DOCSLIB.ORG

Variation in Structural Gender in the Hermaphrodite Helleborus Foetidus (Ranunculaceae): Within- and Among-Population Patterns

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Variation in Structural Gender in the Hermaphrodite Helleborus Foetidus (Ranunculaceae): Within- and Among-Population Patterns Plant Syst. Evol. 241: 139–151 (2003) DOI 10.1007/s00606-003-0046-6 Variation in structural gender in the hermaphrodite Helleborus foetidus (Ranunculaceae): within- and among-population patterns J. Guitia´n1, M. Medrano1,2, C. M. Herrera2, and A. M. Sa´nchez-Lafuente2 1Departamento de Biologı´a Vegetal, Universidad de Santiago de Compostela, Santiago de Compostela, Spain 2Estacio´n Biolo´gica de Don˜ ana, Sevilla, Spain Received May 22, 2002; accepted February 19, 2003 Published online: November 4, 2003 Ó Springer-Verlag 2003 Abstract. In hermaphrodite plants, variations in Key words: Helleborus foetidus, structural gender, structural gender (defined as the ratio between male sex allocation, trade-offs, pollen:ovule ratio. and female gametes) may occur at different levels (among flowers, plants, and populations). In this study, we investigated variation in four traits Introduction influencing structural gender (number of carpels, Since Darwin’s publication of The Different ovules per carpel, stamens, and pollen grains per Forms of Flowers on Plants of the Same Species stamen) within and among six distant populations (1877), there has been a continuing effort to of the hermaphrodite perennial herb Helleborus foetidus (Ranunculaceae) in the Iberian Peninsula. understand the process of plant sexual repro- Our results show that the four traits investigated duction and, more specifically, gender special- varied significantly at all levels considered. Traits ization. A critical step in the understanding of influencing the female sexual component (number gender specialization was the recognition that of carpels and ovules per carpel) showed greater in flowering plants, hermaphroditism does not variation at the lowermost levels (within flower and necessarily mean equi-sexuality, i.e. a balanced plant) than traits influencing the male component, gender with roughly similar contributions by which in turn varied more markedly among pop- male and female functions to reproduction ulations. Number of carpels per flower and number (Horovitz 1978). Following Horovitz’s (1978) of pollen grains per anther were the most important and Lloyd’s (1980a, b; 1984) initial insight, traits affecting between-plant variation in structural numerous studies have subsequently examined gender. There was no evidence of significant plant- patterns of variation in gender and sex expres- level trade-offs or correlations between the various male and female traits, which covaried differently sion in plants with hermaphroditic flowers, across populations. The observed between-popula- both from empirical and theoretical viewpoints tion variation in structural gender of Helleborus (e. g. Charlesworth and Charlesworth 1981; foetidus can be explained as a consequence of Charnov 1982; Queller 1983; Lloyd and Bawa differences in self-pollination levels related to a 1984; Broyles and Wyatt 1990, 1995; Mazer flower’s ‘‘mating environment’’. and Delesalle 1998). 140 J. Guitia´n et al.: Gender variation in Helleborus foetidus Although most investigations have recog- 1977, Mazer and Hultga˚ rd 1993, Mazer and nized two different quantitative measures Delesalle 1998, Cruden 2000, Wyatt et al. of plant gender, namely structural 2000, Ju¨ rgens et al. 2002). ( ¼ phenotypic) and functional gender (Lloyd Patterns of intraspecific variation in struc- 1980a, Lloyd and Bawa 1984), the most tural gender are interesting in their own right frequently emphasized measure has tended to for at least three reasons. First, structural be functional gender, i.e., the relationship gender is a critical factor in determining between the proportion of seeds produced functional gender. All else being equal, indi- and the proportion of seeds sired by a given vidual variation in structural gender will be individual. Reliable assessment of the func- mirrored by differences in functional gender. tional gender of a given individual requires Second, intraspecific patterns of variation in knowledge not only of the number of pollen the number of male and female gametes at the grains and seeds produced by that individual, individual flower level may provide insight into but also of sex ratio, selfing levels and levels of the relative importance of