Plant disease and defences

• What will be covered in the video?

  Plant diseases and their defenses
• From what can plants catch diseases?

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

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

  Diseases from 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 experience stunted growth
• What role do magnesium ions play in plants?

  They are needed for making chlorophyll
• What symptom indicates magnesium deficiency in plants?

  Chlorosis and yellow leaves
• What are some symptoms of diseased plants?

  Abnormal growths, decay, 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 specialize in?

  Plant diseases and their diagnosis
• What detailed testing can a plant pathologist perform?

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

  They identify specific pathogens present
• What is one method of trial and error for diagnosing plant issues?

  Adding magnesium for yellow leaves
• What are the three types of plant defenses?

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

  Secrete antimicrobial substances or poisons
• What common drug is derived from plant chemicals?

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

  Structures that deter animals from feeding
• How do thorns function as a plant defense?

  They prevent animals from eating plants
• What happens to leaves that curl or droop?

  They react to insects landing on them
• What are the main types of plant defenses against diseases?

  • Physical defenses: Waxy cuticle, cell walls
  • Chemical defenses: Antimicrobial substances, poisons
  • Mechanical defenses: Thorns, hairs, curling leaves
• What are the steps to diagnose a plant disease?

  1. Observe symptoms
  2. Match symptoms to a manual
  3. Send sample to a pathologist if needed
  4. Conduct trial and error methods