Chapter 25 



FUNGI AND PLANT DISEASE 



Plant diseases are nothing new to mankind. The ancient 

 Hebrews, in their bibhcal writings, frequently mention rusts, 

 mildews, and blights of their crops. Aristotle, Pliny, and The- 

 ophrastus mention diseases of the olive, fig, and grape, the most 

 valued of the Greek's cultivated plants. In ancient times these 

 plant maladies were attributed to the doings of some god or gods 

 whose disfavor the people had incurred. To appease the wrath 

 of such a diety and thus protect coming crops from damage, 

 offerings of fruits and cereals were made at various times. Such 

 superstitious beliefs regarding the nature and cause of plant 

 disease persisted until the middle of the nineteenth century. 



Modern plant pathology, or the study of plant disease, has 

 found more specific causes, classifying plant diseases according 

 to the nature of the causal organism. The invention and im- 

 provements of the microscope and methods of preparing plant 

 tissues for microscopic examination have resulted in the gather- 

 ing of much information concerning the nature, functions, and 

 methods of attack of man's many destructive plant diseases. 

 Information on the detection and control of these is disseminated 

 by federal and state agricultural departments. 



Fungi have existed as parasites of the green plants for many 

 hundreds of thousands of years, exacting a yearly toll from them 

 in the wild state long before man took them into his agriculture. 

 By growing such plants in great numbers, man off'ers the fungi 

 a great opportunity for rapid growth and reproduction, so that 

 as he becomes more and more dependent upon cultivated crops 

 for his food and clothing supplies, he must be ever more watchful 

 for the invasion of plant diseases. Many historical records of 

 misery and starvation picture the ravages of fungi. The famous 

 ERGOT poisoning due to the eating of cereal grains, especially 



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