【摘要】 为了了解5S rDNA和45S rDNA在斑茅染色体上的分布情况及其染色体基数,利用荧光原位杂交技术在斑茅海南92-77(2n=60)和海南92-105(2n=60)的中期染色体和间期细胞核上进行5S rDNA和45S rDNA定位研究。结果表明在海南92-77和海南92-105的中期染色体和间期细胞核上45S rDNA位点均有6个信号位点,且均位于染色体短臂的端部上;这6个45S rDNA位点大小具有明显的差异,说明斑茅的45S rDNA的拷贝数存在差异。5S rDNA位点在海南92-77和海南92-105均有6个信号位点,且均位于染色体长臂的着丝粒附近;5S rDNA位点大小相差无几,说明斑茅的5S rDNA的拷贝数差异不大。因此,可以推断染色体数目为60的斑茅染色体基数为x=10。更多还原

【Abstract】 In order to know the physical mapping of 5 S rDNA and 45 S rDNA on the chromosomes of E. arundinaceus and determination of basic chromosome number, the E. arundinaceus chromosome localization of 5 S rDNA and 45 S rDNA was studied by fluorescence in situ hybridization on metaphase chromosomes in Hainan 92-77(2 n=60) and Hainan 92-105(2 n=60). The results showed that the number of 45 S rDNA site signal loci were six at somatic chromosomes of metaphase and cell nucleus of interphase in both Hainan 92-77 and Hainan 92-105, and the signal loci of 45 S rDNA was located in the short arm end of six chromosomes. Among them, loci were different, suggesting that the copy number of 45 S rDNA was different. The number of 5 S rDNA site signal loci were six in both Hainan 92-77 and Hainan 92-105, and the signal loci of 45 S rDNA was located near the long arm of chromosome centromere, all the 6 loci were of similar size, suggesting that the copy number of 5 S rDNA was similar. Therefore, the basic chromosome number of E. arundinaceus with 2 n=60 was determined as x=10.更多还原