应用光学显微镜和扫描电子显微镜,以鹅掌楸〔Liriodendron chinense (Hemsl.)Sarg.〕、北美鹅掌楸(L. tulipifera L.)及杂种鹅掌楸(L. chinense×L. tulipifera)为对照,对重庆酉阳鹅掌楸(Liriodendron sp.)种源‘优酉’(‘Youyou’)的外部形态特征、叶表皮微形态结构特征和花粉形态特征进行观察比较,并利用RAPD标记技术对‘优酉’的遗传关系进行了分析。结果表明,鹅掌楸属各树种在外部形态上存在差别,但在叶表皮和花粉形态特征上表现出明显的一致性,‘优酉’的各形态特征与鹅掌楸有较多相似性。RAPD标记分析结果表明,‘优酉’的遗传距离与鹅掌楸和北美鹅掌楸较远,但与鹅掌楸的遗传关系相对较近。推测‘优酉’可能是由较原始的鹅掌楸向较进化的北美鹅掌楸过渡的1个中间类型。‘优酉’生长速度快、观赏价值高,可直接用于园林绿化及林木种植。

 Using LM and SEM, the external morphological characters, micro-morphological structure of leaf epidermis and pollen morphological features of`Youyou'  (Liriodendron sp.)from Youyang of Chongqing were observed and compared with L. chinense (Hemsl.) Sarg., L. tulipifera L. and L. chinense×L .tulipifera .And the genetic relationship of `Youyou' was analyzed by RAPD markert echnology. The results show that the external morphological structure has some differences among the germplasm resources of Liriodendron  L., but the leaf epidermis structure and pollen morphological features are obviously identical.`Youyou' is more similar to L. chinense in all morphological characters. The RAPD analysis result suggests that `Youyou' is farther from L. chinense and L. tulipifera, while the genetic relationship between `Youyou'  and L. chinense is relatively closer. It is concluded that `Youyou' may be an intermediate type evolving from more primitive species of L. chinense to more evoluational species of L. tulipifera. And `Youyou' can be applied in gardening and forest industry for its fast growing speed and high ornamental value.