DAMPING-OFF IN FOEEST NURSERIES. 



43 



Table III.- 



-Inocnlation experiments with Pythium debaryanum in pots of steri- 

 lized soil — Continued. 





Pyth 



ium strain. 







Results. 











Damp- 





Series, experiment number, 

 and host. 



No. 



Initialstrain 

 from which it 



ber 



of 



pots. 



Inoculation 

 method. 



Emerged 

 (per 5-pot 



ing-off 

 after 

 germi- 



Sur- 

 vival 

 (per 5- 







was reisolated. 





unit). 



nation 



pot 















(per 



unit). 















cent). 





Series B.— Reisolated strains — 

















Continued. 



















338 



No. 295 (in P. 

 ponderosa, 

 expt. 58). 



5 



(a) 



9 



67 



3 





345 



No. 218 (in P. 

 banksiana, 

 expt. 58). 



5 



(a) 



15 



33 



10 





414 



No. 258 (in P. 

 banksiana, 

 expt. 62, 2d 



5 



(a) 



36 



25 



27 



No. 66, Pinus banksiana. . 



















unit). 















415 



do 



5 

 5 



(a) 



59 

 25 



10 



100 



54 





419 



No. 348 (in P. 











banksiana, 

















expt. 62). 















450 



No. 347 (in P. 

 banksiana, 

 expt. 62). 



5 



(a) 



41 



72 



11 



* 



Controls. 

 (338 





25 

 5 



(a) 



75 



7 



14 

 57 



64 





No. 295 (in P. 



3 







ponderosa, 

















expt. 58). 















345 



No. 218 (in P. 

 banksiana, 

 expt. 58). 



5 



(a) 



24 



37 



15 





414 



No. 258 (in P. 

 banksiana, 

 expt. 62, 2d 

 unit). 



5 



(a) 



57 



24 



44 



No. 67, Pinus banksiana. . 



415 



No. 258 (in P. 

 banksiana, 

 expt. 62, 1st 

 unit). 



5 



(a) 



30 



37 



19 





419 



No. 348 (in P. 

 banksiana, 

 expt. 62). 



5 



(a) 



62 



65 



22 





450 



No. 347 (in P. 

 banksiana, 

 ext>t. 62). 



5 



(a) 



53 



27 



39 





(Controls 

 338 





23 

 5 





87 

 85 



5 

 26 



83 





No. 295 (in P. 



(a) 



63 







ponderosa, 

















expt. 58). 















345 



No. 218 (in P. 

 banksiana, 

 expt. 58). 



5 



(a) 



76 



24 



58 





414 



No. 258 (in P. 

 banksiana, 

 expt. 62, 2d 

 unit). 



5 



(a) 



98 



14 



84 



No. 68, Pinus resinosa 



415 



No. 258 (in P. 

 banksiana, 

 expt. 62, 1st 

 unit). 



5 



(a) 



92 



11 



82 





419 



No. 348 (in P. 

 banksiana, 

 expt. 62). 



5 



(a) 



95 



45 



52 





450 



No. 347 (in P. 

 banksiana, 

 expt. 62). 



5 



(a) 



84 



40 



51 





(Controls 





18 





104 







104 











a All inoculations with fragments of agar cultures scattered broadcast at one side of the pot, including 

 about one-fourth of its area. Nothing was added to the controls in experiment 62, but sterile agar was 

 added to the controls in experiments 66, 67, and 68. 



As has been stated, securing positive results did not always mean 

 that the control pots remain uninfected. Even with the most care- 

 ful treatment and the use of boiled water throughout the experiment 



