PRINCIPLES PLANT PATH
PRINCIPLES PLANT PATH PLP 3343
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PLP 3343 Introductory Plant Pathology Outline of Lecture 16 Basidiomycete Rots and Parasitic Plants Fall 2008 1 Basidiomycete Rots 2 Parasitic Plants Basidiomycete Rots Systematics Morphological Characteristics 0 Septa o o 0 Meiospores Taxonomy of Basidiomycete rotting fungi Class Agaricomycetes Order Cantharellales 0 Anamorphic Rhizoctom39a Order Atheliales 0 Anamorph 0 Teleomorph Order Agaricales 0 Armillaria Order Polyporales 0 Numerous Rhizoctonia Diseases Mycelia sterilia morphology Teleomorphs 0 Multinucleate 0 Binucleate Anastomosis groups 0 Defn Rhizoctonia Diseases Disease Cycle Primary inoculum Penetration structure Photos Crops Turf Disease Management 0 Cultural o o o o o 0 Chemical 0 o O Sclerotium Diseases Diseases Host range 0 Pathogenesis Conducive environment 0 0 Survival Dissemination Morphological features 0 0 Disease Management 0 Cultural o o o o o 0 Chemical 0 O Sclerotium Sclerotinia Phylum Hyphae Disease Conducive environment Resting Structure Virulence Factors Hosts Armillaria Root Rot 0 Gilled Mushroom 0 Hosts 0 o 0 Symptoms Disease Cycle Dissemination Photos Disease Foci Fox re Disease Management 0 Cultural o o o o 0 Chemical 0 o O Wood Rots Polypores Two forms of decay l O Impacts Disease cycle 0 Inoculum 0 Penetration site Photos Parasitic Plants Kingdom Reproduction Diveristy Parasitism o o Systematics in Eukaryota Economically important Parasitic Plants 0 Dodder 0 Mistletoes 0 Dwarf Mistletoes 0 Witchweed Dodder o o o 0 Management Disease Cycle 0 Resting structure 0 Infection structure True 01 Leafy Mistletoe Parasitism Dissemination Management State Flower Dwarf Mistletoe Economically affect commodity Parasitism Symptom Management 0 o o o 0 Disease cycle 0 Dioecious 0 Seed dispersal 0 Penetration 0 Photos Witchweed Geographic location 0 0 Seed Parasitism Management 0 o 0 Disease Cycle Primary inoculum seed germination inducers Penetration PLP 33435343 Principles of Plant Pathology Outline of Lecture 4 Disease Cycles Fall 2008 1 i Disease Cycle or 7 Infection Cycle l Primary Inoculum Symptom development Dissemination Pathogen GrowthReproduction Inoculation Dissemination of secondary inoculum Attachment Survival resting structure Penetration Dormancy Infection Primary Inoculum Invasion Dissemination Colonization Latent 0r Incubation Period Monocyclic Diseases Attachment Polycyclic Diseases MucilageAppressoriurn Modes of Penetration 1 Active appresoriumpenetration peg infection cushions hyphopodiurn germ tube 2 Passive Colonization Intracellular vs lntercellular a haustorium b bacteria c nematodes d Viruses Long distance movement a b Pathogen Reproduction a meiosis V mitosis b haploid c dikaIyotic d heterokaiyotic e diploid Dissemination a b c d e Survival 7 on host or in absence of host PLP 33435343 Principles of Plant Pathology Outline of Lecture 24 Viruses and Viroids part 2 Fall 2008 1 Virus Disease and Vector Management Speci c Diseases 2 Tobacco Mosaic Virus 3 Barley Yellow Dwarf 4 Tomato Spotted Wilt 5 Viroids Virus Disease and Vector Management 1 Chemicals 2 Exclusion a 3 Eradication a b 4 V Genetic Resistance a b i ii Cultural control or avoidance of a VI V Host Genetic Resistance 0 Rgenes recognize 0 Results in 0 