DOCSLIB.ORG

Rusts and Smuts Maydis and Cochliobolus Heterostrophus

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Rusts and Smuts Maydis and Cochliobolus Heterostrophus Southern Corn Leaf Blight 1. In 1970 disease resulted in loss of corn crop in the order of billions of dollars. 2. Disease organism: Helminthosporium maydis (=Bipolaris maydis, Drechslera Rusts and Smuts maydis and Cochliobolus heterostrophus. 3. Problems that made disease so deadly were similar to those of Late Blight of Potato. 4. Topic for paper in class? Rusts and Smuts Rusts z Introduction 1. Pathogenic on a variety of seed 1. Two of the most economically plants and some ferns. important group of fungi in 2. Species pathogenic to grains Basidiomycota. historically well known. Reliably 2. Rust probably known since reported on grains as far back as beginning of agriculture: 3000 years. Rusts recorded in Bible (Blast). 3. Common name is based on “rusty” Reported by Greeks and Romans. colored blotches on stems and Robigus and Robigalia of Rome. leaves of plants from urediospore 3. Smut not specifically mentioned stage. until around 1700 by Jethro Tull. Rusts 1. Pathogenic on a variety of seed plants and some ferns. 2. Obligate parasites and of significant economic importance when on grains. 3. First described by Theophrastus on grains in Historia Plantarum. 4. Actual cause of disease would not be known until mid 1800s. 1 Rusts Rusts 7. Spore stages of Puccinia graminis: 5. Life history of rusts is unique. Stage 0: Spermogonium. Produces Up to five spore stages. spermatia and receptive hyphae. Can have two hosts. Stage I: Aeciums produce No fruitbody, e.g mushroom, like aeciospores. other Basidiomycota. Stage II: Uredium produce 6. Will use Puccinia graminis as urediospores. example of a Wheat Rust. Stage III: Telium produce teliospores. Stage IV: Basidium produce basidiospores. Rusts Rusts 8. Normally presented in this order: 9. Has two hosts: Wheat and alternate Stage II: Uredium produce hosts Barberry. urediospores. Urediospores and teliospores Stage III: Telium produce occur on Wheat. teliospores. Spermogonium and aeciospores Stage IV: Basidium produce occur on Barberry. basidiospores. Basidiospores transitional, infects Stage 0: Spermogonium. Produces Barberry. spermatia and pycniospores. 10.Fungus gains entrance to host Stage I: Aeciums produce through stomata. aeciospores. Urediospores Ruptured Epidermis Stoma Early spring, aeciospore infects wheat to start infection. 2 11.Spore stage gives plant its characteristic rusty color 12.Urediospore stage is “repeater stage”. 13.Late summer, prior to fall, uredium Continually re- converts to telium and produce infects wheat into teliospores. late summer 14.Teliospore thick-walled, with two cells and black. Basidium 15.Teliospore over winters. Basidiospores 16.Following spring, germinates to produce basidia and basidiospores. Rusts 17.Basidiospore must go to Barberry. Produces spermogonium on upper surface of leaf. Spermogonium consists of receptive hyphae (female) and spermatia (male). Each spermogonium has a sweet sugary droplet. Barberry plant 3 Receptive Spermogonia hyphae with sugary exudates Spermatia Clusters of spermogonia on upper surface 18.Spermogonium with receptive hyphae of Barberry leaf (note exudates). and spermatia. Rusts 18.Flies necessary to continue life cycle. Flies visit spermogonia for sugar solution. Takes spermatia to receptive hyphae as it visits spermogonia. Flies responsible for completion of sexual cycle. Rusts 21.Aeciospore must go now to Wheat and cycle starts over. On lower surface of Barberry, aecium with aeciospores formed. 4 Summary of Wheat Rusts Wheat Rusts 1. Wheat Rusts believed to be responsible for first famine. 2. Recorded in Bible. 1800 years before birth of Christ. Story of Joseph tells of incident. 