Cytotaxonomic study of genusHymenasplenium (Aspleniaceae) in Xishuangbanna, Southwestern China |
| |
Authors: | Xiao Cheng Noriaki Murakami |
| |
Institution: | (1) Kunming Institute of Botany, Academia Sinica, 650204 Kunming, China;(2) Department of Botany, Graduate School of Science, Kyoto University, 606-8502 Kyoto, Japan |
| |
Abstract: | The gametic chromosome numbers of sevenHymenasplenium (Aspleniaceae) species from Xishuangbanna, Yunnan Prov., China, were investigated. All the examined individuals ofH. obscurum, H. cheilosorum andH. latipinnum were sexual diploids with n=39 chromosomes. Intraspecific cytological variation was found inH. excisum, which has a sexual diploid (n=39) and a tetraploid (n=78). Only a triploid apogamous cytotype (n=ca.117) was found inH. laterepens. Hymenasplenium apogamum showed the most complicated intraspecific variation and included a sexual diploid (n=39), a sexual tetraploid (n=78) and
an apogamous triploid (n=ca.117). This work reports for the first time the sexual diploids ofH. cheilosorum andH. apogamum, which are only apogamous elsewhere in east Asia, Himalayas and Indochina. These results may indicate that this area is one
of the diversity centers ofHymenasplenium. Most of the above species have chromosome numbers based on x=39. In contrast,H. costarisorum contains a sexual diploid (n=36) and a sexual tetraploid (n=72), indicating that its basic number is x=36. |
| |
Keywords: | Apogamy Aspleniaceae Chromosome number Cytotaxonomy Hymenasplenium Yunnan Province |
本文献已被 SpringerLink 等数据库收录! |
|