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STUDIES IN THE PHYSIOLOGY OF THE FUNGI 



VII. Growth of Wood-Destroying Fungi on Liquid Media 



S. M. ZELLER, HENRY SCHMITZ, AND B. M. DUGGAR 



For some time this laborat 



has been conducting many- 



lines of investigation to determine various physiological fac- 

 tors influencing the growth and development of the wood-de- 

 stroying fungi. In this connection experiments have been un- 

 dertaken to determine (1) which fungi are adapted to growth 



liquid media 



hat liquid media are suitable t 



growth; and (3) the influence, if any, of the hydrogen ion con- 

 centrations of the media. To this end various media were 

 used. In three of these (Czapek's, Reed's, and Richards') the 

 H ion concentration was made to vary by using the mono-, 

 di-, and tribasic potassium phosphates in the different solu- 

 tions. 



The solutions used were as follows : 



1. Czapek's solution 1 which contains 0.5 gm. magnesium 

 sulphate, 1.0 gm. monobasic potassium phosphate, 0.5 gm. 

 potassium chloride, 0.01 gm. ferrous sulphate, 2.0 gms. sodium 

 nitrate, and 30 gms. cane sugar in 1000 cc. of water. 



2. Dunham's solution made up according to the usual 

 method, using 10 gms. bacto-peptone and 5 gms. sodium 

 chloride in 1000 cc. of water. 



3. A pine decoction prepared from the inner bark and outer 

 sap-wood of young twigs of Pinus Strobus. 



Ji,. Reed's solution 2 for the determination of cytase, which 

 contains 10 gms. ammonium nitrate, 5 gms. dibasic potassium 

 phosphate, 1 gm. magnesium sulphate, and 1 gm. sodium 

 citrate in 1000 cc. of ash-cellulose suspension in water. 3 



i Dox, A. W. The intracellular* enzymes of Penicillium and Aspergillus. 

 U. S. Dept. Agr., Bur. An. Intl. Bui. 120: 1-70. 1910. 



2 Reed, H. S. The enzyme activities involved in certain fruit diseases. Va. 

 Polytec. Inst., Agr. Exp. Sta. Rept. 1911-1912: 51-77. 1913. 



3 The method of preparing pure cellulose from ash wood was that described 

 by McBeth and Scales, U. S. Dept. Agr., Bur. PI. Ind. Bui. 266: 1-52. 1913. 



Ann. Mo. Bot. Gard., Vol. 6, 1919 



(137) 



