杉木根尖细胞染色体C带及荧光带型的研究

C Banding and Fluorescent Banding Pattern of the Chromosomes of Cunninghamia lanceolate

对杉木的根尖有丝分裂中期染色体进行研究,结果发现,杉木的染色体核型为2n=22=20m(2SAT)+2sm,10对染色体均为中间着丝粒染色体,只有1对(最小一对)为近中着丝粒染色体,第3对为具随体的染色体,核型不对称性属于1B型。对杉木的GiemsaC-带进行研究发现,有8对染色体有C带出现,只有3对染色体无C带,C带纹均出现在染色体的两臂。且利用C带在杉木11对染色体上的分布情况,能够较容易地辨认出11对中的5对染色体。而荧光分带研究的结果则为在杉木根尖细胞的中期分裂相中,只有CMA(色霉素A3)在带有随体的染色体的次缢痕和随体处有专一的荧光带纹,而DAPI无带。CMA带比DAPI带更适宜杉木的分带研究。最后讨论了C带与荧光带的在杉木染色体研究中的应用。

The chromosome karyotype, C-banding, and fluorescent banding of Cunninghamia lanceolate （Chinese fir） were analyzed in this paper, The results were as follows： The karyotype of metaphase chromosome is 2n=22=20m （2SAT）＋2sm, 10 pairs of chromosomes are medium centromeric chromosomes and 1 pair of chromosome is submedium centromeric chromosome. And there is 1 pair of satellites occurred on chromosome 3. Karyogramwas belong to the type of 1B. The C -banding occurred on 8 pairs of chromosomes, but it didn＇t occurred on 3 pairs of chromosomes. All of C banding is intercary-banding. And 5 of the 11 chromosomes of Chinese fir were easily identified by C banding. CMA banding only occurred on the chromosome with satellites, All of chromosome without DAPI-band, CMA banding is more suitable for the fluorescent banding of Chinese fir than DAPI, Fluorescent banding can be detected in the chromosomes by using CMA, but no banding by DAPI. At last we also discussed that how to apply the understanding of C- banding and fluorescent banding pattern in the field of chromosome studies of Cunninghamia lanceolate.