Source of Rgenes o Germplasm sources Tomato R genes Wheat Soilbome Mosaic 0 Epidemics 0 Resistance 0 0 Virus Genus 0 Vector 0 Other Virus Transgenic Resistance 0 Transgenes 0 Examples 0 o o o o Papaya Ringspot Virus 0 Epidemics o Transgene 0 Resistance level Vector Transmission in uence 0 0 Transmission Types 1 a 2 a b a b 4 a b 0 Vector Management In relation to vector transmission 0 Nonpersistent o O o 0 Semipersistent and Persistent o Aphid Management 0 Preventative o o o o 0 Direct Example Viruses vectors 0 Speci c Virus Diseases Tobacco mosaic tobamovirus TMV O 0 Transmission 0 o 0 Hosts 0 Management 0 1 o o o o 0 Other management strategies 0 0 Three genes i ii iii Replication CelltoCell Movement of TMV Barley yellow dwarf luteovirus BYDV 0 Structure 0 Transmission 0 I Aquistion I Latent I Transmission 0 Hosttissue infected o 0 Symptoms conducive environment 0 o 0 Host range 0 Vectors winged aphids 0 Replication 0 Symptoms BYDV Management 0 o 0 Planting date 0 Aphids o o 0 Tomato spotted wilt tospovirus T SWV Stucture 0 Genome o o 0 from host 0 Vector 0 Transmission 0 Acquisition 0 Host range 0 Insect midgut Salivary gland TSWV Virions o 0 Symptoms on peanut 0 Timing 0 Yield losses Symptoms on Tomato and Tobacco o TSWV Management 0 Vector acquisition only by 0 Insecticides o O Viroids o 0 Transmission 0 o 0 Management 0 Echusion o 0 Examples 0 O PLP 33435343 Principles of Plant Pathology Outline of Lecture 23 Viruses Fall 2008 1 History 2 Size amp Shape Systematics 3 Structure 4 Vectors 5 Management History Mayer amp Ivanowski o Beij erinck o o 0 Stanley 0 Size Scale 7 Microscopy 7 Shapes cow E Electron microscopy Inclusion bodies What are they Chemical Stucture 0f Viruses Virion Components 1 Nucleic Acid genome a b c d 2 3 Molecular Biology Review Central dogma of molecular biology 7 Eukaryotic Gene Expression Viral Genome Replication ssRNA Viruses Coat Protein Replicases Retroviruses have extra enzyme Viral Genome Structure Model TMV Virus Encoded Proteins 1 2 3 TMV Genome Replication Process 1 8095 Virus Taxonomy 0 Nucleic acid content 0 Original taxonomy prel990s 0 Common name system Current Taxonomy based on o 0 Virus Nomenclature 0 Old 0 New Virus Movement in planta 0 Celltocell 0 Long Distance 0 Proteins involved Virus Transmission 1 Vectors Virus Vector Biology Pictures of Vectors Nonvector Virus Transmission Types of Vector Transmission Model Aphid 1 Nonpersistent a b 2 Semipersistent a b 3 Persistent a b 4 Persitent a b Transmission Type Determines 1 2 Virus Virus Interactions Cross Protection PLP 33435343 Principles of Plant Pathology Outline of Lecture 17 Oomycetes Part 1 Fall 2008 1 Oomycetes OOMYCETES 1 General characteristics 2 Downy Mildews 3 White Rusts 4 Pythz39um Diseases 5 Phytophthora Diseases Common name Similarities with true Fungi Kingdom Phylum Class Genera o o Oomycetes vs True Fungi state mycelia tinsel ciliated Cell Walls Oomycetes 0 True Fungi Hyphae I Oomycetes True Fungi Sexual Meiospores 0 Nuclear state I Heterogametangia o o I MatingTypes o Selffertile o Selfinfertile Resting Spores o O Asexual mitospores o o o Zoospores o o Sporangia germination amp Zoospore encystment o o o o o I ChemotaXis 7 Oomycetes Diseases 1 Foliaraerial Diseases 2 Soilborne Diseases Downy Mildews I I Disease Cycle 0 Resting Structure Parasitic