MICROSPOROGENESIS, MEGASPOROGENESIS AND THE DEVELOPMENT OF MALE AND FEMALE GAMETOPHYTE IN ALLIUM CHINENSE G.DON

The meiosis during microsporogenesis in four cultivars of Allium chinense G.Don was nearly normal. The arrangement of the microspores in tetrad was isobilateral or tetrahedra. Part of the uninucleate pollens disrupted. When the pollens were released from the loculi,most of them were hollow and had no germ furrow while the others were uninucleated or binucleated. Only a few of them had vegetable nuclei and generative unclei. In addition, pollen had low viability or had no viability, they did not grow pollen tube. The megasporogenesis was the Allium type. Part of the megaspores could form normal 4 nucleate embryo sac. Most of the megaspores developed abnormally,binucleate to 5 nucleate embryo sac were observed. No normal mature megasporogium formed. The reason of the sterility was the abnormality of microsporogenesis and megasporogenesis.