小麦-黑麦1BL/1RS易位系中的染色体结构变异

Structural Variation of Chromosomes in Wheat-rye 1BL/1RS Translocation Lines

用黑麦(Secale cereale L.)自交系Kustro与普通小麦(Triticum aestivum L.)品种绵阳11杂交,获得了八倍体小黑麦MK,再用绵阳11与MK回交,用基因组原位杂交(GISH)和荧光原位杂交(FISH)的方法从回交后代中筛选到含1条1BL/1RS易位染色体的植株13FT-100。为了筛选含有变异染色体的姊妹1BL/1RS易位系,用FISH方法对植株13FT-100的自交后代进行了分析。结果表明,在1个后代植株中,1条6B染色体在核仁组织区断裂,造成6BS端部缺失;而在另1个后代植株中,1条1BL/1RS易位染色体的1BL端部Oligo-p Sc119.2-1信号缺失。变异6B染色体可以用来研究6BS臂从核仁组织区到端部区段的功能,变异1BL/1RS易位染色体可以用来研究1BL的变异对1BL/1RS易位染色体发挥功能的影响。本研究结果提示,对于小麦远缘杂交后代,应多留意小麦染色体结构的变化,获得具有新型结构的小麦染色体或易位染色体可能对小麦育种研究更具重要意义。

Octoploid triticale MK was derived from a cross between common wheat T. aestivumL. Mianyang 11 and rye S. cereale L. Kustro. Progeny were obtained by backcrossing MK with Mianyang 11. A plant 13FT-100,which contained a 1BL /1RS translocation chromosome,was detected from these progeny by using genomic in situ hybridization（ GISH） and fluorescence in situ hybridization（ FISH）. To obtain sibling 1BL /1RS translocation lines that contain variant chromosomes,FISH was used to analyze the self-crossing progeny of plant13FT-100. In one descendant of 13FT-100,a 6B chromosome was broken at nucleolus organizer region（NOR） and the segment from NOR to telomere of 6BS arm was deleted. In another descendant,a 1BL/1RS translocation chromosome without signals of Oligo-p Sc119. 2-1 on telomeric region of 1BL arm was detected.The variant 6B chromosome can be used to study the function of the segment from NOR to telomere of 6BS arm and the variant 1BL /1RS chromosome can be used to investigate the influence of changed 1BL on the function of 1BL /1RS translocation chromosome. The results in this study indicated that structural variations of wheat chromosomes can be induced by wide hybridization. More attention should be paid to the structural variations of wheat chromosomes in wide hybrids,which might be more important for wheat breeding program.