The Experts below are selected from a list of 2505 Experts worldwide ranked by ideXlab platform

Jose Mathew - One of the best experts on this subject based on the ideXlab platform.

James F Smith - One of the best experts on this subject based on the ideXlab platform.

  • familial placement and relations of rehmannia and triaenophora scrophulariaceae s l inferred from five gene regions
    American Journal of Botany, 2009
    Co-Authors: Zhi Xia, Yinzheng Wang, James F Smith
    Abstract:

    Accurate classification systems based on evolution are imperative for biological investigations. The recent explosion of molecular phylogenetics has resulted in a much improved classification of angiosperms. More than five phylogenetic lineages have been recognized from Scrophulariaceae sensu lato since the family was determined to be polyphyletic; however, questions remain about the genera that have not been assigned to one of the segregate families of Scrophulariaceae s.l. Rehmannia Liboschitz and Triaenophora Solereder are such genera with uncertain familial placement. There also is debate whether Triaenophora should be segregated from Rehmannia. To evaluate the phylogenetic relations between Rehmannia and Triaenophora, to find their closest relatives, and to verify their familial placement, we conducted phylogenetic analyses of the sequences of one nuclear DNA (ITS) region and four chloroplast DNA gene regions (trnL-F, rps16, rbcL, and rps2) individually and combined. The analyses showed that Rehmannia and Triaenophora are each strongly supported as monophyletic and together are sister to Orobanchaceae. This relation was corroborated by phytochemical and morphological data. Based on these data, we suggest that Rehmannia and Triaenophora represent the second nonparasitic branch sister to the remainder of Orobanchaceae (including Lindenbergia).

Zhi Xia - One of the best experts on this subject based on the ideXlab platform.

Sarah Mathews - One of the best experts on this subject based on the ideXlab platform.

  • Primers for Castilleja and their utility across Orobanchaceae: II. Single-copy nuclear loci.
    Applications in plant sciences, 2017
    Co-Authors: Maribeth Latvis, Sarah Mathews, Sebastian M. E. Mortimer, Sarah J. Jacobs, Melissa Richards, Paul D. Blischak, David C. Tank
    Abstract:

    Premise of the study: We developed primers targeting nuclear loci in Castilleja with the goal of reconstructing the evolutionary history of this challenging clade. These primers were tested across other major clades in Orobanchaceae to assess their broader utility. Methods and Results: We assembled low-coverage genomes for three taxa in Castilleja and developed primer combinations for the single-copy conserved ortholog set (COSII) and the pentatricopeptide repeat (PPR) gene family. These primer combinations were designed to take advantage of the Fluidigm microfluidic PCR platform and are well suited for high-throughput sequencing applications. Eighty-seven primers were designed for Castilleja, and 27 were found to have broader utility in Orobanchaceae. Conclusions: These results demonstrate the utility of these primers, not only across Castilleja, but for other lineages within Orobanchaceae as well. This expanded molecular toolkit will be an asset to future phylogenetic studies in Castilleja and throughou...

  • Primers for Castilleja and their Utility Across Orobanchaceae: I. Chloroplast Primers
    Applications in plant sciences, 2017
    Co-Authors: Maribeth Latvis, Sarah Mathews, Sebastian M. E. Mortimer, Diego F. Morales-briones, Samuel Torpey, Simon Uribe-convers, Sarah J. Jacobs, David C. Tank
    Abstract:

    Premise of the study: Chloroplast primers were developed from genomic data for the taxonomically challenging genus Castilleja. We further tested the broader utility of these primers across Orobanchaceae, identifying a core set of chloroplast primers amplifying across the clade. Methods and Results: Using a combination of three low-coverage Castilleja genomes and sequence data from 12 Castilleja plastomes, 76 primer combinations were specifically designed and tested for Castilleja. The primers targeted the most variable portions of the plastome and were validated for their applicability across the clade. Of these, 38 primer combinations were subsequently evaluated in silico and then validated across other major clades in Orobanchaceae. Conclusions: These results demonstrate the utility of these primers, not only across Castilleja, but for other clades in Orobanchaceae— particularly hemiparasitic lineages—and will contribute to future phylogenetic studies of this important clade of parasitic plants.

  • phylogeny of the parasitic plant family Orobanchaceae inferred from phytochrome a
    American Journal of Botany, 2006
    Co-Authors: Jonathan R Bennett, Sarah Mathews
    Abstract:

    Partial sequences of the nuclear gene encoding the photoreceptor phytochrome A (PHYA) are used to reconstruct relationships within Orobanchaceae, the largest of the parasitic angiosperm families. The monophyly of Orobanchaceae, including nonphotosynthetic holoparasites, hemiparasites, and nonparasitic Lindenbergia is strongly supported. Phytochrome A data resolve six well-supported lineages that contain all of the sampled genera except Brandisia, which is sister to the major radiation of hemiparasites. In contrast to previous plastid and ITS trees, relationships among these major clades also are generally well supported. Thus, the robust phylogenetic hypothesis inferred from the PHYA data provides a much better context in which to evaluate the evolution of parasitism within the group. Ninety-eight species of Orobanchaceae, representing 43 genera, are included and Brandisia, Bungea, Cymbaria, Esterhazya, Nesogenes, Phtheirospermum, Radamaea, Siphonostegia, and Xylocalyx are confirmed as members of Orobanchaceae. The earliest diverging lineage of hemiparasites is identified for the first time; it contains Bungea, Cymbaria, Monochasma, Siphonostegia, and the monotypic Schwalbea, which is federally endangered. This basal clade is marked by the presence of two novel introns. A second, apparently independent gain of one of these introns marks a clade of largely European taxa. There is significant rate heterogeneity among PHYA sequences, and the presence of multiple PHYA in some taxa is consistent with observed ploidy levels.

Antonio Jose Pujadas Salva - One of the best experts on this subject based on the ideXlab platform.