DOCSLIB.ORG

1. Flowering Plant Structure “Roots & Shoots”

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
1. Flowering Plant Structure “Roots & Shoots” Chapters 31 & 32: Plant Structure & Reproduction 1. Flowering Plant Structure 2. Plant Reproduction & Development 1. Flowering Plant Structure “Roots & Shoots” 2 basic parts of flowering plants: shoot system • stems • leaves • flowers, fruits root system • taproot (dicots) • roots 1 Plant Tissue Types 1) Dermal tissue • outer, protective covering of the plant Dicot stem Monocot stem Vascular Vascular 2) Vascular bundle bundle Cortex tissue • transport of fluids & Pith Epidermis Epidermis structural support Xylem Vascular Phloem cylinder Key 3) Ground Epidermis Dermal tissue Ground tissue tissue Cortex Vascular tissue • everything Dicot root else! PHLOEM XYLEM Vascular Tissue High sugar concentration 1 High water pressure sugar 2 Phloem water • transports products of photosynthesis Source cell (sugars) throughout plant from sugar sources to sugar sinks • driven by osmosis, SUGAR Sink SINK increased pressure due cell to more sugar solutes near source 3 sugar 4 Xylem water • transports water & Low sugar concentration Low water pressure minerals “upward” Low water pressure (towards shoots, leaves) How is water moved “upward”? Xylem sap Water lost by Mesophyll cells Air space within leaf transpiration Stoma from leaves Outside air “pulls” water Transpiration Adhesion Cell upward wall Water through xylem molecule to replace what was lost. Xylem Cohesion, Cohesion and cells by hydrogen Flow of waterFlow of adhesion in the xylem bonding Depends on: Root hair • cohesion due Soil particle to H-bonding Water • adhesion to Water uptake from soil xylem cells 2 Leaf Structure epidermis palisade mesophyll sheath xylem spongy mesophyll phloem guard cells stomata Epidermis • outer cell layer on both sides of leaf • secrete waxy cuticle to waterproof the leaf Mesophyll (ground tissue of leaf) • loosely packed photosynthetic cells • palisade or spongy arrangement Vascular Bundles • phloem & xylem • surrounding sheath Stomata (singular = “stoma”) • openings for gas exchange, transpiration • regulated by guard cells Root Function Roots supply the plant with: CO2 • anchorage in the soil • water • mineral nutrients • oxygen (O2) • for respiration since O2 plants make ATP just as Minerals we do • over-watering can H2O suffocate a plant! 3 Importance of Nitrogen Fixation Plants require the element nitrogen in the form of + - ammonium (NH4 ) or nitrate (NO3 ) ions, however they CAN’T “fix” atmospheric nitrogen (N2) into these forms. ATMOSPHERE N2 Amino ammonium & nitrate acids, etc. N2 Nitrogen-fixing ions taken up by roots bacteria NH + H+ 4 Soil + NO – NH3 NH4 3 (nitrate) (ammonium) Nitrifying bacteria Ammonifying bacteria Organic material Root Soil bacteria and some fungi CAN fix nitrogen, thus plants depend on these microbes for useable nitrogen. Monocots vs Dicots Flowering plants are of 2 basic types: Seed Leaves Leaf veins Stems Flowers Roots MONOCOTS One Vascular bundles Floral parts Fibrous cotyledon Main veins usually parallel in complex usually in root system arrangement multiples of three DICOTS Vascular bundles Floral parts arranged in ring usually in Two multiples of Taproot cotyledons Main veins usually branched four or five usually present Monocot vs Dicot Features Cotyledons (embryonic “seed leaves”) • nourish the seedling: monocots have 1, dicots have 2 Roots • dicots have a central taproot, monocots do not Stems • dicots have a vascular structure organized into rings Leaves • monocots have narrow, smooth leaves w/parallel veins • dicots have broader leaves w/branched vein patterns Flowers • monocots – layered flower parts come in groups of 3 • dicots – layered flower parts come in groups of 4 or 5 4 2. Plant Reproduction & Development Basic Modes of Reproduction Plants reproduce in 2 basic ways: Asexually: • piece of parent plant gives rise to new plant • involves mitotic cell division only • offspring are genetically identical to parent Sexually: • fusion of haploid gametes generates offspring • offspring are genetically unique Life Cycle of Plants (sexual) • fertilization produces a zygote that develops into a diploid sporophyte • haploid spores produced by meiosis in flowers grow into multicellular haploid gametophytes, some cells of which are gametes 5 The Plant Sexual Life Cycle The sexual life cycle of plants is unique, occurring by “Alternation of Generations”: The sporophyte stage (diploid) • the plant is made of diploid cells • produces haploid spores by meiosis in the reproductive structures (e.g., flowers) The gametophyte stage (haploid) • grows from haploid spore (via mitosis) • produces gametes (sperm and/or egg) • fertilization then produces a new diploid sporophyte! Life Cycle in different Plant Phyla • gametophyte is more s prominent in p or more primitive op hy plant species g te am (2 et n) op • in more hy te advanced (n plant species, ) the sporophyte is much more prominant The Structure of Flowers reproductive organ of angiosperms 6 …more on Flower Structure Flowers have 4 main parts: Sepals • outermost structure (encloses flower bud) Petals • usually colored, inside sepals Stamen (anther & filament) • male reproductive structure • anthers produce male gametophytes (pollen grains) Carpel (stigma, style & ovary) • female reproductive structure • produces female gametophytes (embryo sacs) Fertilization in Angiosperms • pollen grains adhere to the stigma (pollination) • tube cell in pollen elongates down style to penetrate ovule in ovary • 2 sperm are released to fertilize the egg & fuse with a special diploid cell in ovule Seed Production endosperm = nutrients for plant embryo • zygote develops into embryo, triploid cell forms endosperm • seed coat derived fr. ovule wall encloses embryo, endosperm • fruit develops from ovary wall to aid seed dispersal 7 Seed Dispersal Seeds can be dispersed via fruits by: Water • floating on water (e.g., coconuts) Air • lightweight seeds can be transported by the wind (e.g., dandelion, maple) Animal • edible fruits entice animals to eat them • “hitchhiker” fruits stick to animals Plant Growth Plant growth occurs in 2 basic ways: Terminal bud Primary growth • growth in length of roots & shoots • due to special “stem cell” tissue called Axillary buds apical meristem Secondary growth • growth in width due Arrows = to lateral meristem direction of growth • occurs in “woody” Root tips perennial plants o Apical Leaves Primary (1 ) Growth meristem Vascular cylinder Cortex Root hair Epidermis Zone of maturation 1o Root Growth Zone of elongation Axillary bud × meristems LM 103 1 o 2 Zone of 1 Shoot cell division Apical Growth meristem region Key Root Dermal tissue system cap Ground tissue system Vascular tissue system 8 Secondary (2o) Growth Due to lateral meristem tissue which consists of: Vascular Cambium (new phloem & xylem) Cork Cambium (cork replaces the epidermis during 2o growth) Year 1 Year 1 Year 2 Early Spring Late Summer Late Summer Key Dermal tissue system Ground tissue system Vascular tissue system Shed epidermis wth wth wth Gro Gro Gro Primary xylem Epidermis Secondary Cork Vascular xylem Cortex Cork Secondary xylem cambium (wood) cambium Bark (2 years’ growth) Primary phloem Secondary phloem Secondary Growth in Woody Plants Vascular cambium produces new phloem & xylem ea yr: • spring & summer growth look diff., producing an annual ring Sapwood Rings Wood rays Heartwood Sapwood Vascular cambium Secondary phloem Heartwood Bark Cork cambium Cork Heartwood Sapwood • old, dead xylem from • new, functioning xylem previous years from most recent 2o growth Key Terms for Chapters 31 & 32 • mesophyll, stomata, phloem, xylem • asexual vs sexual, “alternation of generations” • sporophyte, gametophyte • sepal, petal • stamen – anther & filament (pollen, tube cell) • carpel – stigma, style, ovary (ovule, embryo sac) • monocot, dicot Relevant Review Questions: Ch. 31 – 2-4, 6-11 Ch. 32 – 1, 3 9.
