2. Plant pathology by Prof. Dr. Amany Abo Ellil Prof. Dr. Amany Abo Ellil

3. Part III Fungal diseases Introduction Introduction Characteristics of plant pathogenic fungi Characteristics of plant pathogenic fungi Classification of plant pathogenic fungi Classification of plant pathogenic fungi Diseases caused by Fungal Like Organisms Diseases caused by Fungal Like Organisms Diseased caused by Myxomycota Diseased caused by Myxomycota Diseased caused by Plasmodiophoromycetes Diseased caused by Plasmodiophoromycetes Diseased caused by Oomycets Diseased caused by Oomycets Diseases caused by True Fungi Diseases caused by True Fungi Diseased caused by Chytridiomycota Diseased caused by Chytridiomycota Diseased caused by Zygomycota Diseased caused by Zygomycota Diseased caused by Ascomycota Diseased caused by Ascomycota Diseased caused by Basidiomycota Diseased caused by Basidiomycota Diseased caused by Deuteromycota Diseased caused by Deuteromycota

4. Introduction Fungi are small, generally microscopic, eukaryotic, usually filamentous, branched, spore – bearing organisms that lack chlorophyll. Fungi are small, generally microscopic, eukaryotic, usually filamentous, branched, spore – bearing organisms that lack chlorophyll. Fungi have cell walls that contain chitin and glucans (but no cellulose) as the skeletal components. Fungi have cell walls that contain chitin and glucans (but no cellulose) as the skeletal components. These are embedded in a matrix of polysaccharides and glycoproteins. These are embedded in a matrix of polysaccharides and glycoproteins.

5. Ecology Almost all plant pathogenic fungi spend part of their lives on their host plants and part in the soil or in plant debris on the soil. Almost all plant pathogenic fungi spend part of their lives on their host plants and part in the soil or in plant debris on the soil. Biotrophs Biotrophs Hemibiotrophs Hemibiotrophs Facultative saprophytes Facultative saprophytes Facultative parasites Facultative parasites

6. During the parasitic phase, fungi assume various positions in relation to the plant cells and tissues. During the parasitic phase, fungi assume various positions in relation to the plant cells and tissues.

7. Reproductive bodies [spore] are produced at or very near to surface ensure their prompt and efficient dissemination. Reproductive bodies [spore] are produced at or very near to surface ensure their prompt and efficient dissemination.

8. Overseason Overseason

9. Dissemination Dissemination Active Active Passive Passive

10. Classification of plant pathogenic fungi Fungal-like organisms Fungal-like organisms Kingdom: Protozoa Kingdom: Protozoa Phylum: Myxomycota Phylum: Myxomycota Phylum: Plasmodiophoromycota Phylum: Plasmodiophoromycota Kingdom: Cromista Kingdom: Cromista Phylum: Oomycetes Phylum: Oomycetes

11. Kingdom: True Fungi Kingdom: True Fungi Phylum: Chytridiomycota Phylum: Chytridiomycota Phylum: Zygomycota Phylum: Zygomycota Phylum: Ascomycota Phylum: Ascomycota Phylum: Basidiomycota Phylum: Basidiomycota Phylum:Deuteromycota Phylum:Deuteromycota

12. Disease caused by fungal like organism Disease caused by myxomycota Disease caused by myxomycota [myxomycetes] [myxomycetes] Slime Mould Slime Mould Physarum Physarum Fuligo Fuligo Mucilago Mucilago Didymium Didymium

15. Diseases caused by Plasmodiophoromycota Club root of crucifers caused by Club root of crucifers caused by Plasmodiophora brassicae Plasmodiophora brassicae Root disease of cereals and grasses caused by Root disease of cereals and grasses caused by Polymyxa spp Polymyxa spp Powdery scab of potato caused by Powdery scab of potato caused by Spongospora subterranea Spongospora subterranea

19. Polymyxa graminis is vector of several viruses of grain crops,peanuts Polymyxa graminis is vector of several viruses of grain crops,peanuts P.betae is vector of beet necrotic yellow vein virus. P.betae is vector of beet necrotic yellow vein virus. Spongospora is vector of potato moptop virus. Spongospora is vector of potato moptop virus.

