大麦染色体银带的研究

Studies on Chromosome Ag-banding in Hordeum Vulgare

本文以六棱、四棱和二棱大麦为材料,用去壁低渗火焰干燥法制备染色体标本,标本在60℃恒温下经70—80％AgNO_3水溶液处理12—14小时,可在核仁组成区、着丝粒和端粒出现黑色银染区。细胞化学反应说明这些不同区域的银染物质具有相同的性质。银染带型与C带型和N带型迥然不同,3种大麦的银染带型也有差别。试验还证明染色体标本制备技术对银染效果影响极大,只有合适的酶解和火焰干燥处理才能促使着丝粒和端粒显示出银染正反应。

Three varieties of barley were selected for Ag-staining. Prepared by an enzyme digestion-hypotonic treatment-flame drying procedure, the chromosomes were treated with 70-80% AgNO3 at 60℃ for 12-24 hours, then black Ag-stained regions appeared at nucleolus organizer regions (NORs), centromeres and telomeres. It was cytotihernincally demonstrated that those Ag-stained regions are of the same nature. The patterns of Ag-banding were distinct from those of C-and N-bands, the Ag-banding patterns were also different among the three varieties. Ag-staining was proved to be strongly affected by chromosome preparation. Both enzyme digestionand flame drying were important factors for centromeres and telomeres to show positive Ag-staining reactions.