Load more

Recommended publications
  • Plant Terminology
    PLANT TERMINOLOGY Plant terminology for the identification of plants is a necessary evil in order to be more exact, to cut down on lengthy descriptions, and of course to use the more professional texts. I have tried to keep the terminology in the database fairly simple but there is no choice in using many descriptive terms. The following slides deal with the most commonly used terms (more specialized terms are given in family descriptions where needed). Professional texts vary from fairly friendly to down-right difficult in their use of terminology. Do not be dismayed if a plant or plant part does not seem to fit any given term, or that some terms seem to be vague or have more than one definition – that’s life. In addition this subject has deep historical roots and plant terminology has evolved with the science although some authors have not. There are many texts that define and illustrate plant terminology – I use Plant Identification Terminology, An illustrated Glossary by Harris and Harris (see CREDITS) and others. Most plant books have at least some terms defined. To really begin to appreciate the diversity of plants, a good text on plant systematics or Classification is a necessity. PLANT TERMS - Typical Plant - Introduction [V. Max Brown] Plant Shoot System of Plant – stem, leaves and flowers. This is the photosynthetic part of the plant using CO2 (from the air) and light to produce food which is used by the plant and stored in the Root System. The shoot system is also the reproductive part of the plant forming flowers (highly modified leaves); however some plants also have forms of asexual reproduction The stem is composed of Nodes (points of origin for leaves and branches) and Internodes Root System of Plant – supports the plant, stores food and uptakes water and minerals used in the shoot System PLANT TERMS - Typical Perfect Flower [V.
    [Show full text]
  • Studies on Seed Germination, Seedling Growth, and in Vitro Shoot
    HORTSCIENCE 44(3):751–756. 2009. plantlets are detached from the mother plant that are dried and planted. However, seed propagation is more feasible and recommen- Studies on Seed Germination, Seedling ded for survival of rare species (Van Wyk and Smith, 1996). If this species has to be Growth, and In Vitro Shoot Induction propagated on a large scale by means of seed or tissue culture methods, then currently there of Aloe ferox Mill., a Commercially is no basic information available on these aspects. Aloes are succulent and warm-cli- mate plants, where both temperature and Important Species water play an important role in establishing Michael W. Bairu, Manoj G. Kulkarni, Rene´e A. Street, Rofhiwa them. This study was therefore conducted to B. Mulaudzi, and Johannes Van Staden1 examine 1) the effects of different temper- atures, growth-promoting substances, and Research Centre for Plant Growth and Development, School of Biological watering frequencies on seed germination and Conservation Sciences, University of KwaZulu-Natal Pietermaritzburg, and seedling growth of A. ferox; and 2) to Private Bag X01, Scottsville 3209, South Africa assess the applicability of an in vitro propa- gation protocol developed for other Aloe spp. Additional index words. cytokinins, growth regulators, multiplication rate, smoke solutions, temperature, tissue culture Materials and Methods Abstract. A study was done to investigate the effects of some physical and chemical factors on growth and development of Aloe ferox ex vitro and in vitro. The effects of light, Seed collection. Dried seeds of A. ferox temperature, and smoke–water on seed germination, ex vitro seedling growth require- were collected between the middle to the end ments, and effect of germination medium and cytokinins on shoot induction and of August from the Botanical Garden, Uni- multiplication in vitro were investigated.
