【摘要】 苔藓植物个体微小，为得到一种适于苔藓微量样品使用的DNA提取方案，首先对前人提取植物DNA的方法进行了筛选；其次对所选择的3种适于提取苔藓样品DNA的方法——CTAB法、尿素法和磁珠法进行了改良；最后通过使用上述3种改良方法对牛角藓Cratoneuron filicinum植物样品总DNA进行提取，并比较了提取效果、提取时间和费用.结果显示：3种改良方法均可从2 mg干燥牛角藓材料中提取总DNA并得到阳性PCR结果.其中，改良磁珠法提取的DNA浓度较高，提取过程时间短，但成本高于其他2种方法.改良CTAB法提取的DNA浓度低于磁珠法，且实验耗时长，但DNA纯度较高，且实验成本仅为磁珠法的5%.PCR实验显示改良磁珠法与改良CTAB法的扩增成功率均为100%,而改良尿素法的扩增成功率仅为75%.认为改良磁珠法与改良CTAB法均可作为微量苔藓样品DNA提取的优选方案.更多还原

【Abstract】 Bryophytes are a kind of tiny plant.This study was performed to determine a DNA extraction method suitable for trace bryophyte materials.Firstly, the existing methods of plant DNA extraction were screened.Secondly, the three selected methods of bryophyte DNA extraction, namely CTAB method, urea method, and magnetic bead method, were improved.Finally, the total DNA of moss sample Cratoneuron filicinum was extracted by the above-mentioned three improved methods, and the effect, time, and cost of the three methods were compared.The results showed that the total DNA could be extracted from 2 mg of dried hornwort material by all three improved methods and positive PCR results were obtained.Among them, the modified magnetic bead method had the highest concentration of the extracted DNA and the shortest extraction time, but its cost was higher than that of the other two methods.The concentration of DNA extracted by the modified CTAB method was lower than that of the modified magnetic bead method, and the experiment time was longer, but the highest purity of DNA was obtained by the modified CTAB method, and its experimental cost was only 5 % of that of the modified magnetic bead method.PCR experiments indicated that the success rate of amplification by the modified magnetic bead method and modified CTAB method were both 100 %,whereas the success rate of the modified urea method was only 75 %.The modified magnetic bead method and modified CTAB method provided in this study can be used as the preferred protocols for DNA extraction from trace bryophyte materials.更多还原