摘要
The cytological mechanism of plastid and mitochondrion inheritance in Pinus is an interesting research topic with only a limited number of published articles. The results indicate that the sperms of Pinus tabulaeformis Carr. contain abundant plastids, mitochondria and organelle DNA. These data provide reliable cytological evidence of paternal plastid and mitochondrion inheritance in Pinus . The results are in line with the confirmed general rule of paternal plastid inheritance in Pinaceae. But whether mitochondria in sperm cells can be transmitted into the embryos is an issue needs further developmental studies. Another important finding is that contrary to earlier classification of the male gamete of Pinaceae into the male nuclei type, the results reveal that male gametes in Pinus tabulaeformis are actually cells. However, the sperm cells are only surrounded by plasma membranes without cell walls. The larger leading sperm cell in a pollen tube section is long in shape, with a large amount of cytoplasm; while the second sperm cell is smaller, round in shape and contains less cytoplasm. Whether this feature of the male gamete type could be considered as a representative characteristic of the family is discussed and further conclusions await more experimental evidences from studies on plants from different species.
证明了油松 (PinustabulaeformisCarr.)雄配子存在质体和线粒体及细胞器DNA ,提供了油松具父系质体和线粒体遗传基础的确切的细胞学证据 ,结果与松科植物在遗传学上已确定的父系质体遗传的一般规律是一致的。但精细胞中的线粒体是否能传递至胚 ,还需要追踪其后的发育过程。另一重要的结果是揭示了油松的雄配子是细胞 ,这与以前将松科植物雄配子归入雄核 (精核 )的类型不同。精细胞无壁 ,仅被质膜包围。在切面上 ,第一精细胞体积大 ,长形 ,具大量的细胞质 ;第二精细胞体积较小 ,球形 ,细胞质量少。根据油松雄配子是细胞的类型 ,对松科植物雄配子是细胞还是雄核进行了讨论 ,提出了雄配子的类型是否能代表科的特征 。
基金
TheNationalNaturalScienceFoundationofChina!( 3 9670 0 94)