male and female inbreeding depression in the population (Lloyd functions as evolutionary driving forces for 1980a, b). Functional gender is effectively an floral phenotypes. For example, the compara- estimate of the relative proportions of an tive extent of individual variability in male- individual’s fitness that are realized via male and female-related traits may inform us about and female functions, a question that would which of the two sexual functions has played a appear to be critical for the evolution of many greater selective role in shaping floral struc- reproductive features, such as floral display tural traits (Stanton et al. 1986). Third, a and inflorescence design (Cruzan et al. 1988, conspicuous trend exists in angiosperm evolu- Fishbein and Venable 1996, Fritz and Nilsson tion, from basal primitive lineages with an 1996). Relatively few studies, however, have indeterminate number of male and female attempted a detailed examination of patterns gamete-bearing structures, towards more ad- of variation in structural gender in hermaph- vanced lineages with extraordinarily reduced roditic species. By structural gender we mean variability in the number of such structures per the relative number of male and female flower (Stebbins 1974). The study of patterns gametes produced by an individual plant. of intraspecific variation in structural gender in Clearly, measuring structural gender in natural some of these primitive lineages may provide populations, and assessing its patterns of insight into some of the factors potentially variation, are considerably easier than involved in these macroevolutionary patterns measuring functional gender. Why, then, the characterizing angiosperm floral evolution. relative neglect of structural gender as an This paper presents a descriptive analysis objective of plant reproduction studies? One of patterns of variation in structural gender possible reason is that number of stamens, within and among six distant populations of carpels and ovules generally exhibit little or no the hermaphroditic perennial herb Helleborus intraspecific variability, and these floral traits foetidus (Ranunculaceae) in the Iberian Penin- are commonly used to separate families and sula. This species is particularly well suited to genera (Cronquist 1981), so little opportunities this type of inquiry, as it exhibits broad seems to be left for variability to occur in intraspecific variation in all the four floral structural gender in most plants. Perhaps for traits that may contribute to variation in this reason, most studies that have examined structural gender, namely number of carpels the relationship between the number of pollen per flower, number of ovules per carpel, grains and the number of ovules (pollen:ovule number of stamens per flower, and number ratio) have focused on interspecific variation, of pollen grains per anther. Our objectives are and have largely ignored the possibility of (1) to document patterns of within and significant intraspecific variation (Cruden between population variation in structural J. Guitia´n et al.: Gender variation in Helleborus foetidus 141 gender of individual plants; (2) to assess the study these plants were pooled into a single data relative magnitudes of individual variability in set, because preliminary analyses showed almost no the male- and female-related components of variation between populations in a given region in structural gender, and determine the relative any of the four traits analyzed. Five flowers were importance of variation in each of these four collected from 26–67 plants in each population, and components as determinants of individual var- preserved in 2.5–2.5–95% formaldehyde-acetic acid-ethyl alcohol (FAA). The number of stamens iation in structural gender; and (3) to identify and carpels, and the number of ovules per possible trade-offs between same-sex compo- carpel, were determined for all collected flowers. nents (e.g. number of stamens vs. number of To account for possible differences in the number pollen grains per anther, number of carpels vs. of carpels and stamens between early- and late- number of ovules per carpel) and between opening flowers, we attempted to sample flowers in different-sex components (total number of each locality as closely as possible to the local ovules vs. total number of pollen grains). flowering peak. A subset of the flowers collected in 1999 (from CAU, MAG, MON, GRA and PIR; Fig. 1) was Material and methods used for pollen counting. Pollen was counted using a particle