floral development between anemone and non-anemone type chrysanthemum occurred in the stage of the elongation of floret corolla. The histological structure of disk floret in the anemone type chrysanthemum plays similarities with that of the ray floret not only at their developmental stage but also at the mature stage. They all consist of multiple cell layers including upper and lower epidermal cell layers and internal loose mesophyll cells. Nevertheless，the disk floret of the non-anemone type chrysanthemum just has the petal layout of upper and lower epidermal cell layers. In the development of the disk floret in anemone type chrysanthemum，the exuberant division activity of the internal cells of the petal and the well developed vascular tissues are probably the important reasons for the formation of the anemone.

Key words: chrysanthemum, anemone type, floral development, histological structure