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Microbiology and Plant Pathology ALAGAPPA UNIVERSITY (Accredited with ‘A+’ Grade by NAAC (with CGPA: 3.64) in the Third Cycle and Graded As category - I University by MHRD-UGC) (A State University Established by the Government of TamilNadu) KARAIKUDI – 630 003 DIRECTORATE OF DISTANCE EDUCATION M. Sc. BOTONY Second Year – Third Semester 34631- MICROBIOLOGY AND PLANT PATHOLOGY Copy Right Reserved For Private Use only Authors: Dr. A. Arun, Associate Professor & Head (i/c), Department of Microbiology, Alagappa University, Karaikudi- 630 003. (Units 1-7) Dr. M. Jothibasu Assistant Professor Department of Botany Alagappa University Karaikudi-03 (Units 8-14) “The Copyright shall be vested with Alagappa University” All rights reserved. No part of this publication which is material protected by this copyright notice may be reproduced or transmitted or utilized or stored in any form or by any means now known or hereinafter invented, electronic, digital or mechanical, including photocopying, scanning, recording or by any information storage or retrieval system, without prior written permission from the Alagappa University, Karaikudi, Tamil Nadu. SYLLABI – BOOK MAPPING TABLE 34631- MICROBIOLOGY AND PLANT PATHOLOGY SYLLABI MAPPING IN BOOK BLOCK-1: SCOPE OF MICROBIOLOGY UNIT I Introduction to Microbiology- Scope of Microbiology- 1-8 Evolution into Science- Characterization of microorganisms. UNIT II Classification of Microorganisms- Archea and Bacteria- 9-15 Characteristics of Bacteria- Morphology -Ultra Structure. UNIT III Nutrition – Growth – Reproduction- Bacterial Cultural and 16-27 Cultural characteristics- Economic importance of bacteria BLOCK 2: VIRUS AND MYCOPLASMAS UNIT IV Virology – General features- Classification of virus- 28-34 Characteristics – Ultra structure. UNIT V Virus- Isolation – Purification –Chemical nature- Replication- 35-46 Transmission- Virions. UNIT VI Prions- Phytoplasma (Including mycoplasma). 47-60 UNIT VII Microbial products- Antibiotics- Enzymes- Human Diseases 61-80 caused by bacteria and viruses. BLOCK 3: PLANT PATHOLOGY UNIT VIII Introduction to Plant Pathology- History – Causal agents 81-94 responsible for Plant diseases. UNIT IX Types of Plant diseases – Methods of studying plant diseases – 95-113 Koch’s postulates – Symptoms of plant diseases. UNIT X Etiology – Plant diseases epidemics – plant diseases forecasting 114-127 – Diseases triangle – Diseases cycle. BLOCK 4: HOST- PATHOGEN INTERACTIONS AND PLANT DISEASES UNIT XI Host – pathogen interactions – Defense mechanisms in plants 128-147 UNIT XII Control Measures –Cultural practices – Chemical control – 148-174 Biology control- Integrated plan diseases management UNIT XIII Plant diseases – Tobacco mosaic virus – Bunchy top of banana 175-202 - Blast and sheath blight of paddy –Citrus canker – Red rot of sugarcane – Downey mildew o grapes. UNIT IV Plant diseases – Late blight of potato – Leaf spot diseases of 203-222 groundnut – Anthracnose of mango – Wilt of cotton – Rust of Wheat. CONTENTS BLOCK 1: SCOPE OF MICROBIOLOGY UNIT I INTRODUCTION TO 1-8 MICROBIOLOGY 1.1 Introduction 1.2 Objectives 1.3 Introduction to Microbiology 1.4 Scope Of Microbiology 1.5 Evolution