一株具有特异AFLP指纹图谱的杜仲古树

Discovery of an Originally Wild Tree of Eucommia ulmoides Oliver by AFLP Fingerprinting

杜仲（Eucommia ulmoides Oliver）是原产于我国的传统药用植物，虽然目前杜仲被广泛栽培，但野生杜仲已非常稀少，几乎难以见到。作者在利用AFLP分子标记技术研究杜仲的遗传多样性和居群遗传结构时，发现一株采自神农架自然保护区的树龄200多年的雄性杜仲古树（编号为SNJ5）的AFLP指纹图谱与其它582株树龄为10～52年的栽培杜仲的指纹图谱有显著的不同。在总计为191条多态带中，有44条为高频率显性等位基因带（high frequency dominant allele bands，HFDAB，即583个个体中只有1～3个个体缺乏的带）。SNJ5缺乏23条HFDAB，其中有12条HFDAB是SNJ5单独缺乏的，与其他582个个体差异显著（P〈0．05）；另外，SNJ5还具有一条特有带（E＋ACG／M＋CTG引物组合的217bp带）。据此推测这一杜仲古树是原始野生植株，是近年来众多学者认为野生杜仲灭绝后发现的非常重要的种质资源，应加以大力保护。

Eucommia ulmoides Oliver is a traditional medicinal plant species endemic to China. At present, although it is widely cultivated, wild E. ulmoides is extremely rare and in brink of extinction. During our recently extensive molecular investigation in genetic diversity and population structure of E. ulmo/des using AFLPs, a male plant over 200 years old （ Sample code： SNJ5 ） in Shennongjia National Nature Reserve was found to have a unique AFLP fingerprint which was significantly different from that of other 582 cultivated individuals of 10 -52 years old. Of the total 191 polymorphic bands, 44 bands were high frequency dominant allele bands （HFDAB, the bands that were absent only in 1 -3 individuals of the total 583 samples）. SNJ5 was lack of 23 HFDABs in which 12 HFDABs were absent in SNJ5 only. It was significantly different from that of other 582 cultivated individuals （p 〈 0.05 ）. Furthermore, SNJ5 had a private band （217 bp band in E ＋ ACG/M ＋ CTG primer combination）. We suspect that this old E. ulmohtes tree is likely to be the originally wild survivor. An immediate protection action is needed to secure this very important germplasm resource.