【摘要】 45 S rDNA和5 S rDNA是砂梨中与核糖体RNA合成有关的2个功能片段.通过双色FISH(fluorescence in situ hybridlzation)确定了45 S rDNA序列和5 S rDNA在砂梨中期染色体上的分布,其中45 S rDNA位于砂梨的第4号,第11号和第15号染色体的短臂末端.5 S rDNA序列位于第12号染色体上着丝粒附近,而在第6和第13号染色体上则分布在长臂上.更多还原

【Abstract】 Pear(Pyrus pyrifolia L.)is a most important fruit in the world.The chromosomes of pear are relatively small in size.45 S rDNA and 5 S rDNA are two functional fragments associated with ribosomal RNA synthesis.In this study,a two-color FISH(fluorescence in situ hybridization)method was employed to investigate their distribution on the metaphase chromosomes of pear.While 45 SrDNAwas detected at the end of the short arms of chromosomes 4,11 and 15,the signals of 5 S rDNA were mapped on the short arm of chromosome 12.close to the centromere region,and on the long arms of chromosome 6 and 13更多还原