296 



Journal of Agricultural Research 



as exhibited by ginseng roots. The check plants remained healthy. 

 Plate XXIX, figure 2, is a reproduction of a photograph of two of the 

 inoculated and one check rhizome. Reisolations were made, and the 

 fungus which was obtained resembled the original culture isolated from 

 ginseng. 



Comparison with typ^ specimen. — To determine further the rela- 

 tionship of the Sclerotinia sp. from ginseng to that on Smilacina spp., an 

 examination was made of the type specimen of Sclerotinia smilacina 

 Durand, deposited by Dr. Durand in the herbarium of the botany depart- 

 ment of Cornell University. The specimens showed the black coloration 

 as exhibited by the inoculated rhizomes of Smilacina racemosa as well as 

 the ginseng roots. 



Apothecia on ginseng are rare, and though attempts to produce them 

 were made no success can be reported up to the present time. It is of 

 interest, however, to compare the measurements as given in the original 

 descriptions by Durand (1902, p. 462-463) and Rankin (1912) as shown 

 in the following table: 



Measurements made by the writer from the type material of these 

 species have shown that the asci and ascospores are not to be distinguished 

 either in form or size and agree with the measurements given above. 



CONCLUSIONS 



1. (A) The pathogenicity of Sclerotinia sp. causing the white-rot of 

 ginseng has been established. (B) This species of Sclerotinia is identical 

 with the Sclerotinia libertiana Fuckel occurring on lettuce, celery, and a 

 number af other hosts. 



2. (A) The pathogenicity of Sclerotinia sp. causing the black-rot of 

 ginseng has been established. (B) A consideration of the following facts 

 indicates that Sclerotinia panacis Rankin is identical with Sclerotinia 

 smilacina Durand : (a) Inoculations with a species of Sclerotinia from 

 ginseng on Smilacina racemosa gave positive results, (b) Measurements 

 of asci and spores made by the writer from the type material of both 

 species agree. There is a close agreement in all distinguishing characters, 

 as given in the original description of the two species, (c) The lesions 

 produced by the inoculations are similar on the two hosts and identical 

 with those on diseased plants as they occur naturally. 



