Subgenome analysis of two southern hemisphere allotriploid species in Sphagnum (Sphagnaceae). (September 2014)

• Record Type: Journal Article
• Authors: Karlin, Eric F.
• Is Part Of: Journal of bryology. Volume 36:Part 3(2014)
• Page Start: 165
• Page End: 179
• Publication Date: 2014-09
• Subjects: Bryology -- Periodicals; Bryophytes -- Periodicals; Bryology -- Great Britain -- Periodicals; Bryophytes -- Great Britain -- Periodicals; 588
• DOI: 10.1179/1743282014Y.0000000098
• Languages: English
• ISSNs: 0373-6687

Abstract

<abstract> <title> <x content-type="archive" xml:space="preserve">Abstract</x> </title> <p> <italic>Sphagnum</italic> ×<italic>australe s.l.</italic> and <italic>S.</italic> ×<italic>falcatulum s.l.</italic> are both cryptic species complexes of gametophytically allodiploid and allotriploid cytotypes, with the allodiploid cytotype being one parent of the respective allotriploid cytotype. Phylogenetic analyses of <italic>S.</italic> ×<italic>australe s.l.</italic> and <italic>S</italic>. ×<italic>falcatulum s.l.</italic> were undertaken using sequences from two plastid loci and cloned sequences from three nuclear loci. Subgenomes from three subgenera were detected in allotriploid <italic>S.</italic> ×<italic>australe</italic>. The haploid parent of allotriploid <italic>S.</italic> ×<italic>australe</italic> was <italic>S. fimbriatum</italic> (subg. <italic>Acutifolia</italic>). One of the two subgenomes contributed by allodiploid <italic>S. australe</italic> was associated with <italic>S. strictum</italic> (subg. <italic>Rigida</italic>); the parental species associated with the other subgenome could not be identified, either at the species level or in terms of subgenus association. It may represent an early diverging lineage of subg. <italic>Sphagnum</italic> or a previously undetected subgenus. Allotriploid <italic>S</italic>. ×<italic>falcatulum</italic> has subgenomes from two subgenera. This study confirms prior findings that <italic>S. cuspidatum</italic> (subg. <italic>Cuspidata</italic>) was the haploid parent of allotriploid <italic>S.</italic> ×<italic>falcatulum</italic>. One of the two subgenomes contributed by allodiploid <italic>S</italic>. ×<italic>falcatulum</italic> was associated with subg. <italic>Cuspidata</italic> (species unidentified) and the second was associated with subg. <italic>Subsecunda</italic> (species unidentified). Recurrent allopolyploidy appears to have been associated with the complex evolutionary processes (inter-subgeneric hybridization, interploidal hybridization, double allopolyploidy) which resulted in each of these two allotriploids. The highest level of divergence detected among the subgenomes in each of these <italic>Sphagnum</italic> allotriploids is comparable to the average genetic divergence reported for angiosperm allopolyploids.</p> </abstract>