Studies On The Embryo And Tissue Dediffrentiate Of Dendroncalamus Sinicus

Dendrocalamus sinicus belongs to Dendrocalamus Nees, Bambusoideae Nees, Gramineae,is the largest bamboo in the world.It belongs large-scale tropical growing thickly bamboos, cangrow to more than 30m tall with 20-30m diameter. It is a multipurpose, especially in timbered utility, valuable, rare and economic species of bamboo, has significant economic value and broad developing prospects. But D.sinicus is few in number because of its narrow distribution. Then it is difficult to live and sprout by traditional planting and can not meet with the needs of seedling. Confronted with this present situation, some studies of theembryogenesis have been done to explain the reason why D.sinicus has only a few seeds, and adopted some tissue culture methods to induce callus from different explants, so as to lay the strong foundation for the genetic transformation.The main results of the overall embryological studies are as follows:(1)The development of D.sinicus stamen is normal. The development of the anther wall structure is normal. There is not any problem no matter in tapetum or in endothecium. From the form of the archesporial cell to the mature of the male gametophyte and in every developing process, no problem can be found. The pollen can be scattered and can germinate,after anther wall began to mature. At the same time,the speed of the pollen's germination is very high and the germinating ration can get up to 92.2% after 30min.(2)The development of the pistil is normal. The growing of pistil analge, ovary, style, integuments and the forming of anatropous ovule are all normal. No problem can be found in archesporial cell, megaspore and the structure and megasporangium. The embryo sac have a normal structure and it has one normal egg apparatus ,one big central cell and many antipodal cells.(3)The time when the stamen mature is not the same as the pistil and D.sinicus is cross-pollinaton. The blooming rhythm of the most flower is the same. D.sinicus can be fertilized normally and can produce normal embryoes, endosperms and seeds, so we can say there is no problem in the fertilization of D.sinicus. It can be said that the reason why D.sinicus has only a few seeds is not because some problems occurred in the fertilization of D.sinicus. No problem has been found in the process which the seeds have grown from eggs.From callus induced from different materials of D.sinicus, we can drawn the main...