摘要
穗花杉(Amentotaxus argotaenia(Hance)Pilger)为国家三级重点保护的珍稀濒危植物,雌雄异株。根尖细胞染色体分析表明:雌株和雄株的染色体数目为2n=40,其中第1对和第2对为中部着丝粒染色体,第3—20对为端部着丝粒染色体。核型为2n=40=4m+36T。雌雄株除第2对的长度稍有差异外,其余各对的相对长度和臂比都较近似,可能尚无性染色体分化。Giemsa C带显示,间期核有3个较大的染色中心,最长的3条染色体的中央缢痕有深染色带纹,可能是着丝粒和NOR的复合结构。雌雄株间无明显差异。从染色体数目、随体和次缢痕位置看,穗花杉均不同于红豆杉科其它属和三尖杉科,而接近罗汉松科罗汉松属的某些种。本作者赞同Hance将穗花杉属归于罗汉松科。
Amentotaxus argotaenia (Hance) Pilger is valuable and imminent danger plant and belongs tio the prior protective plant of third class in our county. It is dioecious. Through the chromosomal analysis at the cell of root tip, it is shown as below: the chromosome number in both the female and male plants is found to be 2n = 40. Among them both third to twentieth paris of chromosome are metacentric chromosomes, the third to twentieth paris of chromosome are telochromosomes. The karyootypic formula is 2n = 40 = 4m+36T. Besides there is a little difference of the second pair of chromosome in both the female plant and male plant. The relative length and arm ratio of the other pairs of chromosome all are more approximate. It may not be differentiae in the sex chromosomes.
According to the Giemsa C banding it is shown that the interphase nucleus has three bigger chromocentres. In the middle part of the three longest chromosomes there is a banding widely and darkly stained. It may be compound structure of the centromere and NOR. It is not obviously different in both the female plant and male plant.
From the chromosome number and the place of satellite and secondary constriction, theAmentotaxus argotaenia all differs from other genera of Taxaceae and Cephalotaxaceae. But it is near some species of Podocarpus in the Podocarpaceae. The results made in prasent study will support Hance's concept in that the Amentotaxus argotaenia is belong to the Podocarpaceae.
出处
《云南植物研究》
CSCD
1993年第4期385-391,共7页
Acta Botanica Yunnanica
基金
国家自然科学基金资助项目
关键词
穗花杉
染色体
染色体组型
杉
Ammentotaxus argotaenia
Chromosome
Karyotype
Giemsa C banding