structure Disease Management 0 Cultural o o o 0 Chemical 0 0 White Rusts Genus o o 0 Symptoms o o 0 Local crops affected Disease Management o o o Diseases Caused by Pythium and Aphanomyces Damping Off 7 o o Root Rots o o o o Fruit Rots o o o a Disease Management 0 Resistance 0 Damping off 7 0 Chemicals 0 Cultural o o O PLP 33435343 Introductory Plant Pathology Outline of Lecture 10 Introduction to the Fungi Fall 2008 1 Fungi now split into 3 kingdoms 1 Eukaryotes organelles i 2 Nutrition 3 Cell Wall 4 Reproduction Spores 2 Cells iii 1 2 3 Plasmodia and amoebae 4 5 3 Yeast 1 Dimorphism 4 Filamentous fungal cells 7 terms 1 Hyphae 2 3 4 5 Myceliaum 5 Plasmodia amoebae zoospores 6 Fungal Reproduction 1 2 3 4 Asexual i ii iii Sexual i ii iii iV 7 Varied nuclear states during reproduction 8 Generalized life cycles 1 2 Basidiomycetes dikaryotic hyphae LIIgt03 Oomycetes Ascomycetes Sterile fungi mostly basidiomycetes and ascomycetes Imperfect fungi mostly ascomycetes 9 Mitospores 7 asexual 1 2 3 Conidia borne on borne inon Sporangiospores in Zoospores in 10 Conidia and other mitospores identification 1 2 3 cell number pigment i shapes 11 Conidiomata 1 conidiophores 5 pycnidia 12 Meiospores 7 sexual 1 Oospores 2 3 4 13 Fungal taxonomic names 1 Anamorph 2 Teleomorph 3 Holomorph 4 Why so many names 14 Current taxonomic classification FLOs 1 Kingdom Protozoa i ii 2 Kindom Stramenopila i True Fungi 3 Kingdom Fungi i ii iii iV V Deuteromycetes 4 Ribosomal genes rDNA 5 rDNA Tree of Life 6 Multigene tree of Eukaryota 7 Cell Walls Polysaccharides j Myxomycetes Plasmodiophorids iii Oomycetes 1V Chytridiomycetes V Zygomycetes Vi Ascomycetes Vii Basidiomycetes 15 Spore Names STRUCTURES Meiospores Mitospores Somatic form TMyxomyce tesr spores Swatmeans Myxvamo bae Pla S39in39Odium Pl39a m bdj0p li 6 d Re s t i n g spores Pla mbdi m Plant Diseases caused by 16 Protozoan FLOs 1 Myxomycetes i signs 2 Plamodiophorids i symptoms 17 Primitive true fungi 1 Chytridiomycetes i Symptoms 18 Myxomycetes slime molds 1 pathogens 2 nutrition 3 morphology 4 Mgt 19 Plasmodiophorids 1 protists 2 3 4 Viruses i ii 5 Mgt 6 Clubroot of crucifers i Caused by Plasmodiophom brassicae ii Penetration iii Mgt 1 2 3 7 Virus Vectors i Plasmodiophorids 1 causal genus 2 Viruses 3 host 4 Mgt ii Chytridiomycetes 1 causal genus 2 Viruses 3 Mgt PLP 33435343 Principles of Plant Pathology Outline of Lecture 8 Prokaryotic Plant Pathogens Fall 2008 1 Major Characteristics and Important Genera a DNA b Cells i ii iii iv V 2 Classification a Two Class System b Phylogenetically c 1 Eubacteria Genera i Gram Negative easily culturable 1 2 3 4 ii Gram Negative fastidious 2 slow growing on special media 1 iii Gram Positive culturable 1 d 2 Mollicutes Gram Negative unculturable or extremely fastidious i Fastidiously culturable 1 ii Unculturable 1 e Tree of Life 7 Bacterial phylogenetics i Gram vs 7 ii Proteobacteria Gram 7 1 Alpha 2 Beta 3 Gamma a b c d iii Actinobacteria Gram 1 a 2 a iV Firmicutes Gram includes Bacilli and Clostridia 1 Mollicutes Gram 7 a b 3 Bacterial Motility a Arrangement i ii iii b Bacterial streaming 4 Nutrition habtitat vectors Eubacteria Mollicutes Culturability Saprobic survival Plant tissues inhabited Insect vectors 5 Pathovars a Xanthomonas campestris pv i ii iii b Pseudomonas syringae pv i ii iii 6 