Meiosis and its stages of pollen mother cells in Chinese white poplar.
Kang Xiangyang;Zhu Zhiti;Zhang Zhiyi.Institute of Populus tomentosa, Beijing For. Univ.,100083, P.R.China.
The meiosis and its stages of pollen mother cells(PMC) of Chinese white poplar( Populus tomentosa Carr.)were studied by the methods of cell genetics in this paper. The results suggested: ① Certain regularity existed in the stages of meiosis of PMC, and the stages were closely correlated with the morphology of inflorescences and the variation of anthers color. ② The behavior of chromosomes during meiosis was different among clones. Univalents in different quantities were found at diakiness and metaphase I, and the separated lagging chromosomes at anaphase I and even at telophases I and II, which indicated the genetic heterogeneity of Chinese white poplar. ③ The occurrence of the multi nucleoli was observed in the stages of meiosis of PMC, with daughter nucleolus containing 8 nucleoli at telophases I and II which merged into one large nucleolus with the development of meiosis. ④ The difference in stages of meiosis existed among Chinese white poplar clones, and even different floral buds in one male tree or different positions in one floral bud showed non synchronization in the meiosis periods of PMC. This suggested extensive population variation in Chinese white poplar.