counter (Coulter CounterÒ Z2, Beckman Study system. Helleborus foetidus L. is a self- Coulter Inc.) equipped with a 100 lm aperture tube compatible, perennial herb distributed over much and a particle-size channelizer accessory. From of western, central and southwestern Europe (Wer- each flower we removed a subsample of completely ner and Ebel 1994). In the Iberian Peninsula, it closed anthers and separately counted the number typically occurs in clearings, forest edges, and the of pollen grains in each (N ¼ 1380 anthers, 1–5 understory of deciduous and mixed forests. Flow- anthers per flower; N ¼ 314 flowers, 1–5 flowers per ering mainly takes place from January to March. plant; N ¼ 76 plants, 10–25 plants per population). Plants consist of one to several ramets that develop Each anther was placed in a clean 1.5 ml polypro- a terminal inflorescence
Load more

Recommended publications
  • “Don't Plant a Pest: Central Coast” Brochure
    G roundcovers & Perennials G roundcove rs & Perennials G roundcove rs & Perennials G a rdening green Many of the characteristics that make a G roundcove rs plant a good choice for the garden may Instead of periwinkle, wild ginger also make it a successful invader: & Perennials DON’T PLAN T: English ivy or Algerian ivy, (Asarum caudatum) Don’t California is a gardener’s dream. Our mild climate allows A California native, this Garden Plants Invasive Plants us to have fantastic gardens, showcasing a wide variety periwinkle evergreen groundcover has Easy to propagate Broad germination T RY THESE VARIETIES: of ornamental plants from DON’T PLAN T: (Vinca major) heart-shaped leaves and unusual Establish rapidly Colonizer all around the world. This aggressive grower pachysandra maroon flowers. Mature early Mature early iceplant or Hottentot fig Howitt, © 1999 Beatrice F. Calif. Academy of Sciences has trailing stems that Plant a But sometimes, our Abundant flowers Prolific seeds (Carpobrotus edulis) (Pachysandra terminalis) root wherever they touch bear’s foot hellebore garden plants “jump the Pest / disease tolerant Few natural predators Small mammals can carry seeds of Grows more slowly than Vinca the soil. This ability to and Hedera, but has a crisp, (Helleborus foetidus) fence” and invade natural iceplant from landscape settings to resprout from stem areas. These invasive nearby coastal dunes and other neat growth form. New foliage Unusual foliage and delicate, Invasive plants are by nature a regional problem. A plant fragments enables is bright green, changing to complex flowers. The intriguing plants can become serious sensitive areas. The vigorous Alfred Brousseau, © 1995 Br.
    [Show full text]
  • Perennials for Winter Gardens Perennials for Winter Gardens
    TheThe AmericanAmerican GARDENERGARDENER® TheThe MagazineMagazine ofof thethe AAmericanmerican HorticulturalHorticultural SocietySociety November / December 2010 Perennials for Winter Gardens Edible Landscaping for Small Spaces A New Perspective on Garden Cleanup Outstanding Conifers contents Volume 89, Number 6 . November / December 2010 FEATURES DEPARTMENTS 5 NOTES FROM RIVER FARM 6 MEMBERS’ FORUM 8 NEWS FROM THE AHS Boston’s garden contest grows to record size, 2011 AHS President’s Council trip planned for Houston, Gala highlights, rave reviews for Armitage webinar in October, author of article for The American Gardener receives garden-writing award, new butterfly-themed children’s garden installed at River Farm. 12 2010 AMERICA IN BLOOM AWARD WINNERS Twelve cities are recognized for their community beautification efforts. 42 ONE ON ONE WITH… David Karp: Fruit detective. page 26 44 HOMEGROWN HARVEST The pleasures of popcorn. EDIBLE LANDSCAPING FOR SMALL SPACES 46 GARDENER’S NOTEBOOK 14 Replacing pavement with plants in San BY ROSALIND CREASY Francisco, soil bacterium may boost cognitive With some know-how, you can grow all sorts of vegetables, fruits, function, study finds fewer plant species on and herbs in small spaces. earth now than before, a fungus-and-virus combination may cause honeybee colony collapse disorder, USDA funds school garden CAREFREE MOSS BY CAROLE OTTESEN 20 program, Park Seed sold, Rudbeckia Denver Looking for an attractive substitute for grass in a shady spot? Try Daisy™ wins grand prize in American moss; it’ll grow on you. Garden Award Contest. 50 GREEN GARAGE® OUTSTANDING CONIFERS BY RITA PELCZAR 26 A miscellany of useful garden helpers. This group of trees and shrubs is beautiful year round, but shines brightest in winter.
    [Show full text]
  • Don't Plant a Pest!
