THE SYSTEMATIC POSITION OF THE FUNGUS CAUS- 

 ING ROOT-DISEASE OF SUGAR-CANE IN NATAL 

 AND ZULULAND. 



By Paul A. van der Bijl, M.A., D.Sc, F.L.S. 



Read July ii, 19 19. 



Ever since 1917 we have given attention to the root-disease 

 of sugar-cane, and in a pamphlet published in 1918* we men- 

 tioned that two Basidiomycetous fungi occur on and around the 

 roots and basal leaves of cane in our plantations, namely, a 

 fungus which shows sphaero-crystals of calcium oxalate in its 

 mycelium, and which we referred to the Phalloids, and the second 

 one, which we then provisionally referred to M arasmius sacchari. 

 Neither of these two have to date been observed to fruit naturally 

 in our plantations. The latter fungus was isolated, grown in 

 the laboratory, and this short paper deals with it only, and now 

 places it systematically. 



Though grown on a number of different media, and under 

 the most varied conditions, every attempt made in the laboratory 

 to induce it to fruit gave only negative results. 



In the pamphlet above cited we make mention of certain 

 inoculation experiments, and in these experiments, following the 

 method which gave success with M arasmius sacchari in the hands 

 of Howard in the West Indies, we attempted to induce it to fruit 

 under conditions more natural than would obtain in a laboratory, 

 but were once again not successful. 



Marasmius sacchari fruited comparatively easily in the 

 experiments recorded by Howard, and our continued non-success 

 led us to doubt whether the fungus in South Africa is the true 

 Marasmius sacchari of other cane countries. We decided that 

 it was not, and that our fungus belonged to the genus Himantia, 

 a genus of Basidiomycetous fungi the fructifications of which are 

 unknown. Our fungus showed peculiar stellate crystals of cal- 

 cium oxalate borne on short, swollen (at their apices'), lateral 

 outgrowths of the hyphge. Reviewing the literature of cane-root 

 fungi, we found these crystals had been previously observed, but 

 until towards the end of 1917 it was not quite clear whether or 

 not the fungus bearing them was Marasmius sacchari. 



Lewton Brain (1905) appears to have been the first to draw 

 attention to the presence of these crystals in a cane-root fungus, 

 and he, too, mentions it as remarkable that at that time no toad- 

 stools had been observed in Hawaii. Later Cobb (1909) men- 

 tions the existence of two species of Marasmius {sacchari and 

 Hazvaiiensis) in Hawaiian cane-fields, and he refers to the 



" Root Disease in Cane and Suggestions for its Control." Bull. No. 

 4 of 1918, Dept. Agriculture, Union of South Africa. 



