plant disease

• What can cause disease in plants?


  • bacteria
  • fungi
  • viruses
  • deficiencys
  • vectors
• How can plant disease be identified?

  • Damaged leaves
  • patches of discolouration - surface area for photosynthesis decreases
  • stunted growth
  • malformed leaves and stems and or growths
  • pests may even be present
• How can you identify different plant diseases?

  • Reference to a garden manual or online source
  • use test kits which contain monoclonal antibodies
  • take plants to a lab to identify pathogen
• How could they study a plant disease in a lab?

  • MICROSCOPY - look at a tissue sample in a microscope
  • CULTURE - culture pathogens on agar plate and use DNA ANALYSIS
• What can a plant have a defficiancy in?

  • Nitrates
  • Phosphates
  • Magnesium
• What happens if a plant is deficiant in Mg?

  • Mg is used to make chlorophyll
  • Chlorosis - yellow leaves and stunted growth
• What happens if a plant is deficiant in nitrates?

  • Used to make proteins
  • Poor growth
• What happens if a plant is deficiant in phosphates?

  • Purple, curled up leaves
• How can plants PHYSICALLY prevent disease?

  • Waxy cuticle
  • Tree bark
  • Cellylose cell wall
• How can plants prevent disease CHEMICALLY?

  • Chemicals secreted; antifungal, antibacterial, poisons (to deter herbivors)
• How can plants defend disease MECHANICALLY?

  • (prevent animals touching them)
  • Hairs and thorns
  • Moving leaves - some plants curl up when they are touched
  • Mimicry - some plants adapted to look like other dangerous plants