into Science 1.6 Characterization of Microorganisms 1.7 Check your progress 1.8 Let us Sum up 1.9 Unit – End Exercises 1.10 Answers to check your progress 1.11 Suggested Readings UNIT II CLASSIFICATION OF 9-15 MICROORGANISMS 2.1 Introduction 2.2 Objectives 2.3 Classification of Microorganisms 2.4 Archaea – And Bacteria 2.5 Characteristics of Bacteria 2.6 Ultrastructure of Bacteria 2.7 Check Your Progress 2.8 Let Us Sum Up 2.9 Unit - End Exercise 2.10 Answers to Check Your Progress 2.11 Suggested Readings UNIT III NUTRITION 16-27 3.1 Introduction 3.2 Objectives 3.3 Nutrition – Growth 3.4 Reproduction 3.5 Bacterial Culture and Characteristics of Bacteria 3.6 Economic Importance of Bacteria 3.7 Check Your Progress 3.8 Let Us Sum Up 3.9 Unit - End Exercises 3.10 Answers To Check Your Progress 3.11 Suggested Readings BLOCK 2: VIRUS AND MYCOPLASMAS UNIT – IV VIROLOGY 28-34 4.1 Introduction 4.2 Objectives 4.3 Virology – General Features 4.4 Virus Classification 4.5 Characteristics – Ultrastructure of Virus 4.6 Check Your Progress 4.7 Let Us Sum Up 4.8 Unit - End Exercises 4.9 Answers to Check Your Progress 4.10 Suggested Readings UNIT V VIRUS 35-46 5.1 Introduction 5.2 Objectives 5.3 Isolation of Virus 5.4 Purification 5.5 Chemical Nature of Virus 5.6 Viral Replication 5.7 Transmission of Virus 5.8 Virions 5.9 Check Your Progress 5.10 Let Us Sum Up 5.11 Unit - End Exercises 5.12 Answers To Check Your Progress 5.13 Suggested Readings UNIT VI PRIONS 47-60 6.1 Introduction 6.2 Objectives 6.3 Prions 6.4 Phytoplasma 6.5 Mycoplasma 6.6 Check your progress 6.7 Let us sum up 6.8 Unit – end exercises 6.9 Answers to check your progress 6.10 Suggested Readings UNIT VII MICROBIAL PRODUCTS 61-80 7.1 Introduction 7.2 Objectives 7.3 Microbial Products 7.4 Antibiotics 7.5 Enzymes 7.6 Human Diseases Caused By Bacteria 7.7 Human Diseases Caused By Virus 7.8 Check Your Progress 7.9 Let Us Sum Up 7.10 Unit – End Exercises 7.11 Answers to Check Your Progress 7.12 Suggested Readings BLOCK 3: PLANT PATHOLOGY UNIT- VIII INTRODUCTON TO PLANT PATHOLOGY 81-94 8.1 Introduction 8.2 Objectives 8.3 Introduction to Plant Pathology 8.3.1 Plant diseases 8.4 History of Plant Pathology 8.4.1 Mycology 8.4.2 Plant Bacteriology 8.4.3 Plant Virology 8.4.4 Phytoplasma 8.4.5 Spiroplasma 8.5 Causal Agents Responsible for Plant Diseases 8.5.1 Parasites 8.5.1.1 Biotic agents 8.5.1.2 Prokaryotes 8.5.1.3 Eukaryotes 8.5.2 Non-parasites or Abiotic agents 8.5.3 Fungi 8.5.4 Bacteria 8.5.4.1 Fastidious vascular bacteria 8.5.4.2 Phloem-limited RLB 8.5.4.3 Xylem-limited RLB 8.5.4.4 Non-tissue restricted RLB 8.5.5 Phytoplasma 8.5.6 Spiroplasma 8.5.7 Virus 8.5.8 Viroids 8.5.9 Protozoa 8.5.10 Phanerogamic Parasites 8.6 Answer to Check Your Progress Questions 8.7 Summary 8.8 Key Words 8.9 Self Assessment Question and Exercises 8.10 Further Reading 5-113 UNIT – IX TYPES OF PLANT DISEASES 9.1 Introduction 9.2 Objectives 9.3 Plant Diseases 9.3.1 Introduction to Types of Plant Diseases 9.3.2 Types of Plant Diseases 9.3.2.1Infectious, or biotic, plant diseases 9.3.2.2Noninfectious, or abiotic, plant diseases 9.3.3 Methods of studing plant diseases 9.3.4 Koch’s Postulates 9.3.5 Symptoms of Plant diseases. 