Studies in Growth and Cellulolytic Enzymes of Tricholoma : With Special Reference to Mycorrhiza Formation

Uppsala

1950

126 S.

34 Abb., zahlr. Lit. Ang.

Bandaufführung

7932

113757

The object of this work has been to compare the physiology of species of the tribe Tricholomeae, especially with regard to their cellulose decomposing ability. 1. The test material comprised pure cultures of 9 different species, representing a total of 17 strains: T. brevipes Bull. ex Fr. [= Melanoleuca brevipes (Fr. ex Bull.)], T. flavobrunneum Fr. ex Pers., T. fumosum Fr. (non Pers.) [= Lyophyllum cinerascens (Bulliard sensu Quélet], T. gambosum F. [= Lyophyllum gambosum (Fr.)], T. imbricatum Fr., T. nudum Bull. ex Fr. [= Rhodopaxillus nudus (Fr. ex Bull.) Maire], T. pessundatum Fr., T. vaccinum Pers. ex Fr., and T. personatum Fr. [= Thodopaxillus saevus (Gill.) Maire]. The latter species has been investigated oly with regard to its ability to decompose litter. (Expt. 19). 2. Fungal growth is expressed either in terms of mycelial dry weight, as total-nitrogen of protein produced or as loss in dry weight of the substrates used. The determination methods are described. 3. The nutrient requirements have been investigated with regard to certain metallic salts. Calcium appears to be particularly growth-stimulative. 4. Ammonium nitrogen and organic nitrogen can be assimilated by all species, nitrate nitrogen by T. nudum only. 5. The optimum temperature for growth in the different species varies between 20° and 30°C. 6. Unter the cultural conditions given, T. nudum grows best at pH 6, while in the case of the other species, the optimum pH for growth is about 5. The established pH optima agree fairly well with the pH values of the natural substrates. 7. All species studied are heterotrophic for pyrimidine or pyrimidine and thiazole. Experiments with additions of sub-optimum quantities of perimental conditions, the inability to synthesize the respective substance(s) is absolute in T. nudum (and T. flavobrunneum), while most of the other species are able to adapt themselves to a certain pyrimidine and thiazole autotrophy.