Studies on sclerotium-forming fungi: I. Sclerotium cepivorum Berk and S. tuliparum Klebahn Part 1. Cultural studies

Abstract

1. Brief accounts of the literature dealing with the fungi Sclerotium cepivorum Berk, and Sclerotium tuliparum Klebahn are given. 2. Morphology of the two fungi has been described. The only spores produced by S. cepivorum are microconidia on certain media only. Attempts to germinate these microconidia almost uniformly failed as only 14 spores altogether germinated on 20 per cent, tulip juice. 3. A comparative cultural study of S. cepivorum and S. tuliparum showed that while both grew well on a great variety of media, nevertheless there was in the case of each a certain amount of specific reaction to the juice of its own host plant. In particular, crude onion juice is markedly inhibitory to the growth of S. tuliparum. Boiling of the juice largely removes this effect. S. cepivorum does not grow well in tulip juice, boiled or unboiled. 4. Sclerotium cepivorum is favoured by an acid reaction of the culture medium while Sclerotium tuliparum by a neutral or slightly alkaline reaction. 5. The temperature range of growth for both fungi is approximately l°-35° C., with an optimum near 20° C. 6. There is no significant difference by light factor either in growth rate or in the general appearance of the cultures of the two fungi.