    [Show full text]
  • Chapter 5: the Shoot System I: the Stem
    Chapter 5 The Shoot System I: The Stem THE FUNCTIONS AND ORGANIZATION OF THE SHOOT SYSTEM PRIMARY GROWTH AND STEM ANATOMY Primary Tissues of Dicot Stems Develop from the Primary Meristems The Distribution of the Primary Vascular Bundles Depends on the Position of Leaves Primary Growth Differs in Monocot and Dicot Stems SECONDARY GROWTH AND THE ANATOMY OF WOOD Secondary Xylem and Phloem Develop from Vascular Cambium Wood Is Composed of Secondary Xylem Gymnosperm Wood Differs from Angiosperm Wood Bark Is Composed of Secondary Phloem and Periderm Buds Are Compressed Branches Waiting to Elongate Some Monocot Stems Have Secondary Growth STEM MODIFICATIONS FOR SPECIAL FUNCTIONS THE ECONOMIC VALUE OF WOODY STEMS SUMMARY ECONOMIC BOTANY: How Do You Make A Barrel? 1 KEY CONCEPTS 1. The shoot system is composed of the stem and its lateral appendages: leaves, buds, and flowers. Leaves are arranged in different patterns (phyllotaxis): alternate, opposite, whorled, and spiral. 2. Stems provide support to the leaves, buds, and flowers. They conduct water and nutrients and produce new cells in meristems (shoot apical meristem, primary and secondary meristems). 3. Dicot stems and monocot stems are usually different. Dicot stems tend to have vascular bundles distributed in a ring, whereas in monocot stems they tend to be scattered. 4. Stems are composed of the following: epidermis, cortex and pith, xylem and phloem, and periderm. 5. Secondary xylem is formed by the division of cells in the vascular cambium and is called wood. The bark is composed of all of the tissues outside the vascular cambium, including the periderm (formed from cork cambium) and the secondary phloem.
    [Show full text]
  • Auxins for Hardwood Cuttings: Effect of Root-Promoting Hormones
    Auxins for Hardwood Cuttings effect of root-promoting hormones in propagating fruit trees by hardwood cuttings studied during past three seasons H. T. Hartmann Hardwood cuttings of five species of fruit trees, Marianna 2624 plum, Angers quince, Stockton Morello cherry, Mal- ling-Merton 793 apple, and Mission olive, were used in propagation tests to study the effects of various root-promot- ing hormones-auxins-applied under several different conditions. Marianna 2624 plum is a commonly used rootstock for a number of the stone fruit species; the 2624 selection is a seedling of the parent Marianna plum, presumably an open-pollinated cross of Prunus cerasifera and P. munsoniana. This rootstock is propagated commer- cially by hardwood cuttings, but in heavy soils considerable difficulty is often experienced in obtaining satisfac- tory rooting. Angers quince4ydonia oblong- has long been used as a dwarfing root- stock for certain of the pear varieties. It is commercially propagated by hard- wood cuttings. Stockton Morello cherry-Prunus cer- asus-is used to a considerable extent in California as a semidwarfing rootstock for the sweet cherry and is propagated commercially by suckers arising around the base of older trees. It would be de- sirable to be able to propagate this stock by cuttings. In all the tests conducted with this variety, however, not one hard- wood cutting was induced to root. Later studies have shown that it can be easily rooted under mist humidification by softwood cuttings taken from actively growing shoots if treated with indolebu- tyric acid. The Malling-Merton 793 apple-Ma- lus sylwstris-is a newly developed clonal apple rootstock from’ England which is usually propagated by some method of layering.
    [Show full text]
  • The Effects of Different Hormones and Their Doses on Rooting of Stem Cuttings in Anatolian Sage (Salvia Fruticosa Mill.)