3. Recorded during Roman Empire. Rome was plagued by Wheat Rust. Wheat Rusts Wheat Rusts 4. Cato, The Elder, suggested 3. Recorded during Roman Empire planting wheat away from foggy, (continue). misty areas. Romans created a god, Robigus, Shortly after birth of Christ, for the rust god. 300 years, weather changed and Every spring, on April 25th., became wetter and cooler. Robigalia held honoring Robigus Greater problems with Wheat for 700 years. Rust occurred causing famine, hunger, diseases and discontent. Internal problems from within contributed to decline of Roman Empire. Wheat Rusts Wheat Rusts 5. How Wheat Rust spread was 8. Although cause of disease was unknown. unknown, by 1600, in France, it 6. Barberry became a popular plant was realized that Barberry’s for its foliage and tasty berries, presence was somehow connected which spread the disease. with Wheat Rust. 7. Now known that you cannot 9. Law soon passed to eradicate successfully grow wheat with Barberry in Europe. Barberry present. 10. Wheat was first introduced to In 1920, a circular area of 10 New World in early 1500s and miles, Wheat crop was virtually Wheat Rust came with wheat. destroyed due to one Barberry plant. 5 Wheat Rusts Wheat Rusts 11. By 1726, first Barberry 11. Still a problem: eradication law enacted and still a. New strain discovered in Africa and one of means used to control Asia. Wheat Rusts. 12.Never successfully controlled b. Destroyed wheat crops in Uganda, Wheat Rust in North America by Kenya and Ethiopia, and is spreading. eradication of Barberry. Why? c. Eventually will spread to Saudi Arabia, Egypt and all of Middle Eastern 13. Breeding resistant of wheat, in countries and cause mass starvation. 1960’s, somewhat successful. d. Will take about 6-8 years to develop new resistant wheat strain. Coffee Rusts Coffee Rusts 1. Origin of coffee is unknown, but 4. By 1700, 3000 coffee houses in many stories told of its origin. London. 2. Believed to be native to Africa Merchant, lawyers and business and early on introduced to Arabia. men gathered for discussion. 3. First introduced into Europe, via Businesses began, e.g., Lloyds of Venice, in 1615, then France, in London, started in coffee house in 1640, and England, in 1650. 1690. Water was often contaminated. Coffee Rusts Coffee Rusts 5. Price became higher with 6. British planted coffee on all popularity. suitable land in Sri Lanka by 1825. Arabian city, Mocha, had monopoly 7. 1875, Coffee Rust, Hemileia on coffee. castatrix struck. Monopoly ended by 1690. Berkeley had recorded disease in Plantations first started in Java, 1869. then Ceylon (Sri Lanka), Sumatra Suggested immediate action be and then in the New World. taken against disease. By 1875, the fungus had spread to all coffee plantations. 6 Coffee Rusts Coffee Rusts 7. 1875, Coffee Rust, Hemileia 7. 1875, Coffee Rust, Hemileia castatrix struck (continue). castatrix struck (continue). Sulfur solution spray was tried, British gave up on coffee and but unsuccessfully. began growing tea in Sri Lanka. A remedy for disease has never Reason why Indian Tea is main been found. stimulant consumed by British. Coffee Rust eventually destroyed all coffee plants in Sri Lanka, Java Coffee now mostly grown in New and Sumatra and eventually to World and was free of Coffee Arabia, Liberia and Africa. Rust until 1970. Coffee Rusts 8. Still not an effective means of treating Coffee Rusts. Breeding programs have produced resistant varieties, but poorer in Smuts “quality”. Introduction Introduction z Smut, in literal sense, mean dirt z First mention of smut in 1700 by or excrement. English agriculturalist Jethro Tull. z Presently, we use it to mean z Because of widespread occurrence on something that is filthy and grains, probably observed since obscene. beginning of agriculture. z This group of fungi is somewhat like the rusts. z Reference to rusts in some instances Both are classified in Basidiomycota. may actually have been smuts. Do not have fruiting bodies and basidia and basidiospores produced by teliospores. 