中文摘要：

半日花（Helianthemum soongoricum）属强旱生植物,其组织富含多糖和多酚等次生代谢物质,采用常规CTAB和SDS等方法提取的半日花基因组DNA由于含有多糖等杂质,无法进行PCR扩增和限制性酶切等试验,为此,在CTAB法的基础上进行了改进.第1步通过向植物组织CTAB提取液中添加高盐和乙醇来沉淀部分多糖,第2步将获得的DNA粗提液,经过CTAB分离溶液沉淀、NaC1溶解、乙醇沉淀等方法,可有效去除半日花组织中的残余多糖等杂质,提取DNA的质量和纯度经凝胶电泳条带清晰、无降解、无多糖等杂质.PCR扩增和限制性内切酶的结果表明,通过改进的方法所获得的DNA,可以进行PCR扩增试验,扩增条带清晰,基因组DNA能被限制性内切酶完全酶切,该方法为后续半日花分子生物学研究奠定了重要基础.

英文摘要：

Helianthemum soongoricum is a strong xerophils with rich secondary metabolites material including polysaccharide, polyphenol and pectin etc..It is difficult to obtain the genomic DNA for next molecular experiments using the traditional methods i.e. CTAB and SDS. In this paper, a modified extracting genomic DNA method based on the classical CTAB method were carried out, which can remove polysaccharide, polyphenols and pectin effectively through added 5 mol-L-1 NaC1 and absolute ethanol in CTAB lysed plant tissue, following the rough DNA solution precipitated by 2%CTAB separating solution and precipitated DNA redissolved by 1 mol＂ L-1 NaC1. Finally, the DNA was precipitated by 95% ethanol. The result showed that the extracted DNA is purified as gel electrophoresis show clear and whole band, indicating there was no significant DNA degradation in the extraction process and eliminating the interference of polysaccharide and polyphenols basically. The DNA obtained can be amplified by PCR, and digested by restriction enzyme EcoR I, which laid an important foundation for subsequent molecular study research on Helianthemum plants.