26 NUTRITION OF FUNGI 



Both fractions were found essential for the growth of Nemato- 

 spora gossypii, but /-inositol was not necessary for the growth of 

 Melanospora destruens. Hawker further found that inositol pro- 

 duced a sporulation response with Sordaria fmiicola, Rosellinia 

 necatrix, and Zygorhynchns vwelleri. 



Schopfer (1936) demonstrated that Thy corny ces blakesleeamis 

 will not erow in a nutrient solution containing mineral salts, as- 

 paracrine, and dextrose unless thiamin is added. Kogl and Fries 

 (1937) secured favorable growth responses from the addition 

 of thiamin to cultures of P. blakesleeamis, Phytophthora cactoruvu 

 Nectria coccinea, Sclerotinia cinerea, Poly poms adustus, P. abie- 

 tinus, and Fovies pinicola, but no benefit to the growth of Lenzites 

 saepiaria Mas apparent. Biotin and inositol were each beneficial 

 to the growth of Neviatospora gossypii and Lophoderinium 



pinastri. 



Robbins and Kavanaugh (1938) observed that the following 

 species show increased growth in the presence of thiamin: Phy- 

 tophthora capsici, P. cinnamorm, P. cryptogea, P. drechsleri, P. 

 palm'rcora, P. parasitica, P. boehmeriae, P. cactorwn, P. cambivora, 

 Phycoviyces nitens, Pythium arrhenovianes, P. poly clad on, 

 Sphaerulina trifolii, Schizophylhnn commune, Sclerothnn del- 

 phinii, and 5. rolfsii. Schopfer (1938) showed the need for thia- 

 min by several Mucorales, including Absidia ramosa, Chaetocla- 

 * dhnn brefeldii, Choanephora cucurbit arum, Dicranophora fulva, 

 Mucor ramannianus, Parasitella simplex, Phycoviyces blakesle- 

 eamis, and Pilaira anovmla. Quantz (1943) found that 1 y of 

 thiamin per 100 ml of solution was optimum for Allomyces 

 kniepii and Blastocladiella variabilis. 



Thiamin increased the production of dry matter by Colly bia 

 velutipes 400% [Marczvnski (1943)] and was definitely benefi- 

 cial to Stereum frustulosmn [Noecker and Reed (1943)]. Both 

 riboflavin and pvridoxine, however, were ineffective with these 

 two wood-destroving species; when biotin in amounts of 5 y 

 per 26 ml of medium was supplied, definitely increased growth 

 was noted with S. frnstulosum. 



Attention has also been directed in the studies of growth factors 

 to methods of assav of thiamin, biotin, pantothenic acid, inositol, 

 and other substances. These methods depend upon the need 

 for an external source of accessory substance by a particular 