Survival a In soil i ii b Common survival habitats i ii iii 7 Dissemination a b c d 8 Infection a General requirements i ii iii 1 Natural penetration sites a b c d 9 General Bacterial Disease Management a Ease of control b Management practices general order to proceed i Genetic Resistance 1 ii 1 2 Sanitation a b c iii Eradication from media and water c Chemical pesticides i ii iii i ii 10 Fastidious Bacterial Diseases a Typical Symptoms b Fastidious XLB s i Pathogen 1 strains 2 ii iii iV 1 V 1 Vi Most important diseases 1 2 Vii Viii Pierce s Disease ix Citrus variegated chlorosis CVC X BLS Symptoms versus abiotic leaf scorch 1 2 Xi Management of Xylella Diseases 1 2 3 4 Nematology Lecture 2 Outline Plant Pathology 3343 Fall 2008 Biology of Four Important Plant Pathogenic Nematodes Root knot nematode Meloidogyne Life cycle eggshatching gelatinous matrix infectionfeeding feeding site giantcells mitosis without cytokinesis galling nematode shape reproduction parthenogenesis mitotic 0r meiotic lifecycle overwintering host plant effects Cyst Nematodes Heterodera and Globodera species Life cycle eggshatching infectionfeeding feeding site syncytium galling nematode shape reproduction lifecycle overwintering host plant effects races Lesion nematode Pratylenchus spp Life cycle e ggs hatching infectionfeeding nematode shape reproduction lifecycle overwintering host plant effects Pinewood nematode Bursaphelenchus xylophilus Life cycle eggshatching vectored by cerambycid beetles Monochamus pine wood or sawyer beetles infectionfeeding commonly infested pine are Jack Scotch Shortleaf White Loblolly and Slash reproduction lifecycle two life cycles of B xylophz39lus feeding stage bluestain fungus C eratocystis spp dispersal stage dauerlarvae beetle spiracles overwintering host plant effects PLP 33435343 Principles of Plant Pathology Outline of Lecture 7 Abiotic disorders Fall 2008 1 General characteristics 2 Diagnosing abiotic disorders 1 2 e f 3 Categories a Injuries b Abiotic disorders c Secondary pathogens b Weather related Veitebrate related injuries Environmental excess or deficiency Nutritional imbalances 7 deficiencies and toxicities excesses pH 0 macronutrients 0 micronutrients 8 Pesticide phytotoxicity 9 de icing salt 10 Cultural practices 11 Air Pollution Symptoms Air quality Primary pollutants Secondary pollutants Ozone mimic PLP 33435343 Principles of Plant Pathology Outline of Lecture 14 Bunts and Smuts Fall 2008 1 Basidiomycetes 7 general characterisitcs 2 Smuts and Bunts Basidiomycetes Phylum 7 Basidiomycota Subphyla 7 1 Pucciniomycotina Urediniales 7 Rusts a Septa 2 Ustilaginaomycotina Ustilaginales 7 Bunts amp Smuts a Septa 3 Agaricomycotina agarics 7 eshy basidiomata mushrooms jelly fungi polypores etc a Septa Meiospores Nuclear state Borne on Ballistospores Nuclear state during most of life Mating types Clamp connections Smuts and Rusts Resting spore Germinates to form what Smut Diseases Economic hosts 0 Genera 0 Economic Impacts O 0 General Disease Cycle 0 Reproduction o o o 0 Tissue infected 0 General Management Speci c Smut Diseases 0 Corn smut 7 0 Loose smut of7 0 Wheat o Barley o Oats 0 Common Bunt 7 0 Kamal Bunt 7 Corn Smut 0 Primary inoculum o o 0 Infection 0 o 0 Symptoms and signs 0 0 Disease Management 0 o 0 Disease Cycle Dimorphism Mexican