Cell Biological Studies On The Female Sterility Of Clone 28 Of Pinus Tabulaeformis Carr.

The female sterility of plants appears when the development of female organs of plant meet obstacles. The phenomenon of female sterility is common in plant. Pinus tabulaeformis Carr is one of the most valuable species in China, and it is of theoretical importance to study the female sterility of Pinus tabulaeformis Carr.In the seed orchard of Pinus tabulaeformis Carr in Xingcheng, Liaoning Province, the female cones of clone 28 can aggrandize normally, but their ovules stopped growing in the early stage. Cross-pollination experiment indicated that microspores of this clone is normal, and its ovule abortion came from the female sterility.In this dissertation, through anatomic observation and 2-D electrophoresis analysis of protein, the reason and the time of female sterility of clone 28 was studied. And normal clone 14 was chosen as a comparison. It would make a theoretical foundation for further study of female sterility of Pinus tabulaeformis in molecular biology.Through cytological observation on the development of one-year-old macrosporangiates of two clones, it was found that no apparent differences were observed in such stages as the differentiation of macrosporangiate primordium, bract primordium, ovuliferous scale primordium and ovule. So was in the critical stages such as the appearance of macrosporal mother cell, the meosis of macrosporal mother cell and the mitosis of functioning macrospore. Through ultrastructural observation on the nucellus cell of two clones before the meosis of macrosporal mother cell, it was found that the cytoplasm of nucellus cell of clone 28 atrophied and orgalleras were lesser than that of clone 14. This phenomenon was probably correlated with ovule abortion.In early April of second year, the free nuclei in the female gametophyte of clone 14 could continuemitosis, but those of clone 28 could not continue, and disappeared finally. This gave rise to the abortionof ovules of clone 28. The ovules of clone 28 aborted completely in late May.Through 2-D electrophoresis analysis of protein of two-year-old ovules of two clones when the mitosis of free nuclei of clone 28 stopped, it was found that the protein A(19.9kD) is not expressed in clone 28, protein A might be correlated with mitosis of free nuclei. The protein analysis of macrosporangiates of two clones was carried out in the same way before the miosis of macrosporal mother cell, it was found that the protein B(19.0kD) was not expressed in clone 28, and the lack of protein B was probably correlated with the phenomenon that the cytoplasm of nucellus cell of clone 28 atrophied and orgalleras were lesser. Further study on protein A and B is to be probed into.