7 Mathieu Tillet Mathieu Tillet z Keeper of mint, in France, by profession. z In 1755, studied smut on Wheat and determined two types of smuts were produced. Le Carie, Common Bunt or Stinking Smut. Contaminated grain filled with “black, foul smelling powder”. Le Charbon, Loose Smut. Plant is Common Bunt or Loose Smut covered with black powder that is Stinking Smut readily blown away by wind. Mathieu Tillet Mathieu Tillet z In 1847, this distinction would z Regardless of soil type, when, be verified by Charles and Louis and different weather Tulasne. conditions, contaminated wheat z In order to honor Tillet, they gave rise to contaminated plants. described Stinking Smut as a new z Concluded this meant that “black genus, Tilletia, after Tillet. powder” in seeds responsible for Species was named Tilletia caries. smutted plants, i.e. seed borne. z z Tillet tried to demonstrate that the Also washed seeds before planting in smutted plants were caused by the cattle urine, water and lye black powdery material in the grain. suppressed disease to some degree. Bénédict Prévost Bénédict Prévost z This line of research did z Thought sprout penetrated soft eventually lead to eliminating tissue of Wheat and destroyed stinking smut from Wheat. the seed. z About 50 years later, Prévost z Accidentally discovered means of continued with concept of washing controlling Stinking Smut. seeds to rid Wheat of smut. z Spores did not readily germinate in z Also observed germination of spores, distilled water as they did in well which had previously not been seen. water. z Saw germination of “stubby sprouts” z Germinated spores in distilled water growing from spores. grew several hours and then died. 8 Bénédict Prévost Bénédict Prévost z Observation, however, was z Farmers slow to follow, but impractical. from 1850-1900 was z Accidentally discovered significance extensively used. of observation. z Later other solutions used: z Experiments with copper sulfate Formaldehyde indicated that smut could be Several mercury compounds. destroyed even with trace amounts of copper. Most recently hexachlorobenzene (=HCB). z In 1807 recommended washing seeds with copper sulfate. z Method=topical chemotherapy Loose Smut Origin of Gingerbread z Topical chemotherapy not z What do you do with flour made from effective against Loose Smut. smutted wheat?. Disease systemic Odor, taste and appearance of bread Most solutions tried also killed made from such flour undesirable.
Load more

Recommended publications
  • Ustilago: Habitat, Symptoms and Reproduction | Teliomycetes
    Ustilago: Habitat, Symptoms and Reproduction | Teliomycetes For B.Sc. Botany 1st By Dr. Meenu Gupta Assistant Professor Botany J.D.W.C. Patna 1. Habit and Habitat of Ustilago: Ustilago, the largest genus of the family Ustilaginaceae is represented by more than 400 cosmopolitan species. Butler and Bisby (1958) reported 108 species from India. All species are parasitic and infect the floral parts of wheat, barley, oat, maize, sugarcane, Bajra, rye and wild grasses. The name Ustilago has been derived from a Latin word ustus meaning ‘burnt’ because the members of the genus produce black, sooty powdery mass of spores on the host plant parts imparting them a ‘burnt’ appearance. This black dusty mass of spores resembles soot or smut, therefore, commonly it is also known as smut fungus. The fungus is of much economic importance, because it causes heavy loss to various economically important plants. This genus is very common in U.P., Bihar, Punjab and Madhya Pradesh. 2. Symptoms of Ustilago: The symptoms appear only on the floral parts. The floral spikes turn black and remain filled with the smut spores. Ustilago produces two main types of symptoms: 1. The blackish powder of spores is easily blown away by the wind, leaving a bare stalk of inflorescence (Fig. 1 B). Species showing such symptoms are called loose smuts e.g., (a) Loose smut of oat caused by U. avenae (b) Loose smut of barley caused by U. nuda (c) Loose smut of wheat caused by U. nuda var. tritici. (Fig. 13A, B). (d) Loose smut of doob grass caused by U.
