junei7. i9i8 Effects of Chemicals on Virus of Mosaic Disease 621 



Tabi<E I. — Effects of various chemicals on the infectivity of the virus of the mosaic 

 disease of tobacco — Continued 



PHOSPHORIC ACID — Continued 



Concentration. 



Solution pre- 

 pared. 



Inoculation 

 made. 



1 



Nov. 30,191501 Dec. 18, 1915 (i8 

 days later). 



... .do do 



. . . .do do 



do do 



do do 



do do 



do 1 do 



Plants used. 



Results. 



I gm. to 20 c. c. of virus solution. . . 



I gm. to 50 c. c. of virus solution. . 

 I gm. to 100 c. c. of virus solution. 

 I gm. to 200 c. c. of virus solution, 

 r gm. to 400 c. c. of virus solution. 



Virus without addition 



Tap water only (control) 



10 Maryland 

 Mammoth. 



....do 



....do 



....do 



do 



....do 



do 



All healthy. 



Do. 



4 plants mosaic. 

 9 plants mosaic. 

 8 plants mosaic. 



Do. 

 All healthy. 



CITRIC ACID 



Virus saturated with citric acid 



crystals. 

 I gm. to 50 c. c. of virus solution . . . 

 I gm. to 100 c. c. of virus solution... 

 I gm. to 200 c. c. of virus solution. . . 



Virus without addition 



Tap water only (control) 



I gm. to 10 c. c. of virus solution. 



I gm. to 20 c. c. of virus solution 



1 gm. to so c. c. of virus solution. . . . 

 I gm. to 100 c. c. of virus solution. . . 



Virus without addition 



Tap water and weak solution citric 

 acid (control). 



I gm. to 20 c. c. of virus solution. . 



I gm. to 30 c. c. of virus solution. . 

 I gm. to 100 c. c. of virus solution. 

 I gm. to 200 c. c. of virus solution. 

 I gm. to 400 c. c. of virus solution. 



Virus withovit addition 



Tap water only (control) 



May 23,1914 



.do. 

 .do. 

 .do. 

 .do. 

 .do. 



June 9, 1914 



.do. 

 .do. 

 .do. 

 .do. 

 .do. 



Nov. 30, 1915 



.do. 

 .do. 

 .do. 

 .do. 

 .do. 

 .do. 



May 30,1914 (7 

 days later). 



do 



do 



do 



do 



do 



June 19, 1914 (10 

 days later). 



do 



do 



do 



do 



do 



Dec. 21, 1915 (21 

 days later). 



do 



do 



do 



do 



do 



do 



10 Maryland 

 Mammoth. 



.-..do 



.-..do 



-...do 



....do 



....do 



.do. 



.do. 

 .do. 

 do. 

 .do. 

 .do. 



10 Connecticut 

 Broadleaf. 



....do 



....do 



....do 



....do 



....do 



....do 



All healthy. 



6 plants mosaic. 



4 plants mosaic. 



7 plants mosaic. 



9 plants mosaic. 

 All healthy. 



Do. 



2 plants mosaic. 



5 plants m^osaic. 

 7 plants mosaic. 



10 plants mosaic. 

 All healthy. 



Do. 



Do. 



1 plant mosaic. 



2 plants mosaic. 



3 plants mosaic. 

 8 plants mosaic. 

 All healthy. 



ACETIC ACID 



« Virus filtered clear through filter paper before solutions were made. 

 56114°— 18 2 



