Independent origins of tetraploid cryptic species in the fern Ceratopteris thalictroides
| Main Authors: | Bayu Adjie, Shigeo Masuyama, Hiroshi Ishikawa, Yasuyuki Watano |
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| Format: | |
| Bahasa: | eng |
| Terbitan: |
, 2007
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| Subjects: | |
| Online Access: |
http://karyatulis.perpustakaankrbali.com//index.php?p=show_detail&id=30 |
Daftar Isi:
- Ceratopteris thalictroides(L.) Brongn is atetraploid fern species that contains at least three cryptic species, the south, the north and the third type.In this study we combined data from both chloroplast DNA (cpDNA) and nuclear DNA sequences of three diploid species and three cryptic species ofC. thalic-troides to unravel the origin of the cryptic species, particularly of the reticulate relationships among the diploid and tetraploid taxa in the genusCeratopteris. Of the three diploid species examined,C. Cornutahad cp DNA identical to that of the tetraploid third type plants, and this diploid species is a possible maternal ancestor of the tetraploid third type. Analysis of the homologue of theArabidopsis thaliana LEAFYgene (CLFY1) identified ten alleles in the genus Ceratop-teris, with six alleles found in C. thalictroides.The un-rooted tree of theCLFY1gene revealed four clusters.Each cryptic species showed fixed heterozygosity at the CLFY1locus and had two alleles from different clus-ters of the CLFY1tree. Consideration of the cpDNA sequences,CLFY1genotypes of the cryptic species and CLFY1gene tree in concert suggested that the cryptic species of C. thalictroideshad originated through independent allopolyploidization events involving C. cornutaand two unknown hypothetical diploid species.