    [Show full text]
  • Four Master Teachers Who Fostered American Turn-Of-The-(20<Sup>TH
    MYCOTAXON ISSN (print) 0093-4666 (online) 2154-8889 Mycotaxon, Ltd. ©2021 January–March 2021—Volume 136, pp. 1–58 https://doi.org/10.5248/136.1 Four master teachers who fostered American turn-of-the-(20TH)-century mycology and plant pathology Ronald H. Petersen Department of Ecology & Evolutionary Biology, University of Tennessee Knoxville, TN 37919-1100 Correspondence to: [email protected] Abstract—The Morrill Act of 1862 afforded the US states the opportunity to found state colleges with agriculture as part of their mission—the so-called “land-grant colleges.” The Hatch Act of 1887 gave the same opportunity for agricultural experiment stations as functions of the land-grant colleges, and the “third Morrill Act” (the Smith-Lever Act) of 1914 added an extension dimension to the experiment stations. Overall, the end of the 19th century and the first quarter of the 20th was a time for growing appreciation for, and growth of institutional education in the natural sciences, especially botany and its specialties, mycology, and phytopathology. This paper outlines a particular genealogy of mycologists and plant pathologists representative of this era. Professor Albert Nelson Prentiss, first of Michigan State then of Cornell, Professor William Russel Dudley of Cornell and Stanford, Professor Mason Blanchard Thomas of Wabash College, and Professor Herbert Hice Whetzel of Cornell Plant Pathology were major players in the scenario. The supporting cast, the students selected, trained, and guided by these men, was legion, a few of whom are briefly traced here. Key words—“New Botany,” European influence, agrarian roots Chapter 1. Introduction When Dr. Lexemual R.
    [Show full text]
  • Corn Smuts, RPD No
    report on RPD No. 203 PLANT February 1990 DEPARTMENT OF CROP SCIENCES DISEASE UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN CORN SMUTS Corn smuts occur throughout the world. Common corn smut, caused by the fungus Ustilago zeae (synonym U. maydis), and head smut, caused by the fungus Sporisorium holci-sorghi (synonyms Sphacelotheca reiliana, Sorosporium reilianum and Sporisorium reilianum), are spectacular in appearance and easily distinguished. Common smut occurs worldwide wherever corn (maize) is grown, by presence of large conspicuous galls or replacement of grain kernels with smut sori. The quality of the remaining yield is often reduced by the presence of black smut spores on the surface of healthy kernels. COMMON SMUT Common smut is well known to all Illinois growers. The fungus attacks only corn–field corn (dent and flint), Indian or ornamental corn, popcorn, and sweet corn–and the closely related teosinte (Zea mays subsp. mexicana) but is most destructive to sweet corn. The smut is most prevalent on young, actively growing plants that have Figure 1. Infection of common corn smut been injured by detasseling in seed fields, hail, blowing soil or and on the ear. Smut galls are covered by the particles, insects, “buggy-whipping”, and by cultivation or spraying silvery white membrane. equipment. Corn smut differs from other cereal smuts in that any part of the plant above ground may be attacked, from the seedling stage to maturity. Losses from common smut are highly variable and rather difficult to measure, ranging from a trace up to 10 percent or more in localized areas. In rare cases, the loss in a particular field of sweet corn may approach 100 percent.
