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Multiseriate Cortical Sclerenchyma Enhance Root Penetration in Compacted Soils
Multiseriate cortical sclerenchyma enhance root penetration in compacted soils Hannah M. Schneidera, Christopher F. Strocka, Meredith T. Hanlona, Dorien J. Vanheesb,c, Alden C. Perkinsa, Ishan B. Ajmeraa, Jagdeep Singh Sidhua, Sacha J. Mooneyb,d, Kathleen M. Browna, and Jonathan P. Lyncha,b,d,1 aDepartment of Plant Science, Pennsylvania State University, University Park, PA 16802; bDivision of Agricultural and Environment Sciences, School of Biosciences, University of Nottingham, Leicestershire LE12 5RD, United Kingdom; cThe James Hutton Institute, Invergowrie DD2 5DA, United Kingdom; and dCentre for Plant Integrative Biology, University of Nottingham, Leicestershire LE12 5RD, United Kingdom Edited by Philip N. Benfey, Duke University, Durham, NC, and approved January 3, 2021 (received for review June 11, 2020) Mechanical impedance limits soil exploration and resource capture Root anatomical phenes have a large effect on penetration by plant roots. We examine the role of root anatomy in regulating ability (11). Thicker roots are more resistant to buckling and plant adaptation to mechanical impedance and identify a root deflection when encountering hard soils (12, 13). However, in anatomical phene in maize (Zea mays) and wheat (Triticum aesti- maize, cortical cell wall thickness, cortical cell count, cortical cell vum ) associated with penetration of hard soil: Multiseriate cortical wall area, and stele diameter predict root penetration and bend sclerenchyma (MCS). We characterize this trait and evaluate the strength better than root diameter (14). Smaller cells in the outer utility of MCS for root penetration in compacted soils. Roots with cortical region in maize are associated with increased root pen- MCS had a greater cell wall-to-lumen ratio and a distinct UV emis- sion spectrum in outer cortical cells. -
YELLOW-POPLAR (LIRIODENDRON TULIPIFERA L.)' George Lowerts E. A. Wheeler Robert C. Kellison
CHARACTERISTICS OF WOUND-ASSOCIATED WOOD OF YELLOW-POPLAR (LIRIODENDRON TULIPIFERA L.)' George Lowerts Forest Geneticist Woodlands Research, Union Camp Corp. Rincon, GA 31426 E. A. Wheeler Associate F'rofessor Department of Wood and Paper Science, North Carolina State University Raleigh, NC 27695-8005 and Robert C. Kellison Professor, Department of Forestry and Director, Hardwood Research Cooperative School of Forest Resoumes Raleigh, NC 27695-8002 (Received May 1985) ABSTRACT Selectedanatomical characteristicsand specificgravity ofydlow-poplar wood formed after wounding and adjacent to the wound were compared to similar characteristics of yellow-poplar wood formed before and after wounding and away from the wound. The wood formed immediately after wounding was similar anatomically to the bamer zones described for other species. Vessel volume, vessel diameter, percentage of vessel multiples, and vessel elcment length were significantly lower in wound- associated wood, while ray volume, ray density, and specific gravity were significantly greater. Such changes in the vessel system would result in a decrease in conductivity in the wounded area, while the increase in parenchyma would increase the potential for manufacture of fungitoxic compounds. With increasing radial distance from the wound area, the anatomical features of the wound-associated wood -~radualh . a~~roached .. those of normal wood, although. by. four years after wounding, the wood still had not returned to normal. The specific gravity stayed significantly greater. Keywords: Liriodendron lulipirpra L., yellow-poplar, barrier zones, wood anatomy, wounding, dis- coloration and decay. INTRODUCTION Wounds extending into the wood of branches, stems, or roots of a tree create an opportunity for the initiation of discoloration and decay. -
Development and Cell Cycle Activity of the Root Apical Meristem in the Fern Ceratopteris Richardii
