1. Plant Pathology David R. Drake

2. Pathology The study of disease. Disease Anything that causes abnormal growth

3. Plant Disease Any disturbance of a plant that interferes with its normal growth and development, economic value, and aesthetic quality; a continuously, often progressively affected condition in contrast to injury, which results from momentary damage. Source: Plant Diseases: Their Biology and Social Impact. Gail L. Schumann APS Press

4. Historical Plant Diseases Irish Potato Famine American Chestnut Blight Dutch Elm Disease. St. Anthony’s Fire Tulip Virus

5. St. Anthony’s Fire Ergot Prevalent in Rye

7. Tulip Virus Tulips introduced to Europe circa 1550 Virus infected bulbs created Tulipmania from 1634-37.

8. PRICE BARTERED FOR 1 BULB 4 Tons Wheat 8 Tons Rye 4 Fat Oxen 8 Fat Pigs 12 Fat Sheep 2 Hogsheads Wine 4 Barrels Beer 2 Barrels Butter 1000 Lbs Cheese 1 Bed with Accessories 1 Full-dress Suit 1 Silver Goblet

10. Types of Pathogens Parasitic Non-parasitic (abiotic)

11. Pathogen Host Environment Factors in Disease: Disease Triangle

12. Parasitic Fungi Bacteria Virus Nematodes protoplasma Parasitic plants

13. Fungi Lack cholorphyll 100,100 – beneficial Most microscopic Spores Fungicides

19. Bacteria Single-celled Binary fission Rapid multiplication Free moisture Bactericides

21. Virus Protein and nucleic acid Sub-microscopic Insect vectored Mechanical transmission

25. Nematodes Microscopic eel worms Eggs Stylet Virus vectors Nematicide

27. Protoplasma (mycoplasma) Similar to bacteria No cell wall Vectored by leafhoppers Controlled with antibiotics

30. Parasitic Plants

31. Dodder

34. Non-parasitic Iron chlorosis Powdery mildew Cytospora Fire blight

36. Iron Chlorosis

49. Powdery Mildew Halt (thiophanate methyl) Benlate Funginex Bayleton Sulfur Tilt

52. Funginex Roses – Powdery mildew – Rust (rare) Fruit – Powdery mildew – Brown rot (rare)

53. Cytospora Canker

58. Fire Blight

62. Fire Blight Control Avoid excess nitrogen Prune out cankers Treat with fixed copper or streptomycin

65. Cuitlachoche Safflower oil Onion chopped Garlic chopped Chilies Cuitalchoche 3T 2T 2 4 4 Cups Saute’ until translucent

78. Verticillium Wilt

82. Chlorothalonil Disease control with Daconil Daconil lawn and garden fungicide Daconil 2787 Multi-purpose fungicide

83. White Mold

86. Slime Flux Wet Wood