Carnation Diseases 233 



consequently profuse topping, which opens the way 

 to the disease. 



Control. Peltier* recommends the use of medium 

 sized sturdy plants in preference to large, bushy 

 ones. As much as possible, overcrowding should 

 be avoided. During the first three months after the 

 plants have been brought in, the temperature should 

 be kept as low as the plant will tolerate. The 

 syringing should never be given in the evening nor 

 in the cloudy weather. It should be given on clear 

 days in the morning so that the plants will be dry 

 by the evening. In topping a plant, care should be 

 taken to make clean cuts and to avoid leaving stubs. 

 In gathering flowers, break them off at a node. 

 Finally all diseased material should be pulled out 

 and destroyed by fire. 



Root Rot 



Caused by Rhizoctonia solani Kuhn. 



Symptoms. The disease is at first manifested by 

 a yellowing of the affected plant or branch. A few 

 days later actual wilting takes place. This is true 

 only in sunny weather. During cloudy weather, 

 the plant remains turgescent even though the stem 

 may be badly rotted. The trouble is confined to 

 the stem end or to the roots of the plants. Deep 

 brown lesions usually precede the rot and indicate 

 the places where infection started. High tempera- 

 tures and deep planting favor the disease. