DNA分析是一种有效地鉴别木材的方法，但它要求要从木材中得到足够质量和数量的DNA。因此，本试验以降香黄檀气干材为原料，采用改良的CTAB法、QIAGEN试剂盒法和PTB法分别提取降香黄檀心材和边材部位的DNA，比较从不同部位木材组织中提取DNA的质量差异，以期为从心材和边材组织中提取DNA探寻合适的方法。结果表明，3种方法从边材和心材部位提取DNA浓度范围分别为：75.95～937.38 ng·μL-1，4.46～806.56 ng·μL-1，其中PTB法从边材和心材部位提取的DNA浓度都是最高的，试剂盒法提取的DNA浓度都是最低的。3种方法提取的边材部位DNA经纯化处理后能够满足PCR扩增目的片段的要求；只有PTB法提取的心材部位的DNA经纯化处理后能够满足PCR扩增目的片段的要求。3种方法都能够从边材组织中提取出DNA，PTB法更适合从心材组织中提取DNA。
DNA analysis is an effective method for wood identification. Obtaining sufficient quantity and quality DNA is the prerequisite. In this paper, Dalbergia odorifera T. Chen of Leguminosae sp. family was selected as material. Three methods, i.e., modified CTAB, DNeasy Plant Mini kit (QIAGEN) and PTB (N-phenacylthiazolium bromide) were employed to extract the DNA in sapwood and heartwood. The quality and quantity of the DNA extractions in the two zones were compared to explore the proper methods for extracting DNA in different parts of wood. The results showed that the concentration of DNA in sapwood and in heartwood isolated by the three methods ranged from 75.95-937.38 ng·μL-1, 4.46-806.56 ng·μL-1, respectively. The maximum value of DNA concentration was reached by the PTB method in sapwood and heartwood, meanwhile, the minimum value was reached by the kit method. The target sequence of DNA in sapwood isolated by the three methods was amplified successfully after being purified, while the DNA in heartwood isolated by the PTB method were subjected to polymerase chain reaction after being purified. The DNA in sapwood can be extracted by the three methods, but the DNA in heartwood can be extracted more suitably by the PTB method.