rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    non sort: A
    title: biosystematic study of Panicum section Diffusa (Poaceae) in North America
  name:
    name part: Waller, Floyd Robert.
    role:
      role term: creator
  name:
    name part: Fryxell, Paul A.
    role:
      role term: degree committee member.
  name:
    name part: Gould, Frank W.
    role:
      role term: degree supervisor.
  name:
    name part: Hart, Gary E.
    role:
      role term: degree committee member.
  name:
    name part: Sperry, John J.
    role:
      role term: degree supervisor.
  name:
    name part: Texas A & M University
    role:
      role term: degree granting institution.
  type of resource: text
  genre: bibliography
  genre: Academic theses
  origin info:
    place:
      place term: txu
    date issued: 1976
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: print
    extent: ix, 123 leaves : illustrations ; 28 cm
  abstract: A taxonomic study was made of Panicum section Diffusa in North America. The following taxa were included: P. diffusum, P. bergii, P. capillarioides, P. filipes, P. furvum, P. ghiesbreghtii, P. hallii, P. hirsutum, P. lepidulum, P. pilcomayense, and P. tamaulipense. Panicum tamaulipense was described as a new species, and a new combination, P. hallii var. filipes, was made. The description of P. furvum was emended. Distributional range of P. diffusum was extended, and its confusion with P. hallii, P. filipes, and P. pilcomayense was clarified. Anatomical studies did not provide any new characters to delimit taxa. Culms had hollow internodes with three peripheral rings of vascular bundles. Transverse sections of the leaf were typically panicoid with radiating chlorenchyma, usually two bundle sheaths per vascular bundle, and bulliform cells in groups of 3-7. The epidermis was panicoid, with macro- and microhairs, stomata usually in two rows between the veins, and with low dome-shaped subsidiary cells, the short cells dumbbell or cross shaped, or occasionally nodular, and short cells in rows of 2 - many. Previous chromosome counts of 2n=18 for P. hallii var. hallii and P. hallii var. filipes, and 2n=36 for P. pilcomayense were confirmed. New chromosome counts reported: 2n=36 for P. diffusum and P. hirsutum. All meiotic divisions observed were regular and studies of megasporogenesis indicated the taxa to be sexual. Embryo sac development of the Adoxa type was recorded as the second record of this type for grasses. Measurements of stomatal size indicated a possible correlation with ploidy level..
  note: by Floyd Robert Waller, Jr.
  note: "Major Subject: Botany (Plant Taxonomy)."
  note: Vita.
  note: Texas A & M University
  note: Includes bibliographical references (leaves 120-122).
  subject:
    topic: Panicum
  subject:
    topic: Botany (Plant Taxonomy)
  subject:
    topic: Panicum
  identifier: http://proxy.library.tamu.edu/login
  identifier: https://hdl.handle.net/1969.1/DISSERTATIONS-508793
  related item:
    location:
      url: http://proxy.library.tamu.edu/login
  related item:
    location:
      url: https://hdl.handle.net/1969.1/DISSERTATIONS-508793
  record info:
    record content source: TXA
    record creation date: 761008
    record change date: 20220103135047.0
    record identifier: in00000509324
    language of cataloging:
      language term: eng