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Available online at www.sciencedirect.com ScienceDirect APCBEE Procedia 8 ( 2014 ) 348 – 353 2013 4th International Conference on Agriculture and Animal Science (CAAS 2013) 2013 3rd International Conference on Asia Agriculture and Animal (ICAAA 2013) The Effects of Different Hormones and Their Doses on Rooting of Stem Cuttings in Anatolian Sage (Salvia Fruticosa Mill.) A.Canan SAĞLAM a,*, Seviye YAVERa, İsmet BAŞERa, Latif CİNKILIÇb, aNamık Kemal Üniversitesi Ziraat Fakültesi Tarla Bitkileri Bölümü, Tekirdağ bNamık Kemal Üniversitesi Çorlu meslek Yüksek Okulu, Tekirdağ Abstract In this research, three different hormones and five different hormone dosages were applied on cuttings were taken from Anatolian sage plants (Salvia fruticosa Mill.) before flowering period. NAA, IBA (0, 60, 120, 180, 240 ppm) and IAA hormones (0, 100, 200, 300, 400 ppm) were prepared by dissolving in distilled water. Stem cuttings were kept in hormone solution for 24 hours and they were planted in perlit medium under greenhouse conditions. After a month, the number of rooted stem cutting, the number of root per stem cuttings, root length and root weight were determined on stem cuttings. Rooting was observed in all of the cuttings for both samples to which hormone was applied and to which hormone was not applied. According to the result of the variance analysis, the effects of the hormones and hormone doses on the examined characters were found significant as statistically. According to the results obtained, IAA application increased root number considerably. While high hormone dose applications caused the notable increase in root weight and root number in all of three hormones, low hormone applications did not affect root length.
    [Show full text]
  • Plant Pathology
    Plant Pathology 330-1 Reading / Reference Materials CSU Extension Fact Sheets o Aspen and poplar leaf spots – #2.920 o Backyard orchard: apples and pears [pest management] – #2.800 o Backyard orchard: stone fruits [pest management] – #2.804 o Bacterial wetwood – #2.910 o Cytospora canker – #2.937 o Diseases of roses in Colorado – #2.946 o Dollar spot disease of turfgrass – #2.933 o Dutch elm disease – #5.506 o Dwarf mistletoe management – #2.925 o Fairy ring in turfgrass – #2.908 o Fire blight – #2.907 o Forest fire – Insects and diseases associated with forest fires – #6.309 o Friendly pesticides for home gardens – #2.945 o Greenhouse plant viruses (TSWV-INSV) – #2.947 o Honeylocust diseases – #2.939 o Juniper-hawthorn rust – #2.904 o Juniper-hawthorn rust – #2.904 o Leaf spot and melting out diseases – #2.909 o Necrotic ring spot in turfgrass – #2.900 o Non-chemical disease control – #2.903 o Pesticides – Friendly pesticides for home gardens – #2.945 o Pinyon pine insects and diseases – #2.948 o Powdery mildew – #2.902 o Roses – Diseases of roses in Colorado – #2.946 o Russian olive decline and gummosis – #2.942 o Strawberry diseases – #2.931 o Sycamore anthracnose – #2.930 CSU Extension Publications o Insects and diseases of woody plants of the central Rockies – 506A Curriculum developed by Mary Small, CSU Extension, Jefferson County • Colorado State University, U.S. Department of Agriculture and Colorado counties cooperating. • CSU Extension programs are available to all without discrimination. • No endorsement of products named is intended, nor is criticism implied of products not mentioned.
    [Show full text]
  • Principal Types of Vegetative Shoot Apex Organization in Vascular Plants1
    PRINCIPAL TYPES OF VEGETATIVE SHOOT APEX ORGANIZATION IN VASCULAR PLANTS1 RICHARD A. POPHAM Department of Botany and Plant Pathology, The Ohio State University, Columbus 10 Before progress can be made in research, a problem must be recognized. Once the problem has been perceived, a research program may be directed toward a solution. The problem of how and where a shoot grows and the organization of the shoot apex was apparently first conceived by Kaspar Friedrich Wolff (1759). Although his observations on the structure, formation, and growth of cells were fantastically inaccurate, he made a great contribution to our knowledge of the growing plant by setting forth a new and important problem. In a very real sense, Wolff is the father of developmental plant anatomy. Disagreement is the life blood of many research problems. Strenuous opposition is often engendered by a dogmatic statement or a theory which is proposed as a universal truth. Opposition to Wolff's (1759) original proposition regarding the organization and growth of shoot apices prompted plant anatomists, some 85 years later, to investigate the truth of the statement. The factual solution of the problem of shoot apex organization had its beginnings in the work of Nageli (1845). Following this work on many lower cryptogams, Nageli concluded that the cells of all tissues of the shoot of cryptogams and higher plants have their genesis in a single apical cell. The new-born apical cell theory supported by Hofmeister (1851) and others provided the impetus for a renewed, vigorous attack on the problem of shoot apex organization. A little later a new proposal, Hanstein's (1868) histogen theory was born of more careful observations and in a mind unfettered by the prevailing fanaticism of the apical cell theorists.
