Testing a Hypothesis of Intergeneric Allopolyploidy in Vine Cacti (Cactaceae: Hylocereeae)

Autor: Jeff J. Doyle, Olofron Plume, Shannon C. K. Straub, Noemi Tel-Zur, Aroldo Cisneros, Bert Schneider
Rok vydání: 2013
Předmět:
Zdroj: Systematic Botany. 38:737-751
ISSN: 1548-2324
0363-6445
DOI: 10.1600/036364413x670421
Popis: Allopolyploidy is common in angiosperms, but only rarely involves different genera. One hypothesized case of intergeneric allopolyploidy is Hylocereus megalanthus, a member of Cactaceae tribe Hylocereeae, a group of vine cactus species, some of which are known for their edible fruits (“pitahaya” or “dragon fruit”). This polyploid species has been interpreted as morphologically intermediate between Hylocereus and Selenicereus. Plastid and nuclear ribosomal DNA ITS sequences from all H. megalanthus individuals sampled are either identical (plastid), or form a monophyletic clade despite considerable intraindividual polymorphism (ITS). Plastid and ITS phylogenies both show H. megalanthus nested within a well-supported Hylocereus, which in turn is nested within a paraphyletic Selenicereus. The absence of more than one lineage of ITS in H. megalanthus is consistent with autopolyploidy, but could be due to inter-homoeologue concerted evolution. Numerous low-copy nuclear genes were tested for utility in ...
Databáze: OpenAIRE