24. Diseases caused by Cromista Oomycota Oomycota Saprolegniales Saprolegniales Aphanomyces caused root rot; pea sugar beet Aphanomyces caused root rot; pea sugar beet Peronosporales. Peronosporales. Pythium caused seed rot; root rot; seedling damping off. Pythium caused seed rot; root rot; seedling damping off. Phytophthora caused late blight of potato ;root rot; fruit rot; stem rot; canker and diebacks of tree. Phytophthora caused late blight of potato ;root rot; fruit rot; stem rot; canker and diebacks of tree.

25. Prenospora; Bremia; Plasmopara Pseudopronospora caused downy mildew of cucurbits, lettuce, vitis, tobacco (dicot). Prenospora; Bremia; Plasmopara Pseudopronospora caused downy mildew of cucurbits, lettuce, vitis, tobacco (dicot). Peronosclerospora; sclerophthora ;Sclerospora caused downy mildew of corn; sorghum; sugar cane(mocot). Peronosclerospora; sclerophthora ;Sclerospora caused downy mildew of corn; sorghum; sugar cane(mocot). Albugo caused white rust of crucifers. Albugo caused white rust of crucifers.

26. Late blight of potato Symptoms Symptoms In moist weather In moist weather In dry weather In dry weather Pathogen: Phytophthora infestans Pathogen: Phytophthora infestans Mating type A1 and A2 Mating type A1 and A2

31. Development of disease Epidemic disease Epidemic disease Overwinter Overwinter Two Mating types Two Mating types Gene coding for enzyme(B-1,3 glucanase) defense related gene Gene coding for enzyme(B-1,3 glucanase) defense related gene Complex interest Complex interest

34. Control Control Combination of sanitary measures, resistant varieties and well time chemical spray may be obtain a satisfactory level of control of disease. Combination of sanitary measures, resistant varieties and well time chemical spray may be obtain a satisfactory level of control of disease. Systemic Acquired Resistance(SAR) by inducing DL3 amino-butyric acid or preinoculation with tobacco necrosis virus. Systemic Acquired Resistance(SAR) by inducing DL3 amino-butyric acid or preinoculation with tobacco necrosis virus.

35. Downy mildew Cromista Oomycetes prenosporaceae Cromista Oomycetes prenosporaceae Obligate parasite Catastrophic and Spectacular epidemic on cool or warm not hot weather. It needs a film of water and high relative humidity. Disease stops on hot and dry weather.

37. Pathogen causes systemic shoot infection in young plant. Pathogen causes systemic shoot infection in young plant. Pathogen causes local infection in old plant and locally systemic Infection in young tissue. Pathogen causes local infection in old plant and locally systemic Infection in young tissue. It destroys 40-90% of young plant It destroys 40-90% of young plant Severity losses of crop depend on cool & wet weather Severity losses of crop depend on cool & wet weather Ucontrollable Ucontrollable

38. Downy mildew Most common genera Bremia Bremia Haloperonospora Haloperonospora Peronospora Peronospora Peronosclerospora Peronosclerospora Plasmopara Plasmopara Pseudoperonospora Pseudoperonospora Sclerophthora Sclerophthora Sclerospora Sclerospora

39. Downy mildew of grape Plasmopara viticola Plasmopara viticola Most suscept is Vitis vinifera Most suscept is Vitis vinifera Severe losses through Severe losses through 1-killing of leaf and defoliation 1-killing of leaf and defoliation 2-low quality and entirely destroy grapes 2-low quality and entirely destroy grapes 3-weakening,dwarfing and killing of young shoot. 3-weakening,dwarfing and killing of young shoot.

40. Symptoms & signs

41. Small pale yellow Irregular Infected area killed White downy growth spots on upper surface turn brown underside of spot

42. Leatheary wrinkled reddish marbling to brown coloration

43. Plasmopara viticola In one season,it can easily destroy 50-70% of crop. In one season,it can easily destroy 50-70% of crop.

44. Development of disease Overwinter: oospore in dead plant and mycelium in infected but not killed twigs Overwinter: oospore in dead plant and mycelium in infected but not killed twigs First inoculum : sporangium or zoospore First inoculum : sporangium or zoospore Infection: through stoma and lenticels Infection: through stoma and lenticels Habitat: intercellular with haustoria Habitat: intercellular with haustoria Dissemination: by wind or water Dissemination: by wind or water Habit : biotrophs Habit : biotrophs Interest : complicated( 2ry infection cycle) Interest : complicated( 2ry infection cycle) Cycle spend 5-18 days depending on temp, humidity and varietal susceptibility Cycle spend 5-18 days depending on temp, humidity and varietal susceptibility Hot and dry stop disease development Hot and dry stop disease development 0

46. Control American grape varieties are resistant European grape vinifera is quite susceptible. American grape varieties are resistant European grape vinifera is quite susceptible. Protection by copper based fungicides,bordeaux mixture (broad spectrum protective fungicide). Protection by copper based fungicides,bordeaux mixture (broad spectrum protective fungicide). Application 7-10 days interval before blooming Application 7-10 days interval before blooming Disease prediction depends on duration of leaf wetness, relative humidity and temperature. Disease prediction depends on duration of leaf wetness, relative humidity and temperature.