delicacy Loose Smut of Wheat and Barley 0 Primary inoculum o 0 Primary infections 0 o 0 Symptoms and Signs 0 o o 0 Disease management 0 o O Disease Cycle Primary inoculum Primary infection Basidiospores Common Bunt of Wheat Tilletz39a spp 0 Other names 7 0 Primary inoculum o o 0 Primary infection 0 0 Symptoms and signs 0 o 0 Disease Management 0 o 0 Disease Cycle Primary inoculum Disease Management of Loose smut and common bunt Kamal Bunt 0 History 0 First report 0 Locations in US 0 Economic impacts I Odor I Quarantine I Certi cation Primary infections 0 O 0 Seed treatment effective Fungicides How does Karnal bunt differe from smuts and common bunt O O Teliospores Primary inoculum Epiphytic Secondary inoculum Penetration site Flower infections Study questions pW QMrbE N o What kind of cell conections are present in smuta bunts and rusts How are basidiospores formed How are basidiospores discharged Are smutsbunts basidiospores forcibly discharged What does ballistospores mean How does the basidiomycete mycelium become nn How is the nn state of basidiomycete cell preserved What is the role of the clamp connections What kind of spore is used by Smuts and Rusts as resting spores Compare Smuts vs Rusts What is the function of the teliospores 12 For each ofthe diseases below describe E Causal agent dissemination Host Fquot c Disease cycle d symptoms e signs f Control Corn Smut Loose smut Common Bunt Kama Bunt PLP 33435353 Introductory Plant Pathology Outline of Lecture 9 Prokaryotic Plant Pathogens Fall 2008 Mollicute diseases 1 Mollicute Characteristics a cell b Host cells c Vectors d Genera i ii e Originally 2 Typical life cycle Inoculation E Fquot Vector host c Latent period d Transmission e Plant host f Colonization g Survival overwintering 3 Spiroplasma Diseases a Cell morphology b Cultural morphology c Disease examples i ii 4 Phytoplasma Diseases a Aster yellows i Symptoms o O 0 ii Disease Management 0 O O 5 Bacterial Diseases a Bacterial spots and blights b Genera i ii c Disease Management i ii iii iV d Disease cycle wild re oftobacco Inoculation Penetration ii 39 Colonization iV Symptom expression 0 O lt Overwintering O 0 e Wild re of tobacco and soybean i Disease management 0 ii Cultural characteristic syringae pvs campesm39s pvs Season mgt f resistance gene test 6 Twig amp Stem Dieback amp Canker a Fire Blight Causal bacterium ii Pome hosts ii 39 Survival iV Disease management 0 O 0 Disease cycle lt 0 Inoculaiton 0 Penetration 0 Infection Colonization Symptoms Overwintering 7 Vascular Wilts a Xylem inhabitants b C d e Bacterial wilt of cucurbits i Causal bacterium ii Vector iii Mgt Bacterial canker amp wilt of tomato i Causal bacterium ii Mgt Ring Rot of Potato i Causal bacterium ii Mgt Southern or bacterial wilt i Causal bacterium formerly Pseudomonas now ii Mgt 8 Galls 7 Crown Gall a b C Causal bacterium Pathogenesis M gt i ii iii iV V d Agrobacterium as atool 9 Soft Rots a Causal bacterium b Hosts survival c Pathogenesis i ii d M gt i e Disease cycle i Inoculation of hosts ii Infection iii Symptoms o 0 Black leg of potato seedlings iV Vectors V Survival f Scab of Potato i Causal bacterium 0 Classi cation ii Conducive enVironment iii Sencondary infections iV Mgt o PLP 33435343 Principles of Plant Pathology Outline of Lecture 18 Oomycetes Part 2 Fall 2008 