G C A T T A C G G C A T genes Article Development and Cell Cycle Activity of the Root Apical Meristem in the Fern Ceratopteris richardii Alejandro Aragón-Raygoza 1,2 , Alejandra Vasco 3, Ikram Blilou 4, Luis Herrera-Estrella 2,5 and Alfredo Cruz-Ramírez 1,* 1 Molecular and Developmental Complexity Group at Unidad de Genómica Avanzada, Laboratorio Nacional de Genómica para la Biodiversidad, Cinvestav Sede Irapuato, Km. 9.6 Libramiento Norte Carretera, Irapuato-León, Irapuato 36821, Guanajuato, Mexico; [email protected] 2 Metabolic Engineering Group, Unidad de Genómica Avanzada, Laboratorio Nacional de Genómica para la Biodiversidad, Cinvestav Sede Irapuato, Km. 9.6 Libramiento Norte Carretera, Irapuato-León, Irapuato 36821, Guanajuato, Mexico; [email protected] 3 Botanical Research Institute of Texas (BRIT), Fort Worth, TX 76107-3400, USA; [email protected] 4 Laboratory of Plant Cell and Developmental Biology, Division of Biological and Environmental Sciences and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia; [email protected] 5 Institute of Genomics for Crop Abiotic Stress Tolerance, Department of Plant and Soil Science, Texas Tech University, Lubbock, TX 79409, USA * Correspondence: [email protected] Received: 27 October 2020; Accepted: 26 November 2020; Published: 4 December 2020 Abstract: Ferns are a representative clade in plant evolution although underestimated in the genomic era. Ceratopteris richardii is an emergent model for developmental processes in ferns, yet a complete scheme of the different growth stages is necessary. Here, we present a developmental analysis, at the tissue and cellular levels, of the first shoot-borne root of Ceratopteris. -
Summary a Plant Is an Integrated System Which: 1
Summary A plant is an integrated system which: 1. Obtains water and nutrients from the soil. 2. Transports them 3. Combines the H2O with CO2 to make sugar. 4. Exports sugar to where it’s needed Today, we’ll start to go over how this occurs Transport in Plants – Outline I.I. PlantPlant waterwater needsneeds II.II. TransportTransport ofof waterwater andand mineralsminerals A.A. FromFrom SoilSoil intointo RootsRoots B.B. FromFrom RootsRoots toto leavesleaves C.C. StomataStomata andand transpirationtranspiration WhyWhy dodo plantsplants needneed soso muchmuch water?water? TheThe importanceimportance ofof waterwater potential,potential, pressure,pressure, solutessolutes andand osmosisosmosis inin movingmoving water…water… Transport in Plants 1.1. AnimalsAnimals havehave circulatorycirculatory systems.systems. 2.2. VascularVascular plantsplants havehave oneone wayway systems.systems. Transport in Plants •• OneOne wayway systems:systems: plantsplants needneed aa lotlot moremore waterwater thanthan samesame sizedsized animals.animals. •• AA sunflowersunflower plantplant “drinks”“drinks” andand “perspires”“perspires” 1717 timestimes asas muchmuch asas aa human,human, perper unitunit ofof mass.mass. Transport of water and minerals in Plants WaterWater isis goodgood forfor plants:plants: 1.1. UsedUsed withwith CO2CO2 inin photosynthesisphotosynthesis toto makemake “food”.“food”. 2.2. TheThe “blood”“blood” ofof plantsplants –– circulationcirculation (used(used toto movemove stuffstuff around).around). 3.3. EvaporativeEvaporative coolingcooling. -
How Trees Modify Wood Development to Cope with Drought
DOI: 10.1002/ppp3.29 REVIEW Wood and water: How trees modify wood development to cope with drought F. Daniela Rodriguez‐Zaccaro | Andrew Groover US Forest Service, Pacific Southwest Research Station; Department of Plant Societal Impact Statement Biology, University of California Davis, Drought plays a conspicuous role in forest mortality, and is expected to become more Davis, California, USA severe in future climate scenarios. Recent surges in drought-associated forest tree Correspondence mortality have been documented worldwide. For example, recent droughts in Andrew Groover, US Forest Service, Pacific Southwest Research Station; Department of California and Texas killed approximately 129 million and 300 million trees, respec- Plant Biology, University of California Davis, tively. Drought has also induced acute pine tree mortality across east-central China, Davis, CA, USA. Email: [email protected], agroover@ and across extensive areas in southwest China. Understanding the biological pro- ucdavis.edu cesses that enable trees to modify wood development to mitigate the adverse effects Funding information of drought will be crucial for the development of successful strategies for future for- USDA AFRI, Grant/Award Number: 2015- est management and conservation. 67013-22891; National Science Foundation, Grant/Award Number: 1650042; DOE Summary Office of Science, Office of Biological and Drought is a recurrent stress to forests, causing periodic forest mortality with enor- Environmental Research, Grant/Award Number: DE-SC0007183 mous economic and environmental costs. Wood is the water-conducting tissue of tree stems, and trees modify wood development to create anatomical features and hydraulic properties that can mitigate drought stress. This modification of wood de- velopment can be seen in tree rings where not only the amount of wood but also the morphology of the water-conducting cells are modified in response to environmental conditions. -