47. Disease caused by True fungi Chytridiomcetes-Zygomycetes- Ascomycetes- Deuteromycetes- Basidiomycetes.

48. Disease caused by Ascomycota Disease caused by Ascomycota

49. Powdery Mildew Most common, wide spread affect all kinds of plant except gymnosperm

50. Obligate parasites

52. Powdery mildew of Rose Attack bud, young leaves & growing tips weakening of plant reduced flowers Attack bud, young leaves & growing tips weakening of plant reduced flowers

53. Powdery mildew seldom kill host utilize nutrient, reduce photosynthesis, increase respiration,transpiration impair growth & reduce yeild 20-40%.,

54. Ascomycota Erysiphales-Erysiphaceae 1-Blumeria graminis cearals & grasses 2- Erysiphe cichoracearum cucurbits, dahlia, zinnia E. polygonilegume, crucifers beets E. polygonilegume, crucifers beets E. betae beet E. betae beet E. orontii tomato E. orontii tomato 3- Leveillula tourica tomato 4- Microsphaera alni shady trees & woody orinamited 5- Oidium nelycopersicum tomato 6- phyllactinia shade forest trees Genera are distinguished by number of asci /cleistothecia and appendages growing of the wall of cleistothecia

55. Cleistotheia 0f powdery mildews

56. Pathogen Sphaerotheca pannosa rosae

57. Pathogen Sphaerotheca pannose rosae symptoms and signs On young leaves :…..curl distort ; on old leaves:….necrotic On shoot: white patches; cover terminal portion….curved and arched at tip; on bud before open fail to open; on flower discolored,dwarfed, die Plant Irritation,photosynthesis affected, bud opening is inhibited On young leaves :…..curl distort ; on old leaves:….necrotic On shoot: white patches; cover terminal portion….curved and arched at tip; on bud before open fail to open; on flower discolored,dwarfed, die Plant Irritation,photosynthesis affected, bud opening is inhibited

58. Development of disease Overwinter: cleistothecia at the end of season, mycelia or conidia in bud Overwinter: cleistothecia at the end of season, mycelia or conidia in bud Habitat: on surface of plant, with haustoria Habitat: on surface of plant, with haustoria Habit : biotrophs Habit : biotrophs 1 st inoculum :ascospore 1 st inoculum :ascospore Penetration: directly (haustoria through epidermis) Penetration: directly (haustoria through epidermis) Dissemination: by wind Dissemination: by wind Interest :complicated(2ry infection cycle) Interest :complicated(2ry infection cycle)

60. Control Fungicide: dusting by sulfur Fungicide: dusting by sulfur Systemic fungicides: sterol-inhibiting Systemic fungicides: sterol-inhibiting Resistant varieties in cereals Resistant varieties in cereals Biocontrol: Ampelomyces quisqualis Biocontrol: Ampelomyces quisqualis Using :phosphate –detergents-ultra fine oil- NaHCO3- Using :phosphate –detergents-ultra fine oil- NaHCO3- Using blue photosensitive polyethylene sheeting Using blue photosensitive polyethylene sheeting In cereals, chemical control is impractical difficult,not cost effect In cereals, chemical control is impractical difficult,not cost effect

62. Leaf curl Diseases caused by Taphrina Deformation on stone fruit, forest trees. leaf curl on peach & nectarine. leaf curl on peach & nectarine. Plum pocket on plums. Leaf curl on cherries. Witche’s-broom on cherries. Leaf blister of oak.

63. The pathogen Taphrina defomans

64. Symptoms Infected leaf thickened, distorted curled downward & inward. Became reddish purplish. Sporereddish yellow Powdery grey yellow brown Powdery grey yellow brown Infected blossoms & twigs fall early.

66. Plum :small white blister enlarged. entire fruit, abnormal in size entire fruit, abnormal in size distorted. distorted. Tissue: Flesh spongy. Seed ceases to develop turn brown. leaves and twigs may also affected.