1 Oomycetes a Pythz39um and Aphanomyces Diseases b Phytophthora Diseases OOMYCETES Diseases Caused by Pythium and Aphanomyces Damping Off 7 o o o 0 Root Rots o o o 0 Fruit Rots o o o 0 Disease Management 0 Resistance 0 Damping off 7 0 Chemicals 0 Cultural Pythium Blight 0f Turf 0 aka 0 Types of grasses susceptible 0 Conducive weather 0 Patch symptoms 0 Movement of inoculum Symptoms o 0 Signs 0 Diagnostic signs 0 0 Disease cycle primary inoculum Disease management 0 o Diseases caused by Phytophthora spp Late Blight of Potato and Tomato History 0 o o 0 Father of Plant Pathology Causal oomycete Hosts 0 o o 0 Symptoms 0 Foliar Signs Symptoms 0 Late foliar 0 Tomato fruit 0 Potato tubers Primary inoculum o o o 0 Disease Cycle Mating types 0 o Fungicide Resistance 0 0 New strains Disease Management 0 O Phytophthora Root Rots Hosts Symptoms above ground 0 o o o o 0 Symptoms below ground 0 o o 0 Management 0 0 Tree planting 0 Nursery greenhouses o o Shrubs amp trees 0 O O O O Recycled Water at Nurseries o o Inlet for water 0 0 Water treatment methods 0 O Sudden Oak Death New name Causal oomycete Mating types and locations 0 0 Symptoms of sudden oak death 0 Hosts o 0 Symptoms of Ramorum blight 0 Hosts 0 o 0 Characteristics Spores 0 Resting spore o Potentially affected regions of the Us 0 o Containment Measures 0 o o 0 Host range 0 o 0 Disease Management PLP 33435343 Principles of Plant Pathology Outline of Lecture 22 Disease Forecasting Fall 2008 Disease Advisory Disease Forecast Examples of Disease Advisory Outputs 1 2 3 Purpose ofa Disease Warning System 1 Disease Warning Systems Control Costs 1 Direct 2 Indirect Requirements for implementing a Disease Warning System 1 959 Constraints to Adoption of Forecasting Systems 1 Approaches to Developing a Disease Warning System Fundamental Empirical Warning systems can be based on 1 Amount or efficacy of initial inoculum is used for l Example Stewarts Wilt of Corn Major parameter used to indirectly assess initial inoculum Example Downy Mildew Warning System Major Inputs used to make warning 1 Disease increase in secondary cycles Assume If assumptions don t hold then what What is the usual action Fundamental Advisory Example with a Secondary Cycle Pecan Scab Advisory Overwintering inoculum Climate data recorded 1 2 Statistical Analysis used Scab Hour hour with T gt 21C 70F d RH gt 90 Surpassing scab hours threshold results in disease in Decision Rule Setting Thresholds dependent on host susceptibility The Thresholds 1 Highly susceptible cultivars 2 Moderately Susceptible cultivars 3 Natives low susceptibility The Model Outputs AgWeathermesonetorg l 2 3 4 Empirical Advisory Example Sclerotinia blight of Peanut SkyBit is Parameters Tested in Statistical analyses Three main weather inputs required in the advisory l 2 3 Residual Plots help to Fungicide equivalence is PLP 33435343 Principles of Plant Pathology Outline of Lecture 21 Plant Disease Epidemiology Fall 2008 De nitions Disease cycles Disease assessment units of measure Modeling disease progress Management Decisions Definitions Epidemic vs Epiphytotic Epidemiology Pandemic Disease Cycles Disease epidemics pyramid components 1 959 Infection Cycle Inocula 1 2 Factors affecting epidemic development 0 Plant host 0 Humans 0 Pathogen 0 EnViroment Disease Assessment various