Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 3, 1997
Publication Date: N/A
Interpretive Summary: Fungi in the family Sclerotiniaceae cause serious diseases of vegetable crops in the field as well as during post-harvest storage. These diseases include watery soft rot of potatoes, white mould of corn, and lettuce drop and result in millions of dollars of damage to these crops. The beneficial fungus Sporidesmium sclerotivorum attacks this destructive group of plant pathgoens and could be used as a biological control agent. However, knowledge of the host-range of this fungus is needed in order to determine its effectivenes on diverse fungal pathogens. This research resulted in an increased knowledge of the sclerotial-forming fungal against which this potential biocontrol agent will be effecitve. This knowledge will be used by scientists who are working to develop and apply this fungus as a means of on-chemical control of disease-causing fungi. Effective use of the mycoparasite will reduce crop loss due to these plant pathogens and decrease the use of chemicals needed to produce and market fresh vegetables.
Technical Abstract: Sporidesmium sclerotivorum is a fastidious mycoparasite of sclerotia. Sclerotia of fungi in the Sclerotiniaceae, including species of Sclerotinia, Botrytis and Monilinia, stimulated germination of macroconidia of Sporidesmium sclerotivorum. Sclerotia-forming fungi that were outside of this family were unable to do this. The presence of sporigermin, the germination stimulant for Sp. sclerotivorum macroconidia, or a related compound appears to be characteristic of sclerotia produced by fungi in the Sclerotiniaceae. Sporidesmium sclerotivorum readily colonized sclerotia of Sclerotinia spp. and one species of Botrytis both in soil and in vitro, but was unable to successfully attack sclerotia of any fungus outside of this family. Botrytis bifurcata supported prolific growth as a host of Sp. sclerotivorum, which proved to be a destructive mycoparasite of the sclerotia. Originally discovered on Sclerotinia minor and known to control llettuce drop, Sp. sclerotivorum may be useful for biocontrol of plant diseases caused by other members of the Sclerotiniaceae.