THE CONTKOL OF CABBAGE BLACK-LEG. 



11 



Table IV. — Effect of mercuric-cMorid solution upon the black-leg fungus icitMn 

 infected cabbage seeds and upon commercial seeds. 





-i 



.1 

 a 



o 



ft 



© 

 o 



s 



h-1 



Effect upon 

 infected seeds. 



Effect upon commercisl seeds. 





o 

 ■o 



(D 

 CO 



m 



'6 



a 

 o 

 M 



a 

 25 



"3 



If 

 .2ft 



>g 



li 



si 



~ ft 



ft 



One-year-old seed. 



Two- 

 year-old 

 seed. 



Method a of treatment and strength 

 of the solution. 



. Lot 

 3-18.6 



Lot 

 4-19.C 



Lot 

 5-19.(i 



Lot 

 2-18.6 



Lot 

 2-18.6 





■■3 a 



ns 







a 



■a ^ 



M 









If 



ns 







.a 



Qj — - 



"S § 

 a " 



Is 







a 



is 



CG 

 



0^ 



tsg 

 as 



80 









4-18 

 1-19 



4-18 

 4-18 



130 



24 



25 

 25 

 24 

 25 

 25 

 25 

 25 

 10 

 25 

 10 

 25 

 39 

 22 

 24 

 25 

 25 

 28 



13 



25 

 25 



75.3 

 66.6 



56.0 

 20.0 

 16.6 

 12.0 

 12.0 

 20.0 

 36.0 

 20.0 

 12.0 

 50.0 

 12.0 

 12.8 

 6.3.6 







4.0 





 28.5 



15.3 

 

 8.0 



22.3 

 



4.0 







4.1 









 12.0 



8.0 







4.0 

 20.0 



4.0 



2.5 



1.0 



















'6" 



8.0 



95-100 







96 







92 







92 



n 



J)0 







Method 1: 



10 

 20 



99 

 97 

 99 

 99 

 99 

 99 

 98 





 

 





































Strength 1 to 1,000 \ 



30 4-18 

 40 4-18 











92 



























60 



10 



20 



/20 



30 



/30 



40 



60 



60 



120 



120 



180 



180 



30 

 60 

 60 

 120 



10 

 20 

 30 

 60 

 120 



10 

 20 

 30 

 60 

 120 



4-18 

 4-18 

 4-18 

 1-19 

 4-lS 

 1-19 

 4-18 

 4-18 

 1-19 

 4-18 

 1-19 

 4-18 

 1-19 



4-18 

 4-18 

 1-19 





























































1 











98 







93 







94 







88 







85 



■0 





98 

 93 



i 





















98 







90 







81 



e 



82 













85 



e 



77 



e 



63 



e 



71 



e 















84 



e 



70 



e 



57 



H- 



63 













Method 2: 



f 



87 

 64 



i 



1 







72 

 74 



i 

















C5 



(=» 















1 















53 



e 







Method 3: 























81 

 78 

 74 

 42 

 13 



































 

 + 



Strength 1 to 500 < 



1-19 



24 



20.8 



8.3 































































+'+ 



Method 4: 















94 

 95 

 95 

 83 

 51 





 

 

 

 e 







































Strength 1 to 500 \ 





























1-19 



</50 



62.0 



2.0 































































a Method l=not soaked previous to treatment, rinsed after treatment; method 2i=not soaked previous 

 to treatment, not rinsed after treatment; method 3= soaked in water previous to treatment, rinsed 

 after treatment; method 4= dipped in 70 per cent alcohol previous to treatment, rinsed after treatment. 



6 Wisconsin Hollander variety grown at Racine Wis., in 1918. 



c AU Seasons variety grown at La Conner, Wash., 1919. 



d Jersey Wakefield variety grown at La Conner, Wash., 1919. 



« Symbols used: 0= No injury; ©=sUght; H-=medium; +=severe; -|--|-= very severe. 



/ Disinfected by seed grower. 



g Dipped in 95 per cent instead of 70 per cent alcohol. 



With the second method of treatment (soaking in the disinfectant 

 without rinsing in water), seedling injury occurred after a shorter 

 period, evidently as a result of the prolonged action of the disinfectant. 

 No advantage of this over the first method was found, however, 

 since the action upon the fungus was no more rapid than upon the 

 host. 



