CONTENTS 

 PART I 



INTRODUCTION : 



THE NATURE AND CLASSIFICATION OF PLANT DISEASES 



SECTION I.— CAUSATION 



CHAPTER I : DISEASES CAUSED BY FUNGI. 



The Nature of Fungi. Page 



The Mycelium. The Place of Fungi in Nature- - - 3 



The Nature of Fungus Parasitism ----- 5 



Reproduction and Infection ___-_- 6 



The Host : Resistance and Susceptibility. 



Effect of Agricultural Conditions on Resistance. Immunity 

 by Evasion. Resistant Species or Varieties. Susceptibility 

 to Exotic Diseases. Local Factors affecting Prevalence - 8 



The Principal Types of Fungus Diseases. 



Leaf Diseases. Flower and Fruit Diseases. Stem Diseases. 



Root Diseases --------- 12 



Notable Groups concerned in Fungus Diseases. 



The Rusts (Uredinales). The Smuts (Ustilaginales). The 

 Powdery Mildews (Erysiphaceae). The Downy Mildews 

 (Phytophthora). The Anthracnoses. The Fusariums. The 

 Diplodias. The Rhizoctonias. The genus Marasmius. The 

 Fungi infecting Bug Punctures (Stigmatomycosis). The 

 Sooty Moulds (Capnodiae) - - - - - - 17 



The Classification of Fungi ------ 34 



CHAPTER II : DISEASES CAUSED BY BACTERIA - - 45 



CHAPTER III : DISEASES CAUSED BY INFECTIVE VIRUSES 48 

 CHAPTER IV: PHANEROGAMIC PARASITES. 



Love Vine, Vermicelle ------- 54 



Cassytha _-___---- 56 



Bird Vine, Mistletoe __---__ 56 



Alectra, Cane-Killer ---____ 58 



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