1 1 . Reproduction 



X 



.he attention of those interested in physiological as- 

 pects of the reproductive process in fungi has been focused almost 

 exclusively on the problem of the initiation of sporulation, and these 

 studies occupy the bulk of this chapter. The further development of 

 the reproductive structures has in the main been treated as a problem 

 in morphology, and, with some exceptions, its physiological and bio- 

 chemical determinants are unknown. 



Naturally enough, any physiological study tends to emphasize the 

 one or two factors in reproduction which are manipulated by the ex- 

 perimenter. It should, of course, be obvious that reproduction requires 

 that all genetic and environmental factors be favorable. This com- 

 plexity is particularly apparent in ecological studies of the higher 

 fungi (115). 



Although some tentative conclusions on fungi in general have been 

 proposed, it should be emphasized that any organism must be studied 

 individually; there is no one "formula" for sporulation. 



It is fair to say that most of our knowledge of reproduction in the 

 fungi comes from essentially qualitative data. Sporulation occurs 

 under some conditions, but not under others, and data may be re- 

 ported in simple "yes" or "no" categories. No objection can be made 

 to this procedure in general; however, it is becoming clear that some 

 problems require quantitative data on the intensity of sporulation. 

 This is particularly true of nutritional studies, in which the response 

 is likely to be quantitative rather than all-or-none. 



It has not been possible, with present information, to consider the 

 physiology of resting structures, e.g., chlamydospores and sclerotia, 

 separately or in detail. Chlamydospore formation is probably a re- 

 sponse to unfavorable environmental conditions (214, 215, 231, 266). 



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