    Many of the characteristics that make a plant Gardening green an attractive choice for the garden may also make it a successful invader: California is a gardener’s dream. Our mild climate Don’t allows us to have fantastic gardens, showcasing a wide Garden Plants: Invasive Plants: variety of ornamental Easy to propagate Broad germination plants from all around Establish rapidly Colonizer the world. Mature early Mature early Abundant flowers Prolific seeds plant a But sometimes, our Pest/disease tolerant Few natural predators garden plants “jump the fence” and invade Invasive plants are by nature a regional problem. A natural areas. These plant that jumps out of the garden in one climate and invasive plants can habitat type may behave perfectly in another. The become serious wildland twelve problem plants listed here have escaped from pest! weeds that threaten gardens throughout the greater Bay Area. California’s biodiversity and economy. How to use this brochure: This brochure suggests safe alternatives for these More than half of the plants. When you are buying new plants, consider these Give them an inch and plants currently Conservancy Nature The Rice, Barry alternatives, or ask your local nursery for other damaging California’s French broom invades Bay Area hillsides non-invasive plants. If one of the invasive plants is wildlands were originally introduced for landscaping already in your yard, especially if you live near they’ll take an acre... purposes. Garden escapes like pampasgrass and Scotch wildlands, you may want to remove it and replace it broom may have desirable characteristics in a garden with a recommended alternative.
    [Show full text]
  • Wood and Bark Anatomy of Ranunculaceae (Including Hydrastis) and Glaucidiaceae Sherwin Carlquist Santa Barbara Botanic Garden
    Aliso: A Journal of Systematic and Evolutionary Botany Volume 14 | Issue 2 Article 2 1995 Wood and Bark Anatomy of Ranunculaceae (Including Hydrastis) and Glaucidiaceae Sherwin Carlquist Santa Barbara Botanic Garden Follow this and additional works at: http://scholarship.claremont.edu/aliso Part of the Botany Commons Recommended Citation Carlquist, Sherwin (1995) "Wood and Bark Anatomy of Ranunculaceae (Including Hydrastis) and Glaucidiaceae," Aliso: A Journal of Systematic and Evolutionary Botany: Vol. 14: Iss. 2, Article 2. Available at: http://scholarship.claremont.edu/aliso/vol14/iss2/2 Aliso, 14(2), pp. 65-84 © 1995, by The Rancho Santa Ana Botanic Garden, Claremont, CA 91711-3157 WOOD AND BARK ANATOMY OF RANUNCULACEAE (INCLUDING HYDRASTIS) AND GLAUCIDIACEAE SHERWIN CARLQUIST Santa Barbara Botanic Garden 1212 Mission Canyon Road Santa Barbara, California 931051 ABSTRACT Wood anatomy of 14 species of Clematis and one species each of Delphinium, Helleborus, Thal­ ictrum, and Xanthorhiza (Ranunculaceae) is compared to that of Glaucidium palma tum (Glaucidiaceae) and Hydrastis canadensis (Ranunculaceae, or Hydrastidaceae of some authors). Clematis wood has features typical of wood of vines and lianas: wide (earlywood) vessels, abundant axial parenchyma (earlywood, some species), high vessel density, low proportion of fibrous tissue in wood, wide rays composed of thin-walled cells, and abrupt origin of multiseriate rays. Superimposed on these features are expressions indicative of xeromorphy in the species of cold or dry areas: numerous narrow late­ wood vessels, presence of vasicentric tracheids, shorter vessel elements, and strongly marked growth rings. Wood of Xanthorhiza is like that of a (small) shrub. Wood of Delphinium, Helleborus, and Thalictrum is characteristic of herbs that become woodier: limited amounts of secondary xylem, par­ enchymatization of wood, partial conversion of ray areas to libriform fibers (partial raylessness).
