The Botrytis Blight of Tulips 331 



Botrytis Tulipae (Libert) comb. nov. 



Sclerotium Tulipae Lib. Crypt. Ard., no. 36. 1830. 



Sclerotium Tulipae Weinn. Hym. Ross., p. 647. 1836. 



Sclerotium entogenum West. Herb, crypt. Belg., no. 827. 1841-1859. 



Botrytis parasitica Cav. Appunti die Pathologia Vegetale. 1st. Bot. R. Univ. Pavia. 



Atti 2:1:432. 1888. 

 Sclerotinia parasitica Massee. A text book of plant diseases, p. 383. 1899. 



Botrytis Tulipae (Libert) comb. nov. may be briefly described as follows : 



Mycelium variable in diameter, often anastomosing, branches not 

 constricted at the base; conidiophores arising directly from the mycelium, 

 erect, brown in color, proliferating, twisting on their axils when dry, 

 slightly swollen at the base; branches of conidiophore arising at an angle 

 of about 60 degrees, dichotomous, not streptiform, apices swollen; conidia 

 large, 12-24 x 10-20 fx, obovate, reddish brown in mass; microscopically 

 gray to hyaline, smooth with a short stalk, often or commonly not remaining 

 attached; sclerotia at first white, finally black, small, 1-2 millimeters in 

 diameter, circular or somewhat elliptical in outline, flattened vertically 

 and often convex. Microconidia globose, about 3 /jl in diameter, occurring 

 on special penicillate, obclavate conidiophores arising in white tufts from 

 the substratum (fig. 40). Parasitic on Tulipa spp. 



Cavara (1888:432) says that Sclerotium entogenum West, develops on 

 the stalks of asparagus and does not differ greatly from Scl. Tulipae 

 Lib.; he says, moreover, that Westendorp thinks Sclerotium entogenum 

 West, should be regarded as the type of the species. Sclerotium Tuliparum 

 Klebahn is a species which must not be confused with Botrytis Tulipae. 

 It is a large, sclerotial form with which no conidial stage has yet been 

 connected. 



The species must, therefore, still be classified among the Hyphomycetes 

 of the Fungi Imperfecti. It is placed there by Lindau (1900:435) in the 

 subgroup Mucedinaceae-Hyalosporae-Botrytideae. 



Klebahn (1904:21)-, from his studies on B. Tulipae, seems certain of 

 the connection of the sclerotia occurring on the tulip bulbs with the 

 conidial form on the leaves. However, as he did not use pure-culture 

 methods, it seemed desirable to clear up this point. Pure cultures were 

 made by the writer from the sclerotia occurring on the bulb and from 

 conidia on the leaves of the same tulip plant. These cultures were identical, 

 and when inoculated into sterilized tulip leaves both produced normal 

 conidia and sclerotia. Both also caused infection of healthy tulip plants. 



