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Filtering by: Creator Davis, Curtiss O. Remove constraint Creator: Davis, Curtiss O. Academic Affiliation Botany and Plant Pathology Remove constraint Academic Affiliation: Botany and Plant Pathology Advisor Chambers, Kenton L. Remove constraint Advisor: Chambers, Kenton L.

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  • The ecology and reproduction of Sophora leachiana Peck (Fabaceae)

    Creator:
    Crowder, Cheryl Alison
    Abstract:
    The goal of the study was to collect data on the ecology and reproduction of Sophora leachiana in order to help explain the rarity and restricted range of this species. There are 13 known populations of S. leachiana, occurring in a 29 by 6.4 km area in the Siskiyou Mountains...
    Resource Type:
    Masters Thesis
    Full Text:
    o Graduate School Date thesis is presented IncplcAn Vli 1 Cir)5< Typed by CAMPUS PRINTING & COPY

  • Cytotaxonomic studies in the Artemisia ludoviciana polyploid complex of the Pacific Northwest

    Creator:
    Estes, James R.
    Abstract:
    The Artemisia ludoviciana polyploid complex is a highly polymorphic assembledge of eight taxa in the Pacific Northwest, with a chromosome base number of x=9. A cytogenetic analysis of this complex was carried out to determine the sources of its variation, the types of polyploidy present, and the genetic processes active...
    Resource Type:
    Dissertation
    Full Text:
    (Stebbins, 1950, p. 308- 335; Jones, 1961; Davis and Heywood, 1963, p. 215-225) must be reevaluated. As

  • Origin and distribution of polyploid Achillea (Compositae) in western North America

    Creator:
    Tyrl, Ronald J.
    Abstract:
    A cytogeographical study was made of populations of tetraploid (n=18) and hexaploid (n=27) Achillea millefolium (Compositae- Anthemideae) from the Pacific Coast states. There is a complex distributional pattern, involving overlapping ranges, mixed populations, migration of one form into areas occuplied by the other, pentaploid hybrids, and septaploid and octoploid plants....
    Resource Type:
    Dissertation
    Full Text:
    chromosome number (Stebbins, 1950; Davis & Heywood, 1963). This complete morphological and ecological

  • A biosystematic study in the genus Aster, section Aster, in western North America

    Creator:
    Dean, Milton Lee
    Abstract:
    A biosystematic investigation was undertaken in 15 species and three subspecies of the genus Aster, in western North America. Previous studies had been based entirely on external morphological features, and it was believed that much could be learned about the natural affinities of the taxa by exploring their cytological and...
    Resource Type:
    Dissertation
    Full Text:
    . Pollen stainability of plants used in hybridizations . . . o . o 46 III. Comparative pollen grain size

  • A revision of Juncus subgenus genuini (Juncaceae) in the Pacific states

    Creator:
    Lint, Harold LeRoy
    Abstract:
    A study was made of the subgenus Genuini of the genus Juncus in the Pacific States, California, Oregon and Washington. Extensive morphological comparisons, geographical distributions, habitat differences and observations of apparent presence or absence of natural hybrids provided the major data sources. Cytological studies were made, but were inconclusive. Eleven...
    Resource Type:
    Dissertation
    Full Text:
    (Benson 1962, Davis and Haywood 1963) 17 regarding the respective merits of using "subspecies" or

  • Phenotypic variation in diploid and tetraploid populations of Claytonia perfoliata (s.l.) (Portulacaceae)

    Creator:
    Miller, John M.
    Abstract:
    Meiotic chromosome counts from 200 populations of Claytonia (Montia) perfoliata (sensu lato) reveal a polyploid pillar complex based on three morphologically different, chemically distinct, and geographically defined diploids. The basic chromosome number is x=6. Diploid C. perfoliata Willdenow with linear juvenile leaves and deltoid mature basal leaves ranges southeastward from...
    Resource Type:
    Dissertation
    Full Text:
    University), Dr. Henrietta Chambers, Dr. Leslie D. Gottleib (University of California, Davis), Dr. G

  • Taxonomy of Phacelia section Miltitzia (hydrophyllaceae)

    Creator:
    Halse, Richard R.
    Abstract:
    A systematic study was made of the species comprising Phacelia section Miltitzia. These species, which are commonly found in the Great Basin physiographic province of western North America, are distinguished from other members of Phacelia by their yellow, marcescent corollas and their transversely corrugated seeds. This project utilized morphological, cytological,...
    Resource Type:
    Dissertation
    Full Text:
    monoensis seed (87X) 24 fr *0 ; '" si sa i/P or e7 -J .,N o. "1 - a P Le w ii, te r A . c

  • Reevaluation of systematic relationships in Triticum L. and Aegilops L. based on comparative morphological and anatomical investigations of dispersal mechanisms

    Creator:
    Morrison, Laura A.
    Abstract:
    Comparative morphological and anatomical studies of the dispersal mechanisms characterizing the wheat complex (Triticum L. and Aegilops L.) have documented patterns of adaptive radiation which may have significance for evolutionary relationships. These patterns, which form an array of diverse types of diaspores among the diploid taxa, appear conceptually to have...
    Resource Type:
    Dissertation
    Full Text:
    LIVHead of Department of Botany & P1 t o ogy Dean of Graduate Sc I understand that my thesis will

  • Biosystematics of a Western North American polyploid complex in the genus aster

    Creator:
    Guppy, Geraldine Anne Allen
    Abstract:
    Species relationships were investigated in a western North American polyploid complex in the genus Aster (Asteraceae). A combination of cytological, genetical, chemical, morphological and numerical approaches was employed. Fifteen presently recognized species were included in the study, and populations were sampled throughout most of the range of the group. Living...
    Resource Type:
    Dissertation

  • A systematic study of Lathyrus vestitus Nutt. ex T. & G. (Fabaceae) and allied species of the Pacific Coast

    Creator:
    Broich, Steven L.
    Abstract:
    Eight species of Lathvrus (Fabaceae, Faboideae) endemic to the Pacific Coast of North America were the subject of a systematic investigation. Taxa studied included Lathvrus vestitus, Nutt. ex T. & G., L. laetif lorus Greene, L.. iepsonii Greene, £,. splendens Kellogg, L. polvphvllus, Nutt. ex T. & G., L. holochlorus...
    Resource Type:
    Dissertation
    Full Text:
    (Fedchenko 1948; Davis 1970; Czfranova 1971). None of these schemes take into account North and South