中文摘要：

目的：克隆芽变毛白杨生根相关基因片段。方法：采用诱导生根和抑制生根两种处理，分别提取芽变毛白杨（Mutant Populus tomentosa）皮部RNA，进行逆转录和差异显示，筛选和克隆特异片段。结果：研究表明不同处理基因表达有一定差别。经Northern鉴定，诱导生根处理的扩增产物中有一条与生根相关的差异片段。将其克隆和测序，该片段编码序列长度316bp。Gen Bank中查询没有发现同源性较高的基因。结论：成功地获得了长度316bp的芽变毛白杨生根相关基因片段，可能为新基因的一部分。该基因片段的获取将为分离全长生根相关基因，查明该基因表达调控的机理提供基础。

英文摘要：

Objective：To obtain the fragment related to roofing gene of mutant Populus tomentosa. Methods： Mutant Populus tomentosa hard branch cuttings was used as the test materials . Total RNA of rooting induced and rooting inhibited cuttings were purified respectively and subjected to different display reverse transcription polymerase chain reaction （DDRT- PCR）, through acrylamids get eleetrophoresis screened specific eDNA fragments. Results： The result showed that different gene expression had been occurred between rooting induced and roofing inhibited. One differential band,which fi＇agment length was 316bp, specific expressed in the rooting induced was detected by Northem blot. It was cloned and sequenced. After searching in Gen Bank, there were no similar sequences reported. Conclusion： The 316bp fragment related to roofing gene of mutant Populus tomentosa was obtained. It will help to isolate full length related to rooting gene and further studies it possible role during root formation.