Histochemical Observation of Polysaccharides and Lipids on the Developing Anthers of Michelia figo

Using cytochemical technique,we observed the distribution of polysaccharides and lipids during the anther development of Michelia figo:(1)A few lipids were accumulated in sporogenous cells.At microspore mother cell(MMC)stage,a few lipids were still located in the MMCs which had formed a callose wall.At the same time,a few lipids were accumulated in tapetal cells,but many polysaccharides appeared in other cells of anther wall.After MMC meiosis,tetrad microspores still had a few lipids.(2)After released from tetrad microspores,the free microspores began to accumulate polysaccharides and the number of lipids decreased.At this time,polysaccharides in anther wall cells decreased and endothecium cells enlarged from radial direction.In late microspores,there were still many polysaccharides and a few lipids in the cells.Tapetal cells began to degenerate at this time and many lipids appeared in the cells.(3)In early bicellular pollen,the vacuoles disappeared,and the number of polysaccharides increased evidently.In nearly mature pollen of M.figo,though the lipids had been less,there were still many polysaccharides and some lipids accumulated in the vegetative cells as the storage material of pollen.The study suggested that tapetal cells at microspore mother cell stage contained little number of lipids and no polysaccharides.It appeared that tapetal cells transported nutriment to chamber actively,or transported lipids from middle layer cells without converting to polysaccharides.