MOSAIC DISEASE OF TOBACCO. 



91 



The lime was applied to this new soil, in the different amounts indicated, 

 one week previous to the setting of the plants. 



No appreciable differences were observable in the subsequent growth as 

 regards intensity of mosaic symptoms, all the plants being comparatively 

 evenly mosaicked. There was not a single case of recovery. 



Table III. — Effect of Liming on Mosaic. 



[Infected seed bed soil, lime, seed.] 



The lime was here applied to a soil which was heavily infected, and the 

 seed sowed very thinly in the flats containing the various amounts of lime 

 and soil. The seedlings were allowed to grow in the flats until they were 

 counted. They were naturally crowded somewhat, but were free from 

 insects during the period of growth. It is possible that some infection 

 may have occurred, however, but there are very strong indications that 

 liming had no beneficial action in lessening the disease. As the results 

 are so variable the matter cannot be considered as absolutely settled, but 

 certainly no consistently favorable results were obtained in this experi- 

 ment from the use of lime. 



Effect of Colored Light on Mosaic Disease. 



In connection with work on the mosaic disease of tobacco it had long 

 been noted, in that section of the Connecticut Valley where the crop was 

 grown under shade, that the plants appeared in general to be much less 

 affected with the mosaic disease than were those grown in the open. 

 This fact has already been noted by Sturgis ^ in Connecticut. Investi- 

 gations were outUned, in conjunction with other work on this disease 

 already under way, relative to a study of the effects of various light 

 conditions on the intensification or reduction of the disease. While the 

 writer's preliminary work was in progress, Lodewijks ^ published a paper 



» Sturgis, W. C: On the Effects, on Tobacco, of Shading and the Application of Lime. Conn. 

 Agr. Exp. Sta. Ann. Rept., 23, 252-261 (1899). 



* Lodewijks, J. A., Jr.: Zur Mosaikkrankheit des Tabaks. Rec. Trav. Neerlandais, Vol. 7, 

 107-129 (1910). 



