48 



Levi Otto Gratz 



4. Temperature conditions are a greater factor than the total number 

 of diseased plants, in affecting the rate of development of the disease, 

 since frequently, at the ordinary temperatures, it is but a matter of time 

 until a large proportion of the plants are diseased (tables 9 to 15). 



Per cent of 

 damping-off 



80 



00 

 40 

 20 





 100 

 SO 

 00 

 40 

 20 







100 

 80 



00 

 40 

 20 



tZo/o 



3+<7o 



Temperature to -/3 



o e 



Temperature /8 - 19 





Temperature 2.8 -30 



20 40 00 80 100 120 140 100 180 200 220 240 200 280 300 

 Hours after inoculation 



Figure 10. influence of different soil temperatures and soil moistures on 

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

 (table 12, trial ix) 



Soil moistures are given as percentages 