Intra-Organismal Variation in the Structure of Plant Vascular Transport Tissues in Poplar Trees
Trees (2018) 32:1335–1346 https://doi.org/10.1007/s00468-018-1714-z ORIGINAL ARTICLE Intra-organismal variation in the structure of plant vascular transport tissues in poplar trees Anna L. Jacobsen1 · Jessica Valdovinos‑Ayala1 · F. Daniela Rodriguez‑Zaccaro1 · M. Angela Hill‑Crim1 · Marta I. Percolla1 · Martin D. Venturas2 Received: 8 December 2017 / Accepted: 17 May 2018 / Published online: 24 May 2018 © Springer-Verlag GmbH Germany, part of Springer Nature 2018 Abstract Key message Phloem and xylem conduit structure vary greatly throughout the body of Populus trichocarpa trees, par- ticularly between roots and shoots. This has implications for understanding organ and whole plant vascular function. Abstract Woody plant vascular transport occurs predominantly within secondary xylem and phloem, which are both produced by the vascular cambium during secondary growth. We examined how vessel and sieve tube structure varied throughout the plant body of P. trichocarpa trees and whether xylem and phloem conduit structure was correlated across different positions within the plant. We excavated entire juvenile P. trichocarpa trees and measured vessel and sieve tube structural traits of current-year growth in 1 m increments along the main root:shoot axis. Trees were > 4 m tall and had roots that extended 4–5 m at their longest length. We found that both sieve tube and vessel diameters greatly varied throughout the plant body and with organ diameter. Roots had wider diameter conduits than shoots. Sieve tube diameter was strongly correlated with vessel diameter, which may be related to their common developmental origin. Other structural traits, such as pit membrane area and pit density for xylem, and sieve plate area and number of sieve areas per plate for phloem, also varied and were correlated with changes in conduit diameter. -
Co-Ordination of Signalling Elements in Guard Cell Ion Channel Control
Journal of Experimental Botany, Vol. 49, Special Issue, pp. 351–360, March 1998 Co-ordination of signalling elements in guard cell ion channel control A. Grabov1 and M.R. Blatt Laboratory of Plant Physiology and Biophysics, Wye College, University of London, Wye, Ashford, Kent TN25 5AH, UK Received 3 November 1997; Accepted 10 November 1997 Abstract ably important for providing a plasticity of cellular response to external and environmental stimuli. Fine regulation of solutes transport across the guard Understanding the interdependence and hierarchy of cell plasma membrane for osmotic modulation is signalling elements now presents a major challenge essential for the maintenance of the proper stomatal for research in plant biology. aperture in response to environmental stimuli. The major osmotica, K+,Cl− and malate are transported Key words: Ion channels, stomatal aperture, signalling through selective ion channels in the plasma mem- pathway, second messengers, guard cells. brane and tonoplast of guard cells. To date, a number of ion channels have been shown to operate in the guard cell plasma membrane: outwardly- and inwardly- Introduction + rectifying K channels (IK,in and IK,out), slowly- and Guard cell control of stomatal aperture is crucial to rapid-activating anion channels, and stretch-activated balancing transpiration stream and gas exchange for non-selective channels. Slow and fast vacuolar chan- photosynthesis. As transpiration and CO2 exchange can nels (SV and FV) and voltage-independent K+-selective not be regulated independently, the demand of photosyn- (VK) channels have been found at the guard cell tono- thetic machinery can lead to excessive water evaporation plast. On the molecular level, the regulation of the under adverse environmental conditions. -
