白肉火龙果染色体制片技术及核型分析

Chromosome preparation technique and karyotype analysis of white pitaya (Hylocereus undatus)

摘要: 以白肉火龙果的实生根为制片材料，在去壁低渗法的基础上改进染色体制片技术，并进行核型分析。结果表明，以白肉火龙果种子在粗砂砾中萌发的实生根为材料，以等体积的 0.2%秋水仙素与 0.002 mol/L8-羟基喹啉预处理 1h，在 1 mol/L HCl 中 60益下解离 13 min，制片效果最好。核型分析显示白肉火龙果的染色体数目为 2n=2x=22，全部染色体都为中部染色体，核型公式为 2n=2x=22=22m；染色体的相对长度变化范围为6.95豫-12.97豫，核型为 1A 型，核不对称系数为 52.67%。

Abstract: Real root tips of white pitaya (Hylocereus undatus) as material, the chromosome preparation skill was improved by the wall digestion hypotonic method and the karyotype was analyzed. The results showed that the optimum chromosome preparation was achieved with root from the germination of seeds on coarse gravels, pretreated by the mixture of 0.2% colchicine and 0.002 mol/L 8-hydroxyquinoline for 1 h, and dissociated by 1 mol/L HCl for 13 min at 60%. The chromosome number of white pitaya is 2n =2x =22. The 22 chromosomes are all middle chromosome, so that the karyotype formula of white pitaya is 2n=2x=22=22m, belonging to 1A karyotype. The range of chromosome relative length is from 6.95%to 12.97%and the karyotype asymmetrical coefficient is 52.67%.