Wire Stem of Cabbage 51 



and the remainder were kept as controls; but as soon as the first lot had 

 succumbed with such rapidity, the others were likewise placed at that 

 temperature with similar results. This experiment was later duplicated 

 by growing one hundred and eighty plants (twelve culture vessels) at a tem- 

 perature of 12° C. for three weeks, and another equal number of seedlings 



Per cent of 

 damping-off 



100 



son 



60 



40 H 



20 







ioo H 



80 



60-| 



40 



20 ^ 







5/Q/o 



o g 6 % 



Temperature £^--Zb° 



No dam pi no off 



at 



Temperature 32 -34? 



— i 1 1 1 1 1 1 1 1 1 1 1 1 1 — 



20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 

 Hours after inoculation 



Figure 13. influence of different soil temperatures and soil moistures on 

 rate of damping-off of cabbage seedlings caused by corticium vagum 



(TABLE 15, TRIAL XIl) 



Soil moistures are given as percentages 



at 30° C. for the same length of time, and finally placing them in the same 

 tank at 20° C. They were immediately inoculated by placing the inoculum 

 in direct contact with the seedling. The rate as well as the total per- 

 centage of damping-off was practically the same in both sets of seedlings. 

 Tin' moistures were the same in all the culture vessels. 



One of the interesting observations in the experiments is that of 

 the definite lag in the rate of damping-off in those trials (VI, XI, and XII, 

 tables 9, 14, and 15) which were performed in April, when the air tempera- 