    [Show full text]
  • CONTROL of SMUT in WHEAT and OTHER SMALL GRAINS by H
    Bulletin No. 116 June, 1931 Montana State College, Extension Service, J. C. Taylor, Director, Cooperative Extension Work in Agriculture and Home Economics. Montana State College and Uni~ed States Department of Agriculture, co-operating. Distributed in furtherance of the Acts of Congress ~ay 8 and June 30, 1.914. ~ CONTROL OF SMUT IN WHEAT AND OTHER SMALL GRAINS By H. E. Morris, Extension Plant Pathologist Waldo Kidder, Extension Agronomist Smuts cost the farmers of Montana many thousands of dollars each year. In 1930, stinking smut of wheat alone caused a loss of approximately $750;000, due to decreased yields and to a lower price per bushel. This loss and also that due to the smuts {..:Fig. 1. Smutted and normal heads of wheat. The head at the left ,is a typi:cal head affected with covered or stinking smut, The next, head IS a he'althy head. The two heads on the right show two stages of the loose smut in wheat. (-Courtesy,D. S. Dept. of Agr.) . ,( 2 MONTANA EXTENSION SERVICE of oats, barley and rye may be largely prevented by adopting the methods of seed treatment described in this bulletin. What Is Smut Smut is produced by a small parasitic plant, mould-like in appearance, belonging to a group called fungi (Fig. 2). Smut lives most of its life within and at the expense of the wheat plant. The smut powder, so familiar to all, is composed of myriads of spores which correspond to seeds in the higher plants. In the process of harvesting and threshing, these spores are dis· I Fig'.
    [Show full text]
  • The History, Fungal Biodiversity, Conservation, and Future Volume 1 · No
    IMA FungUs · vOlume 1 · no 2: 123–142 The history, fungal biodiversity, conservation, and future ARTICLE perspectives for mycology in Egypt Ahmed M. Abdel-Azeem Botany Department, Faculty of Science, University of Suez Canal, Ismailia 41522, Egypt; e-mail: [email protected] Abstract: Records of Egyptian fungi, including lichenized fungi, are scattered through a wide array Key words: of journals, books, and dissertations, but preliminary annotated checklists and compilations are not checklist all readily available. This review documents the known available sources and compiles data for more distribution than 197 years of Egyptian mycology. Species richness is analysed numerically with respect to the fungal diversity systematic position and ecology. Values of relative species richness of different systematic and lichens ecological groups in Egypt compared to values of the same groups worldwide, show that our knowledge mycobiota of Egyptian fungi is fragmentary, especially for certain systematic and ecological groups such as species numbers Agaricales, Glomeromycota, and lichenized, nematode-trapping, entomopathogenic, marine, aquatic and coprophilous fungi, and also yeasts. Certain groups have never been studied in Egypt, such as Trichomycetes and black yeasts. By screening available sources of information, it was possible to delineate 2281 taxa belonging to 755 genera of fungi, including 57 myxomycete species as known from Egypt. Only 105 taxa new to science have been described from Egypt, one belonging to Chytridiomycota, 47 to Ascomycota, 55 to anamorphic fungi and one to Basidiomycota. Article info: Submitted: 10 August 2010; Accepted: 30 October 2010; Published: 10 November 2010. INTRODUCTION which is currently accepted as a working figure although recognized as conservative (Hawksworth 2001).
    [Show full text]
  • Corn Smuts S
    A Pacific Northwest Extension Publication Oregon State University • University of Idaho • Washington State University PNW 647 • July 2013 Corn Smuts S. K. Mohan, P. B. Hamm, G. H. Clough, and L. J. du Toit orn smuts are widely distributed throughout the world. The incidence of corn smuts in the Pacific Northwest (PNW) varies Cby location and is usually low. Nonetheless, these diseases occasionally cause significant economic losses when susceptible cultivars are grown under conditions favorable for disease development. Smut diseases of corn are, in general, more destructive to sweet corn than to field corn. The term smut is derived from the powdery, dark brown to black, soot-like mass of spores produced in galls. These galls can form on various plant parts. Three types of smut infect corn—common smut, caused by Ustilago maydis (= Ustilago zeae); head smut, caused by Sphacelotheca reiliana; and false smut, caused by Ustilaginoidea virens. False smut is not a concern in the PNW, so this publication deals University S. Krishna by State Mohan,Photo © Oregon only with common and head smuts. Figure 1. Common smut galls on an ear of sweet corn. Each gall represents a single kernel infected by the common Common smut smut fungus. Common smut is caused by the fungal pathogen U. maydis and is also known as boil smut or blister smut (Figure 1). Common smut occurs throughout PNW corn production areas, although it is less common in western Oregon and western Washington than east of the Cascade Mountains. Infection in commercial plantings may result in considerable damage and yield loss in some older sweet corn cultivars, but yield loss in some of the newer, less susceptible cultivars is rarely significant.
