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作 者 ：童本群 郝忠颖

期 刊 ：林业科学 1986年 22卷 2期 页码：116-122

关键词：子；

摘 要 ：本文提出一种适用于裸子植物染色体的Giemsa C-带技术。我们发现,迄今能获得染色体分散良好并显示C-带的最佳制备程序有:(1)前处理;(2)固定;(3)离析;(4)压片;(5)气干;(6)5%Ba(OH)₂处理;(7)4X SSC处理;(8)Giemsa染色。所有被研究的三个树种,即杉木、落叶松和樟子松,在间期和中期的染色体都清晰地显示C-带。根据着丝点带、中间带和端部带的数量和分布,这三个种可以在种系发生上彼此区分。它们的C-带简式概括如下: 杉木:2n=22=10(O/P)+10(P/O)+2(PT/O) 落叶松:2n=24=8(O/P)+10(P/O)+2(I/P)+2(P/I)+2(P/P) 樟子松:2n=24=8(O/P)+4(P/O)+4(O/PI)+4(PI/O)+4(P/I) 本文所描述的改良程序对于准确鉴定中期染色体提供了一种高度可重复性的C-带技术,并就有关染色体C-带的分带条件和异染色质显示带纹的本质等问题进行了讨论。

Abstract:An advanced Giemsa C-banding technique for the chromosomes of gymnospermous plants has been developed by modifying the method of the conventional Giemsa C-banding. It was found that the best procedure so far obtained to separat C-banded chromosomes well was: (1) pretreatment; (2) fixation; (3) maceration; (4) squashing; (5) air drying; (6) treatment with 5% barium hydroxides; (7) treatment with 4X SSC and (8) Giemsa staining. All three species stutied i. e. Cunninghamia lanceolata, Larix gmelini and Pinus sylvestris var. mongolica showed clear C-banding in the interphase and metaphase chromosomes. the three species were found to be different from each other phylogen-etically in respects of the number and occurrence of the pericentromeric, intercalary and telomeric (satellite) C-bands. The idiograms of their C-bands were summarized as follows:C. lanceolata: 2n=22=10(O/P)+10(P/O)+2((PT)/O)L. gmelini: 2n=24=8(O/P)+10(P/O)+2(I/P)+2(P/I)+2(P/P)P. sylvestris var. mongolica: 2n=24=8(O/P)+4(P/O)+4(O/(OP))+4(P/I)The procedure described above provides a highly reproducible C-banding technique for distinquishing unequivocally the metaphase chromosomes. The C-banding condition in the chromosomes and the nature of the heterochromatin exhibited were also discussed in the present paper.

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