Plant Pathology Module 1

1. Father of Plant Pathology – Anton de Bary (1863)
2. Father of Indian Plant Pathology – J. Butler
3. First plant disease recorded – Wheat rust (300 BC)
4. First bacterial disease – Fire blight of apple (Erwin F. Smith, 1878)
5. First viral disease – Tobacco Mosaic Virus (TMV)
6. TMV discovered by – Ivanowsky (1892)
7. TMV crystallized by – Stanley (1935)
8. First fungicide discovered – Bordeaux mixture (Millardet, 1885)
9. Bordeaux mixture composition – CuSO₄ + Ca(OH)₂
10. Robert Koch (1876) gave Koch’s postulates for disease diagnosis.
11. Arnon & Stout (1939) gave criteria of essentiality for nutrients.
12. Flor (1942) proposed the Gene-for-Gene
13. Late blight of potato caused Irish famine in 1845.
14. Phytophthora infestans causes late blight of potato.
15. Puccinia graminis tritici causes black rust of wheat.
16. Ustilago tritici causes loose smut of wheat.
17. Karnal bunt of wheat is caused by Tilletia indica.
18. Tundu disease of wheat is caused by Anguina tritici + Corynebacterium tritici.
19. Red rot of sugarcane – Colletotrichum falcatum.
20. Smut of sugarcane – Ustilago scitaminea.
21. Sheath blight of rice – Rhizoctonia solani.
22. Blast of rice – Pyricularia oryzae / Magnaporthe grisea.
23. Bacterial leaf blight of rice – Xanthomonas oryzae pv. oryzae.
24. Leaf curl of cotton – transmitted by whitefly.
25. Citrus canker – Xanthomonas axonopodis pv. citri.
26. Citrus tristeza virus transmitted by Toxoptera citricida (aphid).
27. Tikka disease of groundnut – Cercospora arachidicola.
28. Wilt of cotton – Fusarium oxysporum f.sp. vasinfectum.
29. Wilt of pigeon pea – Fusarium udum.
30. Wilt of tomato – Fusarium oxysporum f.sp. lycopersici.
31. Root-knot of tomato – Meloidogyne incognita.
32. Ring rot of potato – Clavibacter michiganensis subsp. sepedonicus.
33. Soft rot of vegetables – Erwinia carotovora.
34. Club root of cabbage – Plasmodiophora brassicae.
35. Downy mildew of bajra – Sclerospora graminicola.
36. Downy mildew of grapes – Plasmopara viticola.
37. Powdery mildew of pea – Erysiphe polygoni.
38. Ergot of bajra – Claviceps fusiformis.
39. Ergot of rye – Claviceps purpurea.
40. Ergot alkaloid causes ergotism in humans.
41. Green ear disease of bajra – Sclerospora graminicola.
42. Smut of bajra – Tolyposporium penicillariae.
43. Early blight of potato – Alternaria solani.
44. Leaf spot of turmeric – Colletotrichum capsici.
45. Red rot of sugarcane – diagnostic red patches with white zones.
46. Panama wilt of banana – Fusarium oxysporum f.sp. cubense.
47. Bunchy top of banana – transmitted by Pentalonia nigronervosa (aphid).
48. Papaya leaf curl – transmitted by whitefly.
49. Mosaic disease of sugarcane – transmitted by aphids.
50. Little leaf of brinjal – caused by
51. Sandal spike disease – caused by
52. Sesame phyllody – caused by
53. Potato spindle tuber disease – caused by
54. Viroids discovered by Diener (1971).
55. Mycoplasma-like organisms (MLOs) cause diseases without cell walls.
56. Nematode causing ear-cockle in wheat – Anguina tritici.
57. White tip of rice – Aphelenchoides besseyi.
58. Root-knot nematode – Meloidogyne incognita.
59. Cyst nematode of potato – Globodera rostochiensis.
60. Vector of rice tungro virus – Nephotettix virescens.
61. ELISA and PCR are used for virus detection.
62. Trichoderma viride and Pseudomonas fluorescens – biocontrol agents.
63. Seed treatment fungicides – Captan, Thiram, Carbendazim.
64. Systemic fungicides – Carbendazim, Propiconazole.
65. Contact fungicides – Mancozeb, Copper oxychloride.
66. Antibiotic used in plant disease control – Streptomycin.
67. Fungus causing downy mildew belongs to class Oomycetes.
68. Fungus causing powdery mildew belongs to class Ascomycetes.
69. Rusts and smuts belong to class Basidiomycetes.
70. Wilt fungi belong to class Deuteromycetes.
71. Disease triangle consists of Host, Pathogen, and Environment.
72. Epidemic triangle adds time as the fourth factor.
73. Inoculum is the part of the pathogen causing infection.
74. Incubation period – time between infection and symptom appearance.
75. Hypersensitive reaction – rapid cell death around infection site.
76. Phytoalexins – antimicrobial compounds produced by plants.
77. Example of phytoalexin: Pisatin in pea.
78. Vector of cotton leaf curl virus: Whitefly (Bemisia tabaci).
79. Fungicide for seed-borne disease control:
80. Bacterial ooze test is used for bacterial wilt identification.
81. Fungal spores germinate in presence of free water.
82. Zoospores are motile spores found in lower fungi.
83. Pycnidium is an asexual fruiting body of fungi.
84. Perithecium and Cleistothecium are sexual fruiting bodies.
85. Obligate parasites cannot grow on artificial media.
86. Facultative saprophytes – usually parasitic but can live saprophytically.
87. Facultative parasites – usually saprophytic but can become parasitic.
88. Bacterial diseases show water-soaked lesions.
89. Viral diseases show mosaic, curling, stunting, and yellowing.
90. Phytoplasma diseases show witches’ broom, phyllody, little leaf.
91. Fungal diseases show spots, rots, wilts, smuts, and mildews.
92. Downy mildew thrives under high humidity & low temperature.
93. Powdery mildew thrives under low humidity & warm climate.
94. Ergot disease produces toxic alkaloids.
95. Rust spores (uredospores) are red or brown colored.
96. Teliospores – thick-walled resting spores of rust fungi.
97. Chlamydospores – resting spores of
98. Appressorium – infection structure in
99. Bacteriophage – virus that infects bacteria.
100. Sanitation, rotation, and resistant varieties are key for disease prevention.