    [Show full text]
  • Common Diseases of Small Grains and Their Management
    Common Diseases of Small Grains and Their Management Gary C. Bergstrom Cornell University Section of Plant Pathology and Plant-Microbe Biology Central New York Small Grains Workshop February 3, 2015 West Winfield, NY Plant Disease: A condition of a plant of abnormal growth or function Plant Pathogen: A living organism that can incite plant disease Gary C. Bergstrom, Cornell University When a microbe feeds on a: It is called a: Living host parasite Non-living host saprophyte When a pathogen: It is called a: Gets its nutrients from biotroph living cells Kills host cells before necrotroph acquiring nutrients Gary C. Bergstrom, Cornell University Causal agents (pathogens) of infectious plant diseases • FUNGUS • OOMYCETE • BACTERIUM • VIRUS • NEMATODE Gary C. Bergstrom, Cornell University Factors affecting disease epidemiology and management • Pathogen dissemination potential – (long-distance, regional, local) • Survival in debris • Vector relationship • Favorable environment Gary C. Bergstrom, Cornell University Methods of disease management • Cultural (e.g., crop rotation) • Resistance (e.g., resistant or tolerant varieties) • Biological (e.g., biopesticides) • Chemical (e.g., fungicide seed treatment) • Regulatory (e.g., seed certification) Gary C. Bergstrom, Cornell University Yellow dwarf of cereals and grasses Gary C. Bergstrom, Cornell University Yellow dwarf of cereals and grasses • Pathogen: Barley yellow dwarf luteovirus and Cereal yellow dwarf polerovirus strains • Host range: all grasses • Symptoms: leaves yellow to red or purple; stunting • Conditions: early planting; large aphid populations • Survival: in infected aphids and grasses • Spread: by aphids (short & long distance) • Management:plant after Hessian fly free date, systemic seed insecticides Gary C. Bergstrom, Cornell University Soilborne viruses © G.C. Bergstrom Gary C.
    [Show full text]
  • Study of Fungi- SBT 302 Mycology
    MYCOLOGY DEPARTMENT OF PLANT SCIENCES DR. STANLEY KIMARU 2019 NOMENCLATURE-BINOMIAL SYSTEM OF NOMENCLATURE, RULES OF NOMENCLATURE, CLASSIFICATION OF FUNGI. KEY TO DIVISIONS AND SUB-DIVISIONS Taxonomy and Nomenclature Nomenclature is the naming of organisms. Both classification and nomenclature are governed by International code of Botanical Nomenclature, in order to devise stable methods of naming various taxa, As per binomial nomenclature, genus and species represent the name of an organism. Binomials when written should be underlined or italicized when printed. First letter of the genus should be capital and is commonly a noun, while species is often an adjective. An example for binomial can be cited as: Kingdom = Fungi Division = Eumycota Subdivision = Basidiomycotina Class = Teliomycetes Order = Uredinales Family = Pucciniaceae Genus = Puccinia Species = graminis Classification of Fungi An outline of classification (G.C. Ainsworth, F.K. Sparrow and A.S. Sussman, The Fungi Vol. IV-B, 1973) Key to divisions of Mycota Plasmodium or pseudoplasmodium present. MYXOMYCOTA Plasmodium or pseudoplasmodium absent, Assimilative phase filamentous. EUMYCOTA MYXOMYCOTA Class: Plasmodiophoromycetes 1. Plasmodiophorales Plasmodiophoraceae Plasmodiophora, Spongospora, Polymyxa Key to sub divisions of Eumycota Motile cells (zoospores) present, … MASTIGOMYCOTINA Sexual spores typically oospores Motile cells absent Perfect (sexual) state present as Zygospores… ZYGOMYCOTINA Ascospores… ASCOMYCOTINA Basidiospores… BASIDIOMYCOTINA Perfect (sexual) state
