Male-sterile plants were obtained from a variety of the Welsh onion (Allium fistulosum) Isikura in 1964. In order to examine the pollen degeneration of the male-sterile individuals, the anthers of the male-sterile and normal plants here fixed in Carnoy´s fluid, sectioned 12μ thick and stained with Heidenhain´s iron-alum haematoxylin.
The results obtained were summarized as follows:
1. The tapetum of the male sterile anther was composed of some what smaller size cells and cytoplasm was supposed thiner, for their light staining with haematoxylin, as compared with the normal fertile one´s.
2. The tapetum of male-sterile plant slightly delayed in stage of cell walls broken down, fusion of nucleus and cytoplasm and formation of so-call periplasmodium phenomena than the normal plant $lt;figs. 1, 8$gt;.
3. Until the microspore´s complete stage from PMC the sterile plant was almost normally developed, but as the blooming stage approaches the microspores stoped their development to give rise sterile pollen grains and we can meet with only single nucleus, while the normal one´s have been observed two nuclei, generative and vegitative.
4. We have no seen the pseudodium-like incursions in anther cavity as in onion of which pollen grain is sterile.
5. The results of the present study indicate that the PMCs in sterile welsh onion grow up normally to microspore stage of which development being sustained with foods stored beforehand they-self and served with some what smaller tapetal cells, as compared with the normal, of which contain nutrition is poor, and that by irregular process. So that finally there may be deficient in foods and nourishing storage to reach normal pollen grains.
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