9.4 Answer to Check Your Progress Questions 9.5 Summary 9.6 Key Words 9.7Self Assessment Question and Exercises 9.8 Further Reading UNIT – X ETIOLOGY 114-127 10.1 Introduction 10.2 Objectives 10.3 Etiology 10.3.1 Introduction to Etiology 10.3.2 Plant disease epidemics 10.3.2.1 The form of epidemics 10.3.2.2 Annual fluctuations of epidemics 10.3.2.3 Secular fluctuations of epidemics 10.3.2.4 Factors responsible for the establishment of an Epidemic 10.3.2.4.1 (A) Nature of the host 10.3.2.4.2 (B) Nature of the pathogen 10.3.2.4.3 (C) Environment 10.3.2.4.4 Accumulation of susceptible Individuals 10.3.2.4.5 Heightened disease proneness of Host 10.3.2.4.6 Presence of appropriate alternate Hosts 10.3.2.4.7 Presence of an aggressive pathogen 10.3.2.4.8 High reproductive capacity of the Pathogen 10.3.2.5 Fecundity of pathogen 10.3.2.6 Numerical threshold of infection 10.3.2.7 Rhythm of successive generations 10.3.2.8 Ready dissemination of pathogen 10.3.2.9 Unexacting growth requirements of Pathogen 10.3.2.10 Optimal weather condition (Meteoropathology) 10.3.2.11 Cause of the progressive severity of epidemics 10.3.2.12 Conditions for decline of epidemic 10.3.2.13 Saturation of host population by disease 10.3.2.14 Reduction in disease proneness of host plants 10.3.2.15 Decreased in vitality of the pathogen 10.3.3 Plant disease forecasting 10.3.3.1 Forecasting Methods 10.3.3.2 Methods of disease forecasting may be 10.3.4 Disease triangle 10.3.5 Disease cycle 10.3.5.1 Stages of Development 10.3.5.2 Reproduction 10.3.5.3 Survival 10.3.5.3.1 Monocyclic Plant Disease 10.3.5.3.2 Polycyclic Plant Disease 10.4 Answer to Check Your Progress Questions 10.5 Summary 10.6 Key Words 10.7 Self Assessment Question and Exercises 10.8 Further Reading BLOCK 4: HOST- PATHOGEN INTERACTIONS AND PLANT DISEASES UNIT – XI HOST-PATHOGEN INTERACTION 1 2 8-147 11.1 Introduction 11.2 Objectives 11.3 Host-pathogen Interactions 11.3.1 Introduction to Host-pathogen Interactions 11.3.2 Infection Process 11.3.3 Adhesion 11.3.4 Penetration 11.3.4.1 Direct Penetration 11.3.4.2 Mechanical Forces 11.3.4.2.1 Exerted on Host Tissues by Pathogens 11.3.4.3 Chemical Forces 11.3.4.3.1 Weapons of Pathogens 11.3.4.3.1.1 Enzymes 11.3.4.3.1.2 Toxins 11.3.4.3.1.3 Growth Regulators 11.3.4.3.1.4 Polysaccharides 11.3.5 Colonization 11.4 Defense Mechanisms in plants 11.4.1 Introduction 11.4.2 Pathogenesis and Host Response 11.4.3 Pre existing or Pre-Infective Defense Mechanism 11.4.4 Biochemical Barriers 11.4.5 Post Infective or Induced Defense Mechanism 11.4.5.1 Induced Physical or Structural or Histological Barriers 11.4.5.2 Induced Biochemical Changes 11.5 Answer to Check Your Progress Questions 11.6 Summary 11.7 Key Words 11.8 Self Assessment Question and Exercises 11.9 Further Reading UNIT – XII CONTROL MEASURES 148-174 12.1 Introduction 12.2 Objectives 12.3 Cultural Practices 12.3.1 Introduction 12.3.2 Cultural methods 12.3.2.1 Eradication 12.3.2.1.1 Eradication of alternate hosts 12.3.2.1.2 Eradication of collateral and self-sown overwintering hosts 12.3.2.1.3 Eradication of affected plants or trees 12.3.2.1.4 Eradication of pathogens from infected plant parts by surgery 12.3.2.2 Crop rotation 12.3.2.3 Fallowing 12.3.2.4 Application of organic
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