178 



PHYSIOLOGY OF THE FUNGI 



was attained in 20 days, while, in medium lacking thiamine, the fungus 

 required approximately 40 days to reach the maximum weight. This is 

 attributed to the slow rate of synthesis of thiamine. Other isolates of 

 L. trahea showed varying degrees of partial deficiency (Lilly and Barnett, 

 1948). 



Single and multiple deficiencies. The above discussion has dealt with 

 examples of single deficiencies (for a single vitamin). For example, 

 Sordaria fimicola is deficient only for biotin (Fig. 31), Lenzites trahea. 



EO 30 40 



Incubation (days) 



Fig. 34. Growth of a haploid isolate of Lenzites trahea and change in pH of liquid 

 glucose-casein hydrolysate medium at 25°C., with and witliout the addition of 

 thiamine. These curves illustrate a partial deficiency for thiamine. (After Lilly and 

 Barnett, Jour. Agr. Research 77: 290, 1948.) 



Ceratostomella Hmhriata (Fig. 31), and Phycomyces blakesleeanus for 

 thiamine only. On the other hand, some fungi have multiple deficiencies 

 (for two or more vitamins). These may be total or partial. An illustra- 

 tion of multiple deficiency is furnished by Sclerotinia camelliae (Fig. 35). 

 Little or no growth occurred on vitamin-free medium or that containing 

 either thiamine or biotin alone; the fungus grew well only in media con- 

 taining both thiamine and biotin. When inositol also was added, growth 

 was consistently better than in the presence of the two vitamins. This 

 indicates a partial deficiency for inositol, in addition to the total, or near 

 total, deficiencies for thiamine and biotin. Pyridoxine, when added to 

 the other three vitamins, had little or no effect on growth under these 

 conditions. 



Other examples of multiple vitamin deficiencies are common. Pleurage 

 curvicolla (Fig. 31), Chaetomium convolutum, Coemansia interrupta, and 



