1. Diseases
Help me! I’m dying.

2. Disease
Disease is a plant disorder caused by an infectious pathogen or agent
Host – Plant the disease attacks
Pathogen – Any disease causing agent
Environment – moisture and temperature needed for the pathogen to grow

3. Groups of pathogens Bacteria Fungi Viruses Parasitic plants-
Single-celled organism
Must remain in host or under debris
Actively divide to spread
Fungi
Multi-cellular
Eats on plants and hurts them in the process
Produces spores that spread
Viruses
Ultramicroscopic parisites
Attack plant tissues
Should destroy plant completely if found
Parasitic plants-
A plant that attaches to another plant
Ex. mistletoe, dodder, lichens

4. Plant Disease Must be identified before they can be treated
Warm temperatures and moist conditions in greenhouse plant production make most horticulture plant diseases worse

5. Disease
Preventing plant disease through sanitation and insect control is much easier than treating the disease.

6. Diseases Blight Canker sores Damping off Galls Leaf spot Mildew Mosaic
Rots
Rust
Smut
Wilt

7. Blight Infectious bacterium
Cause plant to quickly turn brown or black as if they had been burned
One specific blight is fire blight-devastating apple crops
Prune 6-8” below infection

8. Canker
Bacterial disease
Causes open wounds on woody plant stems

9. Damping off Fungal disease
Causes young plants and seedling to rot off at soil level
Need clean containers and soil and plenty of air circulation between plants

10. Galls Round swelling or growths on plants
Usually caused by an insect that vectors the disease

11. Leaf spot Rings of different shades of brown, green, or yellow
Looks like dots or circles

12. Mildew Fungus Grows on leaf surfaces
Appears as white, gray or purple spots
Example is powdery mildew
Homemade remedy= 2 tsp baking soda + horticultural oil with 1 gal water

13. Mosaic Caused by a virus
Leaves have irregular mottled areas with patterns
Ranges from dark green to light green to yellow to white
Tomato mosaic virus is common in tomatoes

14. Rots Fungus Causes plants to decay and die Usually has a unique smell
Improve drainage for the plant to prevent

15. Rust Fungus Causes small spots on leaves
Resembles yellow, orange, brown or red rust
Mainly on underneath of leaf

16. Smut Black powdery disease Causes blisters that burst open
Releases black spores
Grows on aphid’s honeydew

17. Wilt Fungus Disease that blocks the uptake of water in plants stems
Causes plants to look constantly wilted even when adequately watered