USF-LVHN SELECT

Phylogenetic relationships of the sweetpotato in Ipomoea series Batatas (Convolvulaceae) based on nuclear beta-amylase gene sequences.

Publication/Presentation Date

3-1-2004

Abstract

Phylogenetic relationships of 13 accessions and a cultivar representing the sweetpotato, Ipomoea batatas (L.) Lam., and its wild progenitors, were investigated using the nucleotide sequence variation of a nuclear-encoded beta-amylase gene. A 1.1-1.3 kb fragment of the gene spanning two exons separated by a long intron was PCR-amplified, cloned, and sequenced. Exon sequences proved highly conservative, while intron sequences yielded large differences. Intron analyses grouped species in a phylogenetic context according to the presence of two genome types: A and B. These groups are consistent with results of previous analyses, save for the novel placement of I. tiliacea, among the A-genome species. Sequences specific to both A and B genome species have been identified. Exon sequences indicate that I. ramosissima and I. umbraticola are quite different from other A-genome species. Placement of I. littoralis is questionable; its intron is similar to other B-genome species, but its exons are quite different. Exon evolution indicates that the B-genome has evolved faster than the A-genome. Interspecific intron and exon variation indicates I. trifida, I. tabascana, and I. batatas form a monophyletic group.

Volume

30

Issue

3

First Page

623

Last Page

632

ISSN

1055-7903

Disciplines

Medical Education | Medicine and Health Sciences

PubMedID

15012943

Department(s)

USF-LVHN SELECT Program

Document Type

Article

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