ARS | Publication request: DEVELOPMENT OF PROCEDURES TO IDENTIFY RED CLOVER RESISTANT TO SCLEROTINIA TRIFOLIORUM

Submitted to: Journal of Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 30, 1995
Publication Date: N/A

Interpretive Summary: Sclerotinia crown and stem rot is a destructive disease of red clover. Spores infect the succulent lower leaves in the cool, moist fall conditions. The development of resistant cultivars has been unsuccessful to this point, primarily because of ineffective and unreliable inoculation procedures. In this research, we developed procedures to produce spores of fthe disease organism in the laboratory and procedures for storing the spores until needed. In addition we established repeatable inoculation procedures in the laboratory and controlled environmental chamber to effectively determine the reaction of red clover plants to the organism. These new procedures to produce, store and inoculate with spores will provide an opportunity to select red clover germplasm resistant to Sclerotinia.

Technical Abstract: Sclerotinia crown and stem rot is a destructive disease of red clover. In this study we investigated appropriate procedures for producing and storing ascospores in the laboratory and compared the reaction of selected red clover germplasm when inoculated with either ascospores or mycelium. The two methods produced similar results, although there were exceptions. The eprocedures described to produce, store and inoculate with ascospores will provide an opportunity to select germplasm resistant to Sclerotinia trifoliorum ascospores as inoculum.