measures 1 Incidence 2 Severity 3 4 Why assess diseases 0 Disease Progress Models Within one growing season 0 o 0 Over multiple growing seasons 0 Determining which model a disease falls under 0 Monocyclic Diseases 0 Infection cyclesseason 0 Inoculum Examples 0 Disease Progress Curve Disease S everity Time Polycyclic Diseases 0 Infection cyclesseason 0 Inoculum 0 Important inoculum Examples 0 Disease Progress Curve Disease S everity Time Interest Combination Diseases Monocyclic and Polycyclic Phases 0 Pathogen type 0 Primary inoculum Two spore stages 0 0 Disease progress curve Examples 0 O 0 How to determine if it s a combination disease control primary inoculum and control the disease Polyetic Diseases 7 Modeled over multiple growing seasons 0 Primary inoculum 0 Epidemic severity 0 Hosts affected 0 0 Examples 0 Monocyclic o Polycyclic Disease Progress Curves Disease Disease Severity Severity Time Time Disease Severity Time Mathematically Modeling Plant Diseases 0 Inoculum production 0 Disease progress 0 Model validation o Monocyclic Inoculum Production 0 Q primary inoculum 0 T time in 0 K Monocyclic Disease Progress 0 Within growing season 0 o Slope is o P r quot 39to Q Polycyclic Inoculum Production 0 equation 0 qT primary inoculum 0 qTAT secondary inoculum 0 AT time change in or o k Polycyclic Disease Progress 0 Slope The upper limit of disease 0 Proportion of disease tissue 0 Correction factor 0 Slopes decrease as diseased tissue proportion approaches 1 Estimating Model Parameters Transformations into linear equations Disease Modeling 7 Empirical Validation Typical parameters 0 Multiple disease assessments are required Reduction of primary inoculum Validation of disease models disease progress curves assess ef ciency of management practices PLP 33435343 Principles of Plant Pathology Outline of Lecture 15 Rusts Fall 2008 1 Rusts Overview 2 General Life cycles 3 Important diseases Order Pucciniales Resting spore What spore form on this resting spore History Rome Pliny Advice 1 festival 2 Modern Plant Pathology 1880s 1900s General Characteristics Nutrition Phylum Hyphae Imp act Spore Stages Spore Nuclear State Spore bearing structure 1 2 Rust Life Cycles Classi cation 1 All 5 spore stages 2 Lacks urediniospores 3 Only teliospores and basidiospores Hosts 1 2 alternate hosts 2 1 host RUST DISEASES Cereal Rusts 1 2 3 Disease Management 0 0 Stem Rust of wheat UredialTelial host Spermatialaecial host Basidiospores infect Aeciospores infect Urediniospores infect Spermatialaecial host Spermagonia form on Aecia form on Management Epidemiology Puccinia pathway Effects of Mgt l 2 Cedar Apple Rust Spermatialaecial host 0 Telialbasidial host 0 o 0 Disease Management 0 o 0 Disease cycle classification Teliospores borne on what structure Color Spermatia vectors Aecia 7 economic impact White Pine Blister Rust SpermatialAecial host 0 o o UredinialTelial host 0 Disease Management 0 o Teliospores borne on what structures Asian Soybean Rust Rust fungus Select agent Introduced into US how Disease Management 0 o o o 0 Seasonal Disease Progression Life cycle 0 o 0 Alternate spermatialaecial host Economic losses if Conducive environment 0 0 Alternative hosts Comparison of Smuts vs Rusts Trait Smuts Host range Disease cycles Host tissues infected Disease Management Resting spores