    [Show full text]
  • Rooting Hormones
    Essential Factor: Rooting Hormones Rooting Hormones are auxins, or plant growth regulators, that are involved in cell elongation and adventitious root formation. ¡ Reasons to use rooting hormones in your facility ¡ Difficult or slow to root crops can benefit greatly from rooting hormone application. ¡ Uniformity and speed of rooting can be increased when properly utilized, even for crops that normally root easily. ¡ Overhead applications can be made after crop is in the greenhouse to improve efficiency. ¡ Any resource or tool that you can use to decrease the time the cutting spends under mist should be considered a valuable part of a propagators tool box. Rooting Hormones: Basal end applications Powder Applications Liquid Applications ¡ Powdered hormone such as ¡ IBA can be applied as a liquid Rhizopon AA Dry Powder can basal application with typical be applied to basal end of the rates of 500-1000ppm. cutting. ¡ Dip N Grow and Rhizopon AA are ¡ Use a duster to apply to the stem only. two commonly used hormones for this type of application. ¡ Avoid getting powdered hormone on the leaves. ¡ Apply to the basal end with a hand-held spray bottle. ¡ Do not dip the stem into a container of hormone….this is a ¡ Do not allow solution to get on the sanitation risk. stems or leaves of the cutting. ¡ Do not coat the stem with a ¡ Do not dip stems directly into the solid layer of powder. solution…..this is a sanitation risk. Rooting Hormone Trial: Pretreated White Lightning Osteo ¡ Osteospermum White Lightning was pre-treated at Las Limas Top row pretreated with 1,500ppm Dip-N-Grow as a Bottom row untreated basal dip.
    [Show full text]
  • Common Rooting Hormones Methods of Auxin Application Benefits of Root-Promoting Compounds
    COMMON ROOTING HORMONES METHODS OF AUXIN APPLICATION BENEFITS OF ROOT-PROMOTING COMPOUNDS In this lab, you will be introduced to common rooting hormones that we will be using throughout the plant propagation course. You will also be introduced to several methods of auxin application. There are four primary reasons for treating cuttings with root-promoting compounds. These compounds can increase the percentage of cuttings which form roots, reduce the time to root initiation, increase the number of roots produced per cutting, and increase the uniformity of rooting Compounds commonly used to promote rooting include indoleacetic acid, indolebutyric acid, napthaleneacetic acid and a number of phenoxy compounds. IAA is a naturally occurring auxin but is not widely used because it is readily metabolized into inactive forms by plant tissue. IBA is the most widely used form of auxin in propagation. NAA is a synthetic auxin and phenoxy compounds are used primarily as herbicides but can also be used as sources of auxin. Rooting compounds are available in either the pure chemical form or as commercial preparations. Pure crystals of reagent grade chemical can be purchased from a chemical supply company and must be diluted. Acid forms of pure auxin are not water soluble, so K-formulations of IBA and NAA are often preferable due to their solubility in water. Commercial preparations are either dissolved in a solvent or dispersed in talc. Some of these preparations also contain a fungicide such as thiram. There are 4 general application methods for auxins. • In the talcum powder application, the bases of cuttings are dipped directly in the talcum powder based hormone just prior to sticking the cutting.
