, a new species of diploid, sexually reproductive ferns of Dryopteridaceae from Yunnan, southwestern China, is described and illustrated. Morphologically, is similar to but unique in elongated lanceolate laminae, sessile or subsessile pinna stalks, and overlapping membranous scales adnate to stipe base. Phylogenetic analyses based on both plastome and the nuclear gene sequences showed that is sister to .
View Article and Find Full Text PDFBackground: Polypodiales suborder Dennstaedtiineae contain a single family Dennstaedtiaceae, eleven genera, and about 270 species, and include some groups that were previously placed in Dennstaedtiaceae, Hypolepidaceae, Monachosoraceae, and Pteridaceae. The classification and phylogenetic relationships among these eleven genera have been poorly understood. To explore the deep relationships within suborder Dennstaedtiineae and estimate the early diversification of this morphologically heterogeneous group, we analyzed complete plastomes of 57 samples representing all eleven genera of suborder Dennstaedtiineae using maximum likelihood and Bayesian inference.
View Article and Find Full Text PDFStructural variation of plastid genomes (plastomes), particularly large inversions and gene losses, can provide key evidence for the deep phylogeny of plants. In this study, we investigated the structural variation of fern plastomes in a phylogenetic context. A total of 127 plastomes representing all 50 recognized families and 11 orders of ferns were sampled, making it the most comprehensive plastomic analysis of fern lineages to date.
View Article and Find Full Text PDFsect. is a small section of ferns with about 12 species mainly distributed in East Asia. Here, we carried out morphological and phylogenetic analyses of this section.
View Article and Find Full Text PDFComprising about 82% of the extant fern species diversity, Polypodiales are generally believed to have diversified in the Late Cretaceous. We estimated the divergence times of Polypodiales using both penalized likelihood and Bayesian methods, based on a dataset consisting of 208 plastomes representing all 28 families and 14 fossil constraints reflecting current interpretations of fossil record. Our plastome phylogeny recovered the same six major lineages as a recent nuclear phylogeny, but the position of Dennstaedtiineae was different.
View Article and Find Full Text PDFCytidine-to-uridine (C-to-U) RNA editing is common in coding regions of organellar genomes throughout land plants. In most cases RNA editing alters translated amino acids or creates new start codons, potentially confounds phylogenetic reconstructions. In this study, we used the spike moss genus (lycophytes), which has the highest frequency of RNA editing, as a model to test the effects of extreme RNA editing on phylogenetic reconstruction.
View Article and Find Full Text PDFMitochondrial DNA B Resour
July 2019
(Baker) Christ is an endangered fern species endemic to southwest China. In this study, we sequenced the complete plastid genome of . The gene order and structure of the plastome are similar to those published plastomes in Polypodiales.
View Article and Find Full Text PDFDNA barcoding is a fast-developing technique to identify species by using short and standard DNA sequences. Universal selection of DNA barcodes in ferns remains unresolved. In this study, five plastid regions (rbcL, matK, trnH-psbA, trnL-F and rps4-trnS) and eight nuclear regions (ITS, pgiC, gapC, LEAFY, ITS2, IBR3_2, DET1, and SQD1_1) were screened and evaluated in the fern genus Adiantum from China and neighboring areas.
View Article and Find Full Text PDFPremise Of The Study: Biogeographic analyses of ferns with an eastern Asian-North American disjunction are few. The Adiantum pedatum complex has such a disjunct distribution. The monophyly of the complex needs to be tested and diversification history of the four species needs to be reconstructed.
View Article and Find Full Text PDFAdiantum consists of about 150-200 species mostly with a pantropical distribution, yet the classifications of Adiantum have been based primarily on regional studies. Confounding the clarity of reconstructing the evolutionary history of Adiantum is that previous molecular phylogenetic studies suggest that a separate and distinctive clade, the vittarioids, may be derived from within Adiantum. Five plastid markers (atpA, atpB, rbcL, trnL-F and rps4-trnS) are employed to assess the monophyly of Adiantum, and construct the molecular phylogeny of Chinese Adiantum.
View Article and Find Full Text PDFBased on field investigation and laboratory analysis, exploration was done of distribution of macro and micro elements in the soils and distribution of longevity population in Xiayi County, Henan Province, China, and relationship between the spatial variation of the distribution of soil elements and the distribution of the longevity population. It was found that longevity population was distributed in a belt running across Xiayi county from northeast to southwest. In the northeast part, the longevity rate (over 95 years old) reached 187 per million and while in the northwest part, it was only 83.
View Article and Find Full Text PDFSwertia mussotii is an important species in Tibetan folk medicine. However, it is quite expensive and frequently adulterated, so reliable methods for authentication of putative specimens and preparations of the species are needed to protect consumers and to support conservation measures. We show here that the chloroplast (cp) DNA RPL16 intron has limited utility for differentiating S.
View Article and Find Full Text PDFCyrtomium is an Asiatic genus characterized by anastomosing veins with included veinlets, and comprises about 40 species. We sequenced rbcL and trnL-F sequences of 19 species of Cyrtomium and eight species from related genera in order to elucidate a molecular phylogeny of the genus using maximum-parsimony methods. The phylogenetic trees did not agree with traditional classifications.
View Article and Find Full Text PDF