Abstract:
:The utility of the PCR-based AFLP technique (polymerase chain reaction; amplified fragment length polymorphisms) was explored in elucidating details of polyploid evolution in the Eurasian orchid genus Dactylorhiza. We emphasized Swedish taxa but also included some material from the British Isles and elsewhere in Europe. Three different sets of primers, amplifying different subsets of restriction fragments, independently revealed similar patterns for relationships among the Dactylorhiza samples investigated. The AFLP data support the general picture of polyploid evolution in Dactylorhiza, i.e., that allotetraploid derivatives have arisen repeatedly as a result of hybridization beween the two parental groups D. incarnata s.l. (sensu lato; diploid marsh orchids) and the D. maculata group (spotted orchids). Within the incarnata s.l. group, morphologically defined varieties were interdigitated. The D. maculata group consisted of two distinct subgroups, one containing autotetraploid D. maculata subsp. maculata and the other containing diploid D. maculata subsp. fuchsii. Allotetraploids showed a high degree of additivity for the putative parental genomes, and relationships among them were partly correlated to morphologically based entities, but also to geographic distribution. Thus, allotetraploid taxa from the British Isles clustered together, rather than with morphologically similar plants from other areas.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Hedrén M,Fay MF,Chase MWsubject
Has Abstractpub_date
2001-10-01 00:00:00pages
1868-80issue
10eissn
0002-9122issn
1537-2197pii
88/10/1868journal_volume
88pub_type
杂志文章abstract::Inferring basal relationships among vascular plants poses a major challenge to plant systematists. The divergence events that describe these relationships occurred long ago and considerable homoplasy has since accrued for both molecular and morphological characters. A potential solution is to examine phylogenetic anal...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-10-01 00:00:00
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doi:
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更新日期:2000-05-01 00:00:00
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更新日期:1997-12-01 00:00:00
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