CONTENTS Xlll 



Page 



6. Nutrition and Germination 400 



7. pH and Germination 403 



8. Water and Germination 404 



9. Temperature and Germination 407 



10. Oxygen and Germination 412 



11. Carbon Dioxide and Germination 413 



12. Biological Effects on Spore Germination 413 

 Bibliography 415 



Chapter 13 The Action of Physical Agents 423 



1. High Temperature 423 



2. Low Temperature 425 



3. Visible Light 427 



4. Ultraviolet Radiation 429 



5. Ionizing Radiations 433 



6. Electromagnetic Radiation of Long Wavelength 435 

 Bibliography 435 



14 The Action of Chemical Agents 440 



1. The Response to Toxicants and Its Measurement 441 



2. Tolerance and Resistance 448 



3. Selective Accumulation 450 



4. Surface Action 453 



5. Hydrogen-Ion Concentration 454 



6. Structure and Activity 457 



7. The Action of Heavy Metals 465 



8. The Action of Sulfur 472 



9. Quinones and Other Unsaturated Compounds 475 

 10. Chelation and Fungistatic Activity 478 



Bibliography 485 



Organism Index 499 



Subject Index 508 



v mass. SS^j 



