plant disease

Table of Contents

Introduction
General considerations
- Nature and importance of plant diseases
  - Diseases—a normal part of nature
  - Definitions of plant disease
- Disease development and transmission
  - Pathogenesis and saprogenesis
  - Epiphytotics
  - Environmental factors affecting disease development
    - Temperature
    - Relative humidity
    - Soil moisture
    - Soil pH
    - Soil type
    - Soil fertility
  - Requirements for disease development
- Diagnosis of plant diseases
  - Variable factors affecting diagnosis
  - Symptoms
  - Signs
  - Technological advances in the identification of pathogenic agents
- Principles of disease control
  - Exclusion and avoidance
  - Eradication
  - Protection
    - Regulation of the environment
    - Cultural practices
    - Regulation of fertility level and nutrient balance
    - Handling practices
    - Control of insect vectors
    - Chemical control
    - Biological control
  - Therapy
  - Host resistance and selection
    - Variable resistance
    - Obtaining disease-resistant plants
    - The use of genetic engineering in developing disease-resistant plants
Classification of plant diseases by causal agent
- Noninfectious disease-causing agents
  - Adverse environment
  - Toxic chemicals
  - Physical injury
- Infectious disease-causing agents
  - Diseases caused by viruses and viroids
    - General characteristics
    - Symptoms
    - Transmission
    - Control
  - Diseases caused by bacteria
    - General characteristics
    - Symptoms and signs
    - Transmission and infection
    - Control
  - Diseases caused by fungi
    - General characteristics
    - Symptoms and signs
    - Transmission
    - Control
  - Diseases caused by nematodes
    - Mode of nematode attack
    - Nematode diseases
    - Control measures
  - Parasitic seed plants
    - Mistletoe
    - Dodder
    - Witchweed

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plant disease: Related Content

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Photos and Videos

Tomato leaves puckered and blistered by the tobacco mosaic virus.

Cysts or tiny nodes on soybean plant roots, containing eggs of nematodes.

parasitic dodder

ozone damage on leaf

Understand how plants are infected by diseases through rainwater droplet splashing from leaf to leaf

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