plant defences and diseases

• What will be covered in this video?

  Plant diseases and their defenses
• How can plants catch diseases?

  From microorganisms and larger organisms
• What are some microorganisms that can cause plant diseases?

  Fungi, bacteria, and viruses
• What are deficiency diseases in plants?

  Diseases caused by lack of essential minerals
• Which essential minerals are mentioned for plant health?

  Nitrates and magnesium ions
• Why are nitrates important for plants?

  They are needed for making proteins
• What happens to plants with insufficient nitrates?

  They often exhibit stunted growth
• What role do magnesium ions play in plants?

  They are needed for making chlorophyll
• What is a symptom of magnesium deficiency in plants?

  Yellow leaves due to chlorosis
• What are some symptoms of diseased plants?

  Abnormal growths, lumps, and discoloration
• How can you identify the organism responsible for plant disease?

  By observing visible organisms like aphids
• What is the easiest method to diagnose plant disease?

  Match symptoms to a garden manual
• What can you do if basic observations fail to diagnose a plant disease?

  Send a sample to a plant pathologist
• What does a plant pathologist do?

  Specializes in diagnosing plant diseases
• What is one method a plant pathologist might use for diagnosis?

  Look at tissue samples under a microscope
• How can unique antigens help in diagnosing plant diseases?

  They identify specific pathogens present
• What is a basic method for diagnosing plant issues?

  Trial and error with treatments
• What is a benefit of the trial and error method?

  You can try one treatment at a time
• What are the three types of plant defenses?

  Physical, chemical, and mechanical
• What do physical defenses in plants do?

  Prevent entry of pathogens
• What are chemical defenses in plants?

  Chemicals that kill or deter pathogens
• What is a well-known drug derived from plant chemicals?

  Aspirin from willow trees
• What are mechanical defenses in plants?

  Defenses that deter animals from feeding
• How do some leaves respond to insect landings?

  They curl or droop to deter insects
• What are the main types of plant defenses against diseases?

  • Physical defenses: prevent pathogen entry
  • Chemical defenses: secrete antimicrobial substances
  • Mechanical defenses: deter animals with thorns or hairs
• What are the symptoms of plant diseases?

  • Abnormal growths or lumps
  • Malformed stems or leaves
  • Patches of decay or discoloration
  • Yellow leaves due to chlorosis
• How can you diagnose a plant disease effectively?

  1. Observe symptoms
  2. Match symptoms to a manual
  3. Send samples to a pathologist if needed
  4. Use trial and error with treatments