Fungal and Protist Diseases

Fungal Diseases

• Fungi and protists are important pathogens, though less known than bacteria and viruses.
• Fungal diseases affecting humans are relatively few.
  • Athlete's foot is a common, minor skin condition.
  • Some fungal diseases can be fatal if they attack the lungs or brains, particularly in already ill individuals.
  • Damaged heart valves can develop serious fungal infections, but these are rare.
  • Antifungal drugs are effective against skin fungi, but deep-seated tissue infections are harder to treat.
• Fungal diseases are common and devastating in plants.
  • Huge crop losses occur annually due to fungal infections like stem rusts and rotting diseases, affecting cereals and bananas.

Rose Black Spot

• Rose black spot is a fungal disease affecting rose leaves, causing purple or black spots.
• It is a nuisance for gardeners and commercial flower growers.
• Leaves often turn yellow and drop early, weakening the plant by reducing photosynthesis.
• Reduced photosynthesis leads to poor flowering, which is the main reason for growing roses.
• The spores spread via wind and water (splashing from one leaf to another during rain).
• Spores remain dormant over winter on dead leaves and stems.
• Prevention methods:
  • Removing and burning affected leaves and stems.
  • Using chemical fungicides.
  • Horticulturists have bred roses with resistance to black spot, but the disease cannot be fully prevented or cured.

Diseases Caused by Protists

• Protists are single-celled organisms that cause various diseases in animals and plants.
• They are relatively rare pathogens, but the diseases they cause are often serious.
• These diseases usually involve a vector that transfers the protist to the host.
• Malaria is a well-known and globally serious protist disease.

Malaria

• Malaria is caused by protist pathogens that are parasites (living and feeding on other organisms).
• The life cycle includes time in the human body and in the body of a female Anopheles mosquito.
• The mosquito transfers the protist to the human host.
• Symptoms include bouts of fever, and malaria can be fatal if untreated.