FUNGI IMPERFECTI 



321 



study of the disease does not 

 appear to have been reported. 

 The carnation stem wilt, 1,2 

 or rosette, is occasionally 

 important both in the 

 greenhouse and garden. As 

 in the case of the cotton 

 wilt and other similar dis- 

 eases, the fungus seems to 

 gain entrance through the 

 root system, and its path 

 of attack is mainly the 

 tracheal tissues. Steriliza- 

 tion of the soil seems to 

 be the only effective means 

 of prevention. 



Fig. 153. Fusarium on Carnation: 



Rosette Effect 



(Photograph by Geo. F. Atkinson) 



XXV. ROOT ROT OF THE VINE 

 Dematophora necatrix Hartig 



Hartig, R. Rhizomorpha (Dematophora) necatrix n. sp. Unters. a. dem 

 forstbot. Institut zu Miinchen. 3 : 94-141. pis. 6, 7. 1883. 



Viala, P. Monographie du Pourridie" des Vignes et des arbres fruitiers. 118 

 pp. 1 pis. 1892. 



Viala, P. Pourridie". Maladies de la Vigne. 248-329. figs, j 4-1 25. 1893. 



There is said to exist throughout a large part of Europe and 

 the United States a root disease of the grapevine due to the fun- 

 gus given above. In recent years investigations in the United 

 States have apparently failed to develop any special disease to 

 which the characteristics usually associated with Dematophora 

 would apply. Moreover, the studies in Europe, unfortunately, 

 develop much conflicting evidence. It would, therefore, seem 

 necessary before forming any final judgment in this matter to 

 await further critical study. It is quite possible that several inde- 

 pendent diseases are here confused. The fungus is generally de- 

 scribed as having several types of mycelium. It is stated that 



1 Atkinson, Geo. F. Carnation Diseases. Amer. Florist 8 : 720-728. 1893. 



2 Sturgis, W. C. Preliminary Investigations on a Disease of Carnation. Conn. 

 (New Haven) Agl. Exp. Sta. Rept. 21 : 175-181. 1897. 



