Studies on the Development of Polyad Grains of Calliandra haematocephla Hassk. with Electron Microscopic Technique

陳幼崳(Yow-Yuh Chen)

《TAIWANIA》 18卷1期 (1973/06) Pp. 18-28

https://doi.org/10.6165/tai.1973.18.18

並列摘要

Development of polyad grain of Calliaudra haematocephala Hassk. was studied. Electron microscopy technique preparation was adapted for this study. That is, pre-fix in glutaraldehyde, post-fix in osmium tetraoxide, dehydrate in acetone, embed in plastics, cut with ultramicrotone, thick section (1μ thick) stained with methylene blue-azure II, examine under light microscope, Different developmental stages, namely, undifferentiated, one-, two-, four-, five-, six-, and eight-celled stages were revealed. Each nuclear division is followed immediately by cytokinensis which is common in Monocotyledons and also found in this species. Sporopollenin starts adding on the surface when 4-celled stage is reached (wall formation). Although cell plate has already separated two daughter cells away but sporopolleninous wall had not appeared a t that time. Longitudinally, there can be several octads formed from each locule, however, horizontally there is only on e expected a t the same level. In other words, there was only one pollen mother cell existing at the initiation stag Accompanying events, such as tapetal layer (development and disintegration), and reinforcement of endothecial cells are also reported.