Embryology of the lady%26apos;s slipper orchid, Paphiopedilum delenatii: Ovule development

作者：Lee Yung I^*; Yeung Edward C

来源：Botanical Studies, 2012, 53(1): 97-104.

• Callose
• Embryology
• Lady%26apos
• s slipper orchid
• Nile red
• Ovule

Paphiopedilum delenatii is an endangered slipper orchid with delicate flowers that is native to Vietnam. An understanding of this plant species%26apos; reproductive biology is required for its effective propagation and conservation. P delenatii has a bisporic pattern of embryo sac development with a six-celled number in a mature embryo sac. Prior to pollination, the nucellar filaments are present within the ovary. The archesporial cell at the tip of the nucellar filament differentiates into a megasporocyte fifteen days after pollination. As the megasporocyte matures, the nucleus becomes located at the micropylar end of the cell, resulting in an uneven distribution of the cytoplasm with the starch granules becoming more abundant at the chalazal end. After the first meiotic division, a distinct callose layer separates the micropylar dyad from the chalazal one. Soon after, a callose wall completely encloses the functional dyad at the chalazal end. As the functional dyad increases its size, the callose remains in the common wall separating the two dyads as well as in the chalazal end wall of the functional dyad. One notable finding of this study is the presence of cuticular material in the lateral walls of the mature embryo sac. The deposition of the cuticular material may serve to strengthen the fairly large embryo sac and helps to conserve water for the developing embryo after fertilization.

• 出版日期2012-1