    [Show full text]
  • The Plant List
    the list A Companion to the Choosing the Right Plants Natural Lawn & Garden Guide a better way to beautiful www.savingwater.org Waterwise garden by Stacie Crooks Discover a better way to beautiful! his plant list is a new companion to Choosing the The list on the following pages contains just some of the Right Plants, one of the Natural Lawn & Garden many plants that can be happy here in the temperate Pacific T Guides produced by the Saving Water Partnership Northwest, organized by several key themes. A number of (see the back panel to request your free copy). These guides these plants are Great Plant Picks ( ) selections, chosen will help you garden in balance with nature, so you can enjoy because they are vigorous and easy to grow in Northwest a beautiful yard that’s healthy, easy to maintain and good for gardens, while offering reasonable resistance to pests and the environment. diseases, as well as other attributes. (For details about the GPP program and to find additional reference materials, When choosing plants, we often think about factors refer to Resources & Credits on page 12.) like size, shape, foliage and flower color. But the most important consideration should be whether a site provides Remember, this plant list is just a starting point. The more the conditions a specific plant needs to thrive. Soil type, information you have about your garden’s conditions and drainage, sun and shade—all affect a plant’s health and, as a particular plant’s needs before you purchase a plant, the a result, its appearance and maintenance needs.
    [Show full text]
  • An Encyclopedia of Shade Perennials This Page Intentionally Left Blank an Encyclopedia of Shade Perennials
    An Encyclopedia of Shade Perennials This page intentionally left blank An Encyclopedia of Shade Perennials W. George Schmid Timber Press Portland • Cambridge All photographs are by the author unless otherwise noted. Copyright © 2002 by W. George Schmid. All rights reserved. Published in 2002 by Timber Press, Inc. Timber Press The Haseltine Building 2 Station Road 133 S.W. Second Avenue, Suite 450 Swavesey Portland, Oregon 97204, U.S.A. Cambridge CB4 5QJ, U.K. ISBN 0-88192-549-7 Printed in Hong Kong Library of Congress Cataloging-in-Publication Data Schmid, Wolfram George. An encyclopedia of shade perennials / W. George Schmid. p. cm. ISBN 0-88192-549-7 1. Perennials—Encyclopedias. 2. Shade-tolerant plants—Encyclopedias. I. Title. SB434 .S297 2002 635.9′32′03—dc21 2002020456 I dedicate this book to the greatest treasure in my life, my family: Hildegarde, my wife, friend, and supporter for over half a century, and my children, Michael, Henry, Hildegarde, Wilhelmina, and Siegfried, who with their mates have given us ten grandchildren whose eyes not only see but also appreciate nature’s riches. Their combined love and encouragement made this book possible. This page intentionally left blank Contents Foreword by Allan M. Armitage 9 Acknowledgments 10 Part 1. The Shady Garden 11 1. A Personal Outlook 13 2. Fated Shade 17 3. Practical Thoughts 27 4. Plants Assigned 45 Part 2. Perennials for the Shady Garden A–Z 55 Plant Sources 339 U.S. Department of Agriculture Hardiness Zone Map 342 Index of Plant Names 343 Color photographs follow page 176 7 This page intentionally left blank Foreword As I read George Schmid’s book, I am reminded that all gardeners are kindred in spirit and that— regardless of their roots or knowledge—the gardening they do and the gardens they create are always personal.
    [Show full text]
  • Southern Garden History Plant Lists
    Southern Plant Lists Southern Garden History Society A Joint Project With The Colonial Williamsburg Foundation September 2000 1 INTRODUCTION Plants are the major component of any garden, and it is paramount to understanding the history of gardens and gardening to know the history of plants. For those interested in the garden history of the American south, the provenance of plants in our gardens is a continuing challenge. A number of years ago the Southern Garden History Society set out to create a ‘southern plant list’ featuring the dates of introduction of plants into horticulture in the South. This proved to be a daunting task, as the date of introduction of a plant into gardens along the eastern seaboard of the Middle Atlantic States was different than the date of introduction along the Gulf Coast, or the Southern Highlands. To complicate maters, a plant native to the Mississippi River valley might be brought in to a New Orleans gardens many years before it found its way into a Virginia garden. A more logical project seemed to be to assemble a broad array plant lists, with lists from each geographic region and across the spectrum of time. The project’s purpose is to bring together in one place a base of information, a data base, if you will, that will allow those interested in old gardens to determine the plants available and popular in the different regions at certain times. This manual is the fruition of a joint undertaking between the Southern Garden History Society and the Colonial Williamsburg Foundation. In choosing lists to be included, I have been rather ruthless in expecting that the lists be specific to a place and a time.
