5 



BTTLLETIN 934, U. S. DEPARTMENT OE AGRICULTURE. 



Table VI. — Results of parallel inoculation with Rheosporangium aphanidermalus 

 mill Pythium debaryanum on- pine seedlings in autoclaved soil. 



Experiment number, host, and inoculating fungus." 



No. 30, Pinus ponderosa: 



Rheosporangium, strain 229 



Py thium, 2 strains 



Controls 



No. 31, Pinus banksiana: 



Rheosporangium, strain 229 



Pythium, strain 225 



Controls 



No. 5S, Pinus banksiana: 



Rheosporangium, strain 229 



Pythium, 8 strains 



Contr ols 



No. 59, Pinus banksiana: 



Rheosporangium, strain 229 



Pythium, 8 strains 



Controls ; 



No. 61, Pinus banksiana: 



Rheosporangium, strain 351 



Pythium, 2 strains 



Controls 



No. 61, Pinus banksiana and beets in same, pots: 



Beets }Rh eos P ora ngi um > strain 351 



No. 61, beets alone: 



Rheosporangium, strain 351 



No. 62A, beets: 



Rheosporangium^ 229........ .......... 



Pythium, 2 strains 



Controls 



No. 62A, beets: 



Rheo SP orangium{^35?::::::::::::::::::: 



Controls 



No. 62A, beets and Pinus banksiana in same pots: 



Beets I Rh eos P oran gi u rn> strain 229 



Beetsf Rneosporangiuin ' strain 351 



!3 C « 



No. 62B, Jack pine: d 



Rheosporangium^ 229-- ...... ........... 



Pythium, strain 258 



Controls 



No. 66, Jack pine: 



Rheosporangium^ I?;;;;;;;;;;;;;;;;; 



Pythium, 47 strains and substrains 



Controls 



No. 67, Jack pine: 



Rheosporangium!^!?--;;;--;;;;;-;-;-;; 



Pythium, 47 strains and substrains 



Controls 



No. 68, Red pine: 



Rheosporangiumg^ |9-- ::;:; - :; - ; -- :::;: 



Pythium, 47 strains and substrains 



Controls 



Number 

 ol pots. 



2 

 2 

 2 

 3 



5 



5 



235 



25 



5 



5 



235 



23 



5 



5 



235 



18 



Results. 



Emerged 

 (per cent 

 of seed). 



Per pot. 

 23 

 14 

 20 



45 



12 



43 



Per 5-pot 



unit. 



46 



2.6 



50 

 c27 

 c77 



64 

 42 

 46 

 27 



81 

 67 



58 

 53 

 10 

 82 



51 



87 



105 

 124 

 86 

 104 



Damping- 

 off (per 

 cent). 



Per pot. 

 3 



( 6 ) 



20 

 78 

 1 



14 

 22 



33 

 78 

 

 



14 



10 



100 







a Location of the inoculum: In experiment 30, at one point at the edge of each pot; in experiment 31, 

 over the entire pot; in all other experiments, over one-quarter the area of each pot. 



b The breakage of the one seedling not killed while sprouting prevented the determination of results. 



c Double seed density in these pots; emergence and survival figures halved to allow direct comparison 

 with other units. This high seed density may explain in part the higher loss in strain 351 than in strain 229. 



d Experiment 62B was conducted at the same time as 62A, but with a different soil. 



Table VI shows that in experiments 30 and 67 the loss was less in 

 the Rheosporangium pots than in the controls and that in experiment 

 68 the results were entirely negative, while in the remaining seven 



