MARASMIUS SACCHARI; A PARASITE ON SUGAR CANE

Abstract

1. The fungus is a vigorous saprophyte, which can be found in abundance on fragments of cane and cane leaves in and on the surface of the soil. Also on the old dead leaves of growing canes. 2. The mycelium frequently cements the leaves and checks the growth of the canes, but its presence does not necessarily indicate that it is the cause of the retarded growth or the death of the cane. 3. The fungus is a parasite and penetrates roots, leaves and stalks of young canes very readily. 4. It kills a small percentage of young canes and sometimes injures older canes. These losses depend on soil and climatic conditions and vary with the seasons. They are probably less than some reports indicate and greater than is indicated by others. 5. The fungus sometimes attacks seed cuttings and kills the buds. The writer has one record of a killing of 20 percent. 6. The writer has not observed the pea-like bodies which Howard described as sclerotia but has observed the large sclerotia formed by Rhizoctocnia grisea which was described several years earlier as Sclerotium griseum Stevenson. 7. The writer has demonstrated that the fungus will grow from old material or from a pure culture and penetrate the living tissues of canes growing in glass cylinders or in sterilized soil in pots. 8. The fungus penetrates the canes, leaves and roots and will kill many of them when the conditions are favorable. 9. A considerable amount of the fungus either in or outside the cane appears to be necessary for the production of sporophores. 10. Sporophores were produced in my cultures, on cane grown in cylinders, in from two to four months after inoculation.