    [Show full text]
  • Considérations Sur L'histoire Naturelle Des Ranunculales
    Considérations sur l’histoire naturelle des Ranunculales Laetitia Carrive To cite this version: Laetitia Carrive. Considérations sur l’histoire naturelle des Ranunculales. Botanique. Université Paris Saclay (COmUE), 2019. Français. NNT : 2019SACLS177. tel-02276988 HAL Id: tel-02276988 https://tel.archives-ouvertes.fr/tel-02276988 Submitted on 3 Sep 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Considérations sur l’histoire naturelle des Ranunculales 2019SACLS177 Thèse de doctorat de l'Université Paris-Saclay : préparée à l’Université Paris-Sud NNT École doctorale n°567 : Sciences du végétal, du gène à l'écosystème (SDV) Spécialité de doctorat : Biologie Thèse présentée et soutenue à Orsay, le 05 juillet 2019, par Laetitia Carrive Composition du Jury : Catherine Damerval Directrice de recherche, CNRS (– UMR 320 GQE) Présidente du jury Julien Bachelier Professeur, Freie Universität Berlin (– Institute of Biology) Rapporteur Thomas Haevermans Maître de conférences, MNHN (– UMR 7205 ISYEB) Rapporteur Jean-Yves Dubuisson Professeur, SU (–UMR 7205 ISYEB) Examinateur Sophie Nadot Professeure, U-PSud (– UMR 8079 ESE) Directrice de thèse « Le commencement sera d’admirer tout, même les choses les plus communes. Le milieu, d’écrire ce que l’on a bien vu et ce qui est d’utilité.
    [Show full text]
  • Extreme Intraplant Variation in Nectar Sugar Composition in an Insect-Pollinated Perennial Herb1
    American Journal of Botany 93(4): 575–581. 2006. EXTREME INTRAPLANT VARIATION IN NECTAR SUGAR COMPOSITION IN AN INSECT-POLLINATED PERENNIAL HERB1 CARLOS M. HERRERA,2,4 RICARDO PE´ REZ,3 AND CONCHITA ALONSO2 2 Estacio´n Biolo´gica de Don˜ana, Consejo Superior de Investigaciones Cientı´ficas, Avenida de Marı´a Luisa s/n, E-41013 Sevilla, Spain; and 3 Instituto de Investigaciones Quı´micas, Centro de Investigaciones Cientı´ficas Isla de La Cartuja, Consejo Superior de Investigaciones Cientı´ficas, Avenida Ame´rico Vespucio s/n, E-41092 Sevilla, Spain Variation in nectar chemistry among plants, flowers, or individual nectaries of a given species has been only rarely explored, yet it is an essential aspect to our understanding of how pollinator-mediated selection might act on nectar traits. This paper describes variation in nectar sugar composition in a population of the perennial herb Helleborus foetidus (Ranunculaceae) and dissects it into components due to variation among plants, flowers of the same plant, and nectaries of the same flower. The proportions of sucrose, glucose, and fructose in single-nectary nectar samples collected at two times in the flowering season were determined using high performance liquid chromatography (HPLC). Sugar composition varied extensively among nectaries, and nearly all combinations of individual sugars were recorded. Population-wide variance was mainly accounted for by variation among flowers of the same plant (56% of total), nectaries of the same flower (30%), and only minimally by differences among plants (14%). In absolute terms, intraplant variation was similar to or greater than that ordinarily reported in interspecific comparisons.
