Observation Of Embryo Microstructure And Study On Some Physiological Changes During Early Development Stage Of Aegiceras Corniculatum

Mangroves possess distinctive vivipary. Vivipary is divided into two types:cryptovivipary and exposed vivipary. Aegiceras corniculatum belongs to the type of cryptovivipary .The embryo developmental stages from zygote to the seedling(hypocotyle) have been studied on the vivipary mangrove. But the early stage before zygote of cryptovivipary and exposed vivipary is still to be investigated.Megasporegenesis and microsporegenesis, male and female gametophyte of Aegiceras corniculatum had observed in this paper,and the results as follows:1.Sporegenesis and the development of female and male gamepothytes in Aegiceras corniculatum are studied by the means of paraffin wax.the main results are as follows:(1) The wall of anther consists of four layers:epidermis,endothecium, middlelayers and tapetum from out to inside.Tapetum cell is of secretory type.(2) Cytokinesis of micro- sporocyte meioticdivision is of simultaneous type. Tetrasporophyte is tetrahedral (3) Mature pollen grain is of 2-cell type. And of four germ pores (4).The ovule is double integuments,tenuinucellate.Megasporocyte meiotic divides into T-type four megaspores .The megaspore near chalazae is the functional one.Embryo sac is of Polygonum type.These results integrated the dada of vivipary.2,The embryo development of Aegiceras corniculatum occurred with these characters: the epidermis didn't decompose when the anther matured, endothecium and middlelayers'wall thickened in the latter developmental stages. there are groups of tanni-cells in the wall of anther,and there are secretory structures like the salt gland in the ovarys(this had not reported in other plant).all of these structures may related with the adaptations of environment.3,We observed that the suspensor can elongate during the embyo...