    [Show full text]
  • Better Root Systems with Gravel Beds
    Better Root Systems with Gravel Beds Eric Kuehler Science Delivery / Technology Specialist USDA Forest Service [email protected] After natural disaster, restoring tree canopy cover is often desired. Or sustainably replacing trees in cities after older trees are removed may be the objective. Maintaining a gravel bed for tree planting stock is inexpensive and allows a city to put more trees in the ground compared to B&B or containerized trees. Tree planting can be expensive Image courtesy of Deeproot A.M. Leonard Horticultural Tool and Supply Co. • Large trees are heavy • Expensive • Need heavy equipment and labor to move them • Added costs on top of cost of tree • Can’t use volunteers for this work Planting bare-root trees is much less expensive • Tree stock is much less expensive • Smaller trees without the soil • Lighter for volunteers • No heavy equipment needed (hand dug holes) • Easier to plant trees at proper depth What is a Gravel Bed? Increase fibrous root volume for out-planting Irrigated bed of gravel 6 – 9 months of grow time for tree growth • Concept developed by Chris Starbuck at University of Missouri • Extends the bare-root tree planting window to year round How does it work? Hydroponics Gravel = Macropores It can be a raised bed or belowground Advantages • Inexpensive • Trees • Bedding materials • Reusable • Low maintenance • Extends tree planting window • Year round planting • Grows abundant fibrous roots • Reduces transplant shock • Ensures proper planting depth and root orientation • Bare-root tree stock is generally
    [Show full text]
  • Red Shoot Disease of Cranberry
    Cranberry Pest Management Red Shoot Disease of Cranberry Red shoot, caused by the fungus Symptoms and spindly with red or yellow Exobasidium perenne, is a rela- leaves that are slightly more tively minor disease of the culti- Signs round than typical oblong cran- vated American cranberry Symptoms Þrst appear in the berry leaves (Figures 1Ð3). By (Vaccinium macrocarpon) and the spring on current yearÕs shoots mid summer the lower surfaces wild small cranberry (Vaccinium that occur singly or as a cluster of leaves become covered with oxycoccus). The red shoot fun- arising from a node on a buried white, powdery fungal spores. gus is related to the fungus that runner. Affected shoots do not Shoots wither after the fungus causes red leaf spot. Red shoot produce ßowers but rather are has shed its spores. Diseased has been reported in Wisconsin, shoots break off easily from the Massachusetts, the PaciÞc Northwest, and in the Atlantic maritime provinces of Canada. Red shoot is not an economi- cally important disease, and speciÞc control recommenda- tions have not been developed. However, the distorted, red or yellow shoots have sometimes been misidentiÞed as a weed, making growers think that an herbicide should be applied. The fact that red shoot is a dis- ease has been conÞrmed by tak- ing fungal spores from infected plants and inoculating them Figure1. Clusters of red shoot in a bed of ‘Searles’. The orangish-rust col- onto healthy plants; the inocu- ored shoots to the left are not affected by red shoot, but rather a different lated plants then developed red problem such as upright dieback.
    [Show full text]
  • Vegetative Vs. Reproductive Morphology
    Today’s lecture: plant morphology Vegetative vs. reproductive morphology Vegetative morphology Growth, development, photosynthesis, support Not involved in sexual reproduction Reproductive morphology Sexual reproduction Vegetative morphology: seeds Seed = a dormant young plant in which development is arrested. Cotyledon (seed leaf) = leaf developed at the first node of the embryonic stem; present in the seed prior to germination. Vegetative morphology: roots Water and mineral uptake radicle primary roots stem secondary roots taproot fibrous roots adventitious roots Vegetative morphology: roots Modified roots Symbiosis/parasitism Food storage stem secondary roots Increase nutrient Allow dormancy adventitious roots availability Facilitate vegetative spread Vegetative morphology: stems plumule primary shoot Support, vertical elongation apical bud node internode leaf lateral (axillary) bud lateral shoot stipule Vegetative morphology: stems Vascular tissue = specialized cells transporting water and nutrients Secondary growth = vascular cell division, resulting in increased girth Vegetative morphology: stems Secondary growth = vascular cell division, resulting in increased girth Vegetative morphology: stems Modified stems Asexual (vegetative) reproduction Stolon: above ground Rhizome: below ground Stems elongating laterally, producing adventitious roots and lateral shoots Vegetative morphology: stems Modified stems Food storage Bulb: leaves are storage organs Corm: stem is storage organ Stems not elongating, packed with carbohydrates Vegetative
    [Show full text]