Characteristics and Comparative Analysis of Seven Complete Plastomes of <i>Trichoglottis</i> s.l. (Aeridinae, Orchidaceae)
<i>Trichoglottis</i> exhibits a range of rich variations in colors and shapes of flower and is a valuable ornamental orchid genus. The genus <i>Trichoglottis</i> has been expanded by the inclusion of <i>Staurochilus</i>, but this <i>Trichoglottis sensu lato&...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-09-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/24/19/14544 |
| Summary: | <i>Trichoglottis</i> exhibits a range of rich variations in colors and shapes of flower and is a valuable ornamental orchid genus. The genus <i>Trichoglottis</i> has been expanded by the inclusion of <i>Staurochilus</i>, but this <i>Trichoglottis sensu lato</i> (s.l.) was recovered as a non-monophyletic genus based on molecular sequences from one or a few DNA regions. Here, we present phylogenomic data sets, incorporating complete plastome sequences from seven species (including five species sequenced in this study) of <i>Trichoglottis</i> s.l. (including two species formerly treated as <i>Staurochilus</i>), to compare plastome structure and to reconstruct the phylogenetic relationships of this genus. The seven plastomes possessed the typical quadripartite structure of angiosperms and ranged from 149,402 bp to 149,841 bp with a GC content of 36.6–36.7%. These plastomes contain 120 genes, which comprise 74 protein-coding genes, 38 tRNA genes, and 8 rRNA genes, all <i>ndh</i> genes were pseudogenized or lost. A total of 98 (<i>T</i>. <i>philippinensis</i>) to 134 (<i>T</i>. <i>ionosma</i>) SSRs and 33 (<i>T</i>. <i>subviolacea</i>) to 46 (<i>T</i>. <i>ionosma</i>) long repeats were detected. The consistent and robust phylogenetic relationships of <i>Trichoglottis</i> were established using a total of 25 plastid genomes from the Aeridinae subtribe. The genus <i>Trichoglottis</i> s.l. was strongly supported as a monophyletic group, and two species formerly treated as <i>Staurochilus</i> were revealed as successively basal lineages. In addition, five mutational hotspots (<i>trnN<sup>GUU</sup></i>-<i>rpl32</i>, <i>trnL<sup>UAA</sup></i>, <i>trnS<sup>GCU</sup></i>-<i>trnG<sup>UCC</sup></i>, <i>rbcL</i>-<i>accD</i>, and <i>trnT<sup>GGU</sup></i>-<i>psbD</i>) were identified based on the ranking of PI values. Our research indicates that plastome data is a valuable source for molecular identification and evolutionary studies of <i>Trichoglottis</i> and its related genera. |
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| ISSN: | 1661-6596 1422-0067 |