History and Host Range

Although the importance of Sclerotinia as a plant pathogen has long been known but detailed historical account of Sclerotinia was given by Purdy (1979). In 1837, Liebert described Peziza sclerotiorum. Fuckel (1870) erected and described the genus Sclerotinia. He chose to honour Liebert (1837) by renaming Peziza sclerotiorum with a newly coined binomial, Sclerotinia libertiana. According to Wakefield (1924), Fuckel apparently disliked the combination of S. sclerotiorum and elected to establish the new one. S. libertiana Fuckel was in use until Wakefield (1924) showed it to be inconsistent with the International Rules of Botanical Nomenclature and cited G. E. Massee as the proper authority for Sclerotinia sclerotiorum (Lib.) Massee because he has used that binomial up to 1895, but de Bary used it in his 1884 contribution. Thus, the proper name and authority for this pathogen seems to be Sclerotinia sclerotiorum (Lib.) de Bary. Eriksson (1880) described the pathogen of clover stem rot as Sclerotinia trifoliorum Erikss. Then Wolf and Cromwell (1919) suggested that clover stem rot may have present near Berberbeck in Hesse, Germany in 1857. It was also mentioned that the disease name may be synonymous with the name clover sickness, a disease known in England in the early 1800s and on which personnel at Rothamsted Experiment Station began work in 1849. However, the disease apparently was attributed to S. trifoliorum in 1897. According to Wolf and Cromwell (1919), the first report of S. trifoliorum in the USA was published in Delaware in 1890. Jagger (1913) described the small sclerotial type from lettuce, celery and other crops in several locations in New York and from lettuce in Sanford, Florida as S. minor. Valleau et al. (1933) suggested that S. minor and S. trifoliorum are identical with S. minor occurring on host (lettuce) not commonly recognized as a host for S. trifoliorum, thus, associated host and size of sclerotia were used as the basis for speciation of Sclerotinia isolates. Additional species were named as S. intermedia Ramsy, S. serica Keay, S. trifoliorum Erikss. var.fabae Keay and S. sativa Drayton and Groves. Dennis (1956) included S. sclerotiorum, S. trifoliorum (also the variety fabae), S. minor, S. serica, and S. tuberosa but did not mention S. intermedia or S. sativa, it suggests that these latter two as valid species were not recognized or that these species occur only in the new world. It appears that others share concepts or parts of concepts with Dennis, because S. intermedia, S. saliva, and S. serica, along with S. trifoliorum var. fabae seem to have disappeared from the literature as if they were the “Putdown men” of Sclerotinia spp.