Testing a hypothesis of intergeneric allopolyploidy in vine cacti (Cactaceae: Hylocereeae)

Olofron Plume, Shannon C.K. Straub, Noemi Tel-Zur, Aroldo Cisneros, Bert Schneider, Jeff J. Doyle

Research output: Contribution to journalArticlepeer-review

16 Scopus citations

Abstract

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 these vine cacti, and two (phyC and Vatp1) were sampled from H. megalanthus and a subset of Hylocereus and Selenicereus species. In both cases, H. megalanthus haplotypes were more closely related to each other than to other Hylocereus or Selenicereus haplotypes. Thus, we found no evidence for allopolyploidy, let alone intergeneric allopolyploidy, in H. megalanthus.

Original languageEnglish
Pages (from-to)737-751
Number of pages15
JournalSystematic Botany
Volume38
Issue number3
DOIs
StatePublished - 21 Oct 2013

Keywords

  • Chloroplast sequences
  • Hylocereus
  • Selenicereus
  • dragon fruit
  • low-copy nuclear genes
  • nrDNA ITS
  • pitahaya

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Genetics
  • Plant Science

Fingerprint

Dive into the research topics of 'Testing a hypothesis of intergeneric allopolyploidy in vine cacti (Cactaceae: Hylocereeae)'. Together they form a unique fingerprint.

Cite this