Sclereid Distribution in the Leaves of Pseudotsuga Under Natural and Experimental Conditions Author(S): Khalil H
Sclereid Distribution in the Leaves of Pseudotsuga Under Natural and Experimental Conditions Author(s): Khalil H. Al-Talib and John G. Torrey Source: American Journal of Botany, Vol. 48, No. 1 (Jan., 1961), pp. 71-79 Published by: Botanical Society of America Stable URL: http://www.jstor.org/stable/2439597 . Accessed: 19/08/2011 13:16 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Botanical Society of America is collaborating with JSTOR to digitize, preserve and extend access to American Journal of Botany. http://www.jstor.org January, 1961] AL-TALIB AND TORREY-SCLEREID DISTRIBUTION 71 SMITH, G. H. 1926. Vascular anatomyof Ranalian flowers. Aquilegia formosav. truncata and Ranunculus repens. I. Ranunculaceae. Bot. Gaz. 82: 1-29. Univ. California Publ. Bot. 25: 513-648. 1928. Vascular anatomy of Ranalian flowers. II. TUCKER, SHIRLEY C. 1959. Ontogeny of the inflorescence Ranunculaceae (continued), Menispermaceae,Calycan- and the flowerin Drimys winteri v. chilensis. Univ. thaceae, Annonaceae. Bot. Gaz. 85: 152-177. California Publ. Bot. 30: 257-335. SNOW, MARY, AND R. SNOW. 1947. On the determination . 1960. Ontogeny of the floral apex of Micheiat of leaves. New Phytol. 46: 5-19. -
Redalyc.Stem and Root Anatomy of Two Species of Echinopsis
Revista Mexicana de Biodiversidad ISSN: 1870-3453 [email protected] Universidad Nacional Autónoma de México México dos Santos Garcia, Joelma; Scremin-Dias, Edna; Soffiatti, Patricia Stem and root anatomy of two species of Echinopsis (Trichocereeae: Cactaceae) Revista Mexicana de Biodiversidad, vol. 83, núm. 4, diciembre, 2012, pp. 1036-1044 Universidad Nacional Autónoma de México Distrito Federal, México Available in: http://www.redalyc.org/articulo.oa?id=42525092001 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Revista Mexicana de Biodiversidad 83: 1036-1044, 2012 DOI: 10.7550/rmb.28124 Stem and root anatomy of two species of Echinopsis (Trichocereeae: Cactaceae) Anatomía de la raíz y del tallo de dos especies de Echinopsis (Trichocereeae: Cactaceae) Joelma dos Santos Garcia1, Edna Scremin-Dias1 and Patricia Soffiatti2 1Universidade Federal de Mato Grosso do Sul, CCBS, Departamento de Biologia, Programa de Pós Graduação em Biologia Vegetal Cidade Universitária, S/N, Caixa Postal 549, CEP 79.070.900 Campo Grande, MS, Brasil. 2Universidade Federal do Paraná, SCB, Departamento de Botânica, Programa de Pós-Graduação em Botânica, Caixa Postal 19031, CEP 81.531.990 Curitiba, PR, Brasil. [email protected] Abstract. This study characterizes and compares the stem and root anatomy of Echinopsis calochlora and E. rhodotricha (Cactaceae) occurring in the Central-Western Region of Brazil, in Mato Grosso do Sul State. Three individuals of each species were collected, fixed, stored and prepared following usual anatomy techniques, for subsequent observation in light and scanning electronic microscopy. -
Tree Anatomy Stems and Branches
Tree Anatomy Series WSFNR14-13 Nov. 2014 COMPONENTSCOMPONENTS OFOF PERIDERMPERIDERM by Dr. Kim D. Coder, Professor of Tree Biology & Health Care Warnell School of Forestry & Natural Resources, University of Georgia Around tree roots, stems and branches is a complex tissue. This exterior tissue is the environmental face of a tree open to all sorts of site vulgarities. This most exterior of tissue provides trees with a measure of protection from a dry, oxidative, heat and cold extreme, sunlight drenched, injury ridden site. The exterior of a tree is both an ecological super highway and battle ground – comfort and terror. This exterior is unique in its attributes, development, and regeneration. Generically, this tissue surrounding a tree stem, branch and root is loosely called bark. The tissues of a tree, outside or more exterior to the xylem-containing core, are varied and complexly interwoven in a relatively small space. People tend to see and appreciate the volume and physical structure of tree wood and dismiss the remainder of stem, branch and root. In reality, tree life is focused within these more exterior thin tissue sets. Outside of the cambium are tissues which include transport cells, structural support cells, generation cells, and cells positioned to help, protect, and sustain other cells. All of this life is smeared over the circumference of a predominately dead physical structure. Outer Skin Periderm (jargon and antiquated term = bark) is the most external of tree tissues providing protection, water conservation, insulation, and environmental sensing. Periderm is a protective tissue generated over and beyond live conducting and non-conducting cells of the food transport system (phloem). -