    [Show full text]
  • Master Thesis
    Swedish University of Agricultural Sciences Faculty of Natural Resources and Agricultural Sciences Department of Forest Mycology and Plant Pathology Uppsala 2011 Taxonomic and phylogenetic study of rust fungi forming aecia on Berberis spp. in Sweden Iuliia Kyiashchenko Master‟ thesis, 30 hec Ecology Master‟s programme SLU, Swedish University of Agricultural Sciences Faculty of Natural Resources and Agricultural Sciences Department of Forest Mycology and Plant Pathology Iuliia Kyiashchenko Taxonomic and phylogenetic study of rust fungi forming aecia on Berberis spp. in Sweden Uppsala 2011 Supervisors: Prof. Jonathan Yuen, Dept. of Forest Mycology and Plant Pathology Anna Berlin, Dept. of Forest Mycology and Plant Pathology Examiner: Anders Dahlberg, Dept. of Forest Mycology and Plant Pathology Credits: 30 hp Level: E Subject: Biology Course title: Independent project in Biology Course code: EX0565 Online publication: http://stud.epsilon.slu.se Key words: rust fungi, aecia, aeciospores, morphology, barberry, DNA sequence analysis, phylogenetic analysis Front-page picture: Barberry bush infected by Puccinia spp., outside Trosa, Sweden. Photo: Anna Berlin 2 3 Content 1 Introduction…………………………………………………………………………. 6 1.1 Life cycle…………………………………………………………………………….. 7 1.2 Hyphae and haustoria………………………………………………………………... 9 1.3 Rust taxonomy……………………………………………………………………….. 10 1.3.1 Formae specialis………………………………………………………………. 10 1.4 Economic importance………………………………………………………………... 10 2 Materials and methods……………………………………………………………... 13 2.1 Rust and barberry
    [Show full text]
  • Control of Loose Smut of Barley Richard Mullington Lewis Iowa State University
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1962 Control of loose smut of barley Richard Mullington Lewis Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Agriculture Commons, and the Plant Pathology Commons Recommended Citation Lewis, Richard Mullington, "Control of loose smut of barley " (1962). Retrospective Theses and Dissertations. 2102. https://lib.dr.iastate.edu/rtd/2102 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. This dissertation has been 63-1587 microfilmed exactly as received LEWIS, Richard Mullington, 1920- CONTROL OF LOOSE SMUT OF BARLEY. Iowa State University of Science and Technology Ph.D., 1962 Agriculture, plant pathology University Microfilms, Inc., Ann Arbor, Michigan CONTROL OF LOOSE SMUT OF BARLEY by Richard Mullington Lewis A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Subject: Plant Pathology Approved: Signature was redacted for privacy. In Charge of Major Signature was redacted for privacy. Head of Major D rtment Signature was redacted for privacy. D^ân of Grad lollege Iowa State University Of Science and Technology Ames, Iowa 1962 ii TABLE OF CONTENTS Page INTRODUCTION 1 PERTINENT LITERATURE 3 MATERIALS AND METHODS 6 Materials 6 Methods of Application 7 Seed Treatment Evaluations 12 EXPERIMENTAL RESULTS 15 1952 Results 15 1953 Results 18 195m- Results 24 1955 Results 39 DISCUSSION 41 SUMMARY AND CONCLUSIONS 48 LITERATURE CITED 51 ACKNOWLEDGEMENTS 53 APPENDIX 54 iii LIST OF TABLES Page Table 1.
