中文摘要：

基于火龙果Tyl-copia类反转录转座子的长末端重复序列信息设计引物，采用5因素4水平L16（4^5）的完全随机正交试验，对Mg计浓度、dNTPs浓度、TaqDNA聚合酶用量、引物浓度和DNA含量进行优化，建立火龙果IRAP分子标记反应体系。结果表明，25弘L反应体系含基因组DNA20ng、2．5mmol／LMgCl2、0．10mmol／LdNTPs、10×PCRBuffer2．5μL、TaqDNA聚合酶0．75U、0．25μmol／LLTR引物，0．080g／mL的非变性PAGE胶适于IRAP多态性检测。

英文摘要：

Based on the LTR sequences of dragon fruit （Hylocereus spp. ） Tyl-copia retrotrans- posons, primers for IRAP were designed. The complete random orthogonal design L16 （45 ） was used to optimize the IRAP-PCR system at four levels and five factors, namely, Mg2＋ , dNTP, Taq DNA polymerase, primers and DNA template. The results showed that the optimal system for IRAP amplification was 25 μL mixture containing 20 ng of template DNA,2.5 mmol/L MgCl2,0. 10 mmol/L dNTPs,2.5μL of 10× PCR Buffer,0.75 U of Taq DNA polymerase, 0. 25μmol/LLTR primer. PAGE with 0. 080 g/mL non-denaturing polyacrylamide gel could yield reproducible, clear and reliable bands, which facilitate the identification of dragon fruit germplasms,the elucidation of their genetic diversity as well as assessment of genetic variation.