222 



PHYSIOLOGY OF THE FUNGI 



noniella echinata (the variability in strains in laboratory tests is possibly 

 correlated with biotin deficiency), Chaetomium spp., especially C. glo- 

 bosian (Greathouse and Ames, 1945), Myrothecium verrucaria (as strong 

 a cellulose decomposer as yet found in laboratory tests), Trichoderma 

 viride, and Thielavia sepedonium. 



The reduction in tensile strength of cotton duck maintained under 

 specified conditions is used as a measure of the destructive effects of 

 fungi on fabrics. The data in Table 38 are taken from White et al. (1948). 



Table 38. 



Assay of Fungi for Cellulolytic Activity Based upon Loss of 

 Tensile Strength of Cotton Duck 

 (White et al, Mrjcologia 40, 1948.) 



Species 



Aspergillus niger PQMD 25a 



A. terreus PQMD 72f 



Chaetomium funicolum PQMD 351. 



C. globosum PQMD 32b 



Fusarium oxysponim Fla C-8 



Gliomastix convoluta PQMD 4c 



Myrothecium verrucaria PQMD 70h 

 Thielavia sepedonium PQMD 47g. . 



Trichoderma viride PQMD 6a 



T. viride PQMD 63d 



Growth 



at end of 



experiment 



2 



4 

 4 

 4 

 3 

 4 

 4 

 4 

 4 

 



The evaluation of protective fungicides for fabrics, paper, and other 

 cellulosic materials consists in comparing the effects of known cellulolytic 

 fungi upon treated and untreated specimens of material. In addition 

 to causing loss of tensile strength, some fungi cause great damage by 

 surface growth (mildew). Abrams (1948) has reviewed the techniques 

 used at the Bureau of Standards for testing mildew- and rotproofing 

 agents. Aspergillus niger was used to determine mildew resistance, and 

 the effectiveness of various treatments was evaluated by visual observa- 

 tion. Chaetomium globosum and a species of Penicillium (USDA 66) 

 were used in rot-resistance tests. Of some 36 compounds tested, copper 

 naphthenate and pyridyl mercury compounds were most effective. The 

 effectiveness of the fungicides varies with the test organisms used. For 

 data on fungicide evaluation the reader is referred to Abrams (1948). 



SUMMARY 



The use of microorganisms for analytical purposes is based upon specific 

 biochemical characteristics of selected test organisms. Within a certain 

 range of concentration, the response is proportional to the amount of 