Ecological Wood Adaptation and Horizontal Variations of Vessel Element and Fibre Length of Calligonum Mongolicum
Electronic Electronic Journal of Biology, 2006, Vol. 2(2): 19-23 Ecological Wood Adaptation and Horizontal Variations of Vessel Element and Fibre Length of Calligonum mongolicum Shumin Yang Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100095, China E-mail: [email protected] Abstract 2. Materials and Methods Wood anatomy of Calligonum mongolicum Turcz. Five healthy trees were felled and two discs (2-3cm was described from an ecological perspective. This thick) from each tree were taken at the height of 20- species showed similar wood structure to that 30cm above the ground. Some of the discs were species published in the same genus [1]. This immediately fixed in formalin-acetic-alcohol (5:5:90 species has distinct growth ring boundaries, ring- v/v). porosity, distinct helical thickenings, simple Wood samples were softened in 5% glycerin perforation plate, nonseptate fibre, axial solution, subsequently sectioned with a sliding parenchyma, uni- or 2-5-seriate heterogeneous rays, microtome moving on transverse, radial and and alternate intervessel pitting. It was observed tangential surfaces of the disks. Thin sections were that there is a slightly increase of fibre length as the stained with safranine, dehydrated in a graded diameter from the pith increases. However, the alcohol series and mounted in Canada balsam for vessel element length remained more or less light microscope examination. Small blocks constant from pith to bark. Furthermore, the exposing transverse, radial and tangential surfaces relationships between anatomical features and were respectively prepared according to Exley et adaptability to desert environments were discussed. al’s methods [3] for scanning electron microscope (X-650, Hitachi Ltd Tokyo, Japan) observations. -
Eudicots Monocots Stems Embryos Roots Leaf Venation Pollen Flowers
Monocots Eudicots Embryos One cotyledon Two cotyledons Leaf venation Veins Veins usually parallel usually netlike Stems Vascular tissue Vascular tissue scattered usually arranged in ring Roots Root system usually Taproot (main root) fibrous (no main root) usually present Pollen Pollen grain with Pollen grain with one opening three openings Flowers Floral organs usually Floral organs usually in in multiples of three multiples of four or five © 2014 Pearson Education, Inc. 1 Reproductive shoot (flower) Apical bud Node Internode Apical bud Shoot Vegetative shoot system Blade Leaf Petiole Axillary bud Stem Taproot Lateral Root (branch) system roots © 2014 Pearson Education, Inc. 2 © 2014 Pearson Education, Inc. 3 Storage roots Pneumatophores “Strangling” aerial roots © 2014 Pearson Education, Inc. 4 Stolon Rhizome Root Rhizomes Stolons Tubers © 2014 Pearson Education, Inc. 5 Spines Tendrils Storage leaves Stem Reproductive leaves Storage leaves © 2014 Pearson Education, Inc. 6 Dermal tissue Ground tissue Vascular tissue © 2014 Pearson Education, Inc. 7 Parenchyma cells with chloroplasts (in Elodea leaf) 60 µm (LM) © 2014 Pearson Education, Inc. 8 Collenchyma cells (in Helianthus stem) (LM) 5 µm © 2014 Pearson Education, Inc. 9 5 µm Sclereid cells (in pear) (LM) 25 µm Cell wall Fiber cells (cross section from ash tree) (LM) © 2014 Pearson Education, Inc. 10 Vessel Tracheids 100 µm Pits Tracheids and vessels (colorized SEM) Perforation plate Vessel element Vessel elements, with perforated end walls Tracheids © 2014 Pearson Education, Inc. 11 Sieve-tube elements: 3 µm longitudinal view (LM) Sieve plate Sieve-tube element (left) and companion cell: Companion cross section (TEM) cells Sieve-tube elements Plasmodesma Sieve plate 30 µm Nucleus of companion cell 15 µm Sieve-tube elements: longitudinal view Sieve plate with pores (LM) © 2014 Pearson Education, Inc.