    [Show full text]
  • Pathogenicity Resulting from Mutation at the B Locus of Ustilago Maydis
    Proceedings of the National Academy of Sciences Vol. 68, No. 3, pp. 533-535, March 1971 Pathogenicity Resulting from Mutation at the b Locus of Ustilago maydis P. R. DAY, S. L. ANAGNOSTAKIS, AND J. E. PUHALLA The Connecticut Agricultural Experiment Station, New Haven, Conn. 06504 Communicated by J. G. Horsfall, December 14, 1970 ABSTRACT This paper explores the genetic basis of the both factors (a# b$) form mycelial colonies (3). Artificial ability of the fungus, Ustilago maydis, to induce neo- mixtures showed that the method was sufficiently sensitive to plastic galls in the corn plant (Zea mays). Pathogenic mutants of U. maydis were produced by ultraviolet ir- detect one mutant diploid as a mycelial spot in a background radiation of cultures of nonpathogenic diploids homozy- of 5 X 105 cells per plate. Three b factors were used: bG, bD, gous at the b locus. The mutants formed smaller neo- and bl. plasms, produced fewer teliospores, and showed higher frequencies of meiotic failure and lower rates of basidio- RESULTS spore survival than did the wild-type fungus. In each selection experiment, mycelial colonies were picked The corn plant (Zea mays) suffers from a neoplastic disease from CM X2 and inoculated to corn seedlings to test for induced by a fungus, Ustikzgo maydis. Two genetic loci (a and pathogenicity. The results are shown in Table 1. The two b) in the fungus control sexual compatibility and pathogenic- diploids homozygous for bG were obtained independently as ity. The a locus has two alleles and controls cell fusion in the unreduced products from a natural infection and carried no pathogen (1).
    [Show full text]
  • Topic – Loose Smut of Wheat
    Course – M. Sc. Botany Part 1 Paper III Topic – Loose Smut of Wheat Prepared by – Dr. Santwana Rani Coordinated by – Prof. (Dr.) Shyam Nandan Prasad Loose Smut of Wheat ➢ The disease loose smut of wheat is caused by ustilago nuda tritici. ➢ Incidence is more in north than in south India. ➢ Country wide loss is about 2-3%of total yield. ➢ There was a loose smut epidemic in Punjab, Haryana and western U.P. in 1970-75. Distribution: ➢ All wheat growing regions of India. ➢ Particularly in Punjab, Haryana, U.P. and certain regions of M.P. Symptoms: ➢ Symptoms appear after ear emergence. ➢ Diseased ear emerged first than normal in some varieties ➢ Mostly all ears is converted into a black mass of spores ➢ All the floral parts of the head, except the rachis and pericarp membrane, are invaded by mycelium of the fungus and converted into loose aggregation of smut spores(teliospores). ➢ Significant reduction in tillering. ➢ Except awns all parts of ear converted into smut spore. ➢ Black powder in ear-covered by slivery membrane. ➢ Membrane burst later & smut spore release. ➢ Group of smut spore called sorus. ➢ High respiration and low dry weight. Causal agent: Etiology Pathogen - Ustilago nuda tritici. (Syn. U. segetum var. tritici) Systematic position: Kingdom: Fungi Phylum: Basidiomycota Sub phylum: Ustilaginomycotina Class: Ustilaginomycetes Order: Ustilaginales Family: Ustilaginaceae Genus: Ustilago Species: U tritici (Pers.) Pathogen characters: ➢ It is an internally seed borne fungal disease. ➢ It causes systemic infection. ➢ The teliospores of the fungus are pale, olive brown, spherical to oval in shape, about 5-9 micro diameter and are adorned with minute echinulations on the wall.
    [Show full text]