Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Apr 30:10:528.
doi: 10.3389/fpls.2019.00528. eCollection 2019.

Does the Enigmatic Wightia Belong to Paulowniaceae (Lamiales)?

Zhi Xia  1 , Jun Wen  2 , Zhiming Gao  1
Affiliations

Does the Enigmatic Wightia Belong to Paulowniaceae (Lamiales)?

Zhi Xia et al. Front Plant Sci. .

Abstract

The familial placement of Wightia has been controversial in the Lamiales, and the genus is currently placed in Paulowniaceae in APG IV. Phylogenetic analyses of Wightia and its close relatives in Lamiales are conducted using sequences of the complete chloroplast genomes as well as sequence data from nine chloroplast DNA regions (atpB, matK, ndhF, psbBTNH, rbcL, rps4, rps16 intron, trnL-F, and trnV-atpE) and one mitochondrial gene rps3. The maximum likelihood and Bayesian analyses do not support a close relationship between Wightia and Paulownia of Paulowniaceae; instead the enigmatic Wightia is sister to Phrymaceae with strong support in all analyses. Hence Wightia should not be placed in Paulowniaceae. Because morphological data show Wightia's affinity to both Phrymaceae and Paulowniaceae and prior nrITS data suggest its sister relationship to Paulownia of Paulowniaceae, it is likely that Wightia may have had a hybrid origin between early lineages of Phrymaceae and Paulowniaceae. It is therefore the best to exclude Wightia from Paulowniaceae and place the genus as unassigned until further nuclear data to test the hybrid hypothesis. The seven species of Paulownia constitute a monophyletic group, and Paulowniaceae is supported to be a monogeneric family, consistent with a series of morphological and floral development characters. The genus Brandisia, which was sometimes regarded as a close relative of Wightia, is supported to be nested within Orobanchaceae, as sister to Pterygiella. This sister relationship can be corroborated by fruit, seed and pollen morphological characters.

Keywords: Brandisia; Paulownia; Scrophulariaceae; Wightia; familial placement; phylogenetic relationship.

PubMed Disclaimer

Figures

FIGURE 1
FIGURE 1
Gene map of the chloroplast genome of Wightia speciosissima.
FIGURE 2
FIGURE 2
Bayesian tree based on the combined nine plastid markers (atpB, matK, ndhF, psbBTNH, rbcL, rps4, rps16 intron, trnL-F, and trnV-atpE). Number above branches are ML bootstrap values/Bayesian posterior. An asterisk indicates bootstrap value of 100 or posterior probability of 1.00; a hyphen (-) indicates the branch was not obtained in the ML bootstrap consensus.
FIGURE 3
FIGURE 3
Bayesian tree inferred from the sequence of the protein coding genes (PCGs) of the chloroplast genome data. Numbers above branches are ML bootstrap values/Bayesian posterior probabilities. An asterisk indicates bootstrap value of 100 or posterior probability of 1.00.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Apg I. V. (2016). An update of the angiosperm phylogeny group classification for the orders and families of flowering plants: APG IV. Bot. J. Linn. Soc. 181 1–20.
    1. Argue C. L. (1980). Pollen morphology in the genus Mimulus (Scrophulariaceae) and its taxonomic significance. Am. J. Bot. 67 68–87.
    1. Armstrong J. E. (1985). The delimitation of Bignoniaceae and Scrophulariaceae based on floral anatomy and the placement of problem genera. Am. J. Bot. 72 755–766.
    1. Bankevich A., Nurk S., Antipov D., Gurevich A. A., Dvorkin M., Kulikov A. S., et al. (2012). SPAdes: a new genome assembly algorithm and its applications to single-cell sequencing. J. Comput. Biol. 19 455–477. 10.1089/cmb.2012.0021 - DOI - PMC - PubMed
    1. Beardsley P. M., Olmstead R. G. (2002). Redefining Phrymaceae: the placement of Mimulus, tribe Mimuleae, and Phryma. Am. J. Bot. 89 1093–1102. 10.3732/ajb.89.7.1093 - DOI - PubMed