摘要
迎红杜鹃 ( Rhododendron mucronulatum Turcz.)的成熟花粉为二细胞型 ,精细胞在花粉管中形成。花粉管中的两个精细胞及与营养核之间互相联结 ,形成雄性生殖单位。两个精细胞的细胞质中均含有丰富的细胞器 ,包括质体、线粒体、小泡及微管 ,内质网和高尔基体稀少。具正常结构的精细胞质体在切面上多呈环形或哑铃形 ,内膜不发达 ,基质电子密度高。线粒体为球形或棒状 ,基质电子密度较低。 DNA特异性荧光染色显示 ,生殖细胞及精细胞中均含有大量类核 ( nucleoid) ,两个精细胞中的类核数量无明显差异。结果证明了杜鹃精细胞中存在大量具 DNA的可遗传细胞器 ,为杜鹃属植物的双亲细胞质遗传方式提供了细胞学证据。
The mature pollen grains of Rhododendron mucronulatum Turcz. conform to the 2 celled type. Sperm cells differentiated within the pollen tube about 24 hours after germination in vitro and paired together, one of which being linked with the vegetative nucleus,forming a male germ unit (MGU). Abundance of plastids,mitochondria,microtubules and single membrane bounded vesicles could be visualized in each sperm cell, however,endoplasmic reticulum and Golgi apparatus were scarce. The electron dense plastids with normal structure gave ring like or dumbbell appearance in sections. Mitochondria were smaller and less electron dense in contrast to the plastids. DNA epifluorescence technique revealed that the generative and sperm cells contained numerous organelle nuclei (nucleoids).There was no difference in nucleoid number between the two sperm cells in a pollen tube. The results confirmed the possible existance of cytoplasmic inheritance potential of the male gametes of Rhododendron.
基金
国家自然科学基金资助课题
高等学校博士点专项科研基金
关键词
杜鹃
精细胞
超微结构
DNA荧光
细胞质遗传
Sperm cell
Ultrastructure
DNA epifluorescence
Cytoplasmic inheritance
Rhododendron mucronulatum