    [Show full text]
  • The Plant List the a Better Way to Beautiful
    The Plant List The Plant THE a better way to beautiful LIST A Companion to the Choosing the Right Plants Natural Lawn & Garden Guide Waterwise garden by Stacie Crooks Discover a better way to beautiful! his plant list is a companion to Choosing the Right The list on the following pages contains just some of the Plants, one of the Natural Lawn & Garden Guides many plants that can be happy here in the temperate Pacific T (see the back panel to request your free copy). Northwest, organized by several key themes. A number of These guides will help you garden in balance with nature, so these plants are Great Plant Picks ( ) selections, chosen you can enjoy a beautiful yard that’s healthy, easy to maintain because they are vigorous and easy to grow in Northwest and good for the environment. gardens, while offering reasonable resistance to pests and diseases, as well as other attributes. (For details about the When choosing plants, we often think about factors like size, GPP program and to find additional reference materials, shape, foliage and flower color. But the most important con- refer to Resources & Credits on page 12.) sideration should be whether a site provides the conditions a specific plant needs to thrive. Soil type, drainage, sun and Remember, this plant list is just a starting point. The more shade—all affect a plant’s health and, as a result, its appear- information you have about your garden’s conditions and ance and maintenance needs. a particular plant’s needs before you purchase a plant, the better.
    [Show full text]
  • History and Update on the World of Hellebores©
    History and Update on the World of Hellebores 585 History and Update on the World of Hellebores© John E. Elsley Song Sparrow, 5200 Bryte St., Greenwood, South Carolina 29649 Email: [email protected] HELLEBORES: SPECIES AND IMPORTANT EARLY HYBRIDIZERS A working knowledge of the available species is of major importance in breeding programs. Sowing species seed provides potential hybridizers with variable prog- eny from which can be selected potential parental individuals displaying desirable characteristics. In the case of hellebores, these characteristics include both floral and foliar features combined with overall vigor. SPECIES Helleborus argutifolius. Native southern Europe/Corsica. Handsome caules- cent specimen. A superb performer in the Pacific Northwest. Magnificent, variable foliage. The bold foliage creates an attractive contrast with the heavy effect of conifer foliage, i.e., Thuja. Cultivars: ‘Janet Starnes’, speckled cream leaves; ‘Pacific Frost’, heavy cream foli- age speckling. Helleborus foetidus. Native to central Europe. Caulescent species with handsome variable foliage and terminal clusters of pendulous bell-shaped flowers. Short lived but self-seeds freely. Often flowers in second year from seed—blooms late winter, early spring. Cultivars: ‘Sienna’, dark green foliage and chartreuse flowers. Selected by Will McLewin—noted English species authority; Wester Flisk Group, red-stemmed form from east Scotland (Seeding progeny quickly looses this desirable trait if grown with non-red-stemmed forms. Doubtful if the original form exists; most are now selections from seedling strains.); Red Silver strain, a Wester Flisk Group cross with silvered leaves and reddish stems, Northwest Garden Nursery introduction; ‘Gold Bullion’ a variable seed strain with yellow foliage. Helleborus multifidus.
    [Show full text]
  • Comparative Epigenetic and Genetic Spatial Structure of the Perennial Herb Helleborus Foetidus
    RESEARCH ARTICLE AMERICAN JOURNAL OF BOTANY Comparative epigenetic and genetic spatial structure of the perennial herb Helleborus foetidus : Isolation by environment, isolation by distance, and functional trait divergence 1 Carlos M. Herrera 2 , Mónica Medrano , and Pilar Bazaga PREMISE OF THE STUDY: Epigenetic variation can play a role in local adaptation; thus, there should be associations among epigenetic variation, environ- mental variation, and functional trait variation across populations. This study examines these relationships in the perennial herb Helleborus foetidus (Ranunculaceae). METHODS: Plants from 10 subpopulations were characterized genetically (AFLP, SSR markers), epigenetically (MSAP markers), and phenotypically (20 functional traits). Habitats were characterized using six environmental variables. Isolation-by-distance (IBD) and isolation-by-environment (IBE) patterns of genetic and epigenetic divergence were assessed, as was the comparative explanatory value of geographical and environmental distance as predictors of epigenetic, genetic, and functional diff erentiation. KEY RESULTS: Subpopulations were diff erentiated genetically, epigenetically, and phenotypically. Genetic diff erentiation was best explained by geograph- ical distance, while epigenetic diff erentiation was best explained by environmental distance. Divergence in functional traits was correlated with environ- mental and epigenetic distances, but not with geographical and genetic distances. CONCLUSIONS: Results are compatible with the hypothesis that
    [Show full text]