Genesis of microspore,megaspore and the development of male gametophyte,female gametophyte in Diphylleia sinensis

The microsporogenesis megasporogensis and the formation of male gametophyte and female gametophyte in Diphylleia sinensiswere first reported. The main results can be concluded as follows:anthers are tetrasporangiate and its wall development conforms to the basic type and comprises of epidermis,endothelium,three middle layers and two tapetums at the mature stage from outer to inner. The endothelium develops fibrous thickening and the tapetum was of two cell nuclei mostly,belongs to glandular type. Cytokinesis in the microsporocyte meiosis is of the simultaneous type and the microspore tetrads are mostly tetrahedral and there were still a few other types,such as dilateral,linear,isobilateral and T shape. Circular pollen grains are mainly 2-celled type when shed,occasionally 3-celled type,and had one aperture. Solitary pistil is consisted of only one carpel. Ovary is unilocular. Ovules are amphitropous arrangement on marginal placenta and their development is asynchtonous and crassinucellate with double integument. Micropyle is composing of inner and outer integument. Multi-archesporial comes of the first cell layer under nucellar epidermis. The tetrad of megaspores is linear shaped,with the first cell from the chalazal end being functional. The development of embryo sac belongs to the polygonum type. Three antipodal cells are big and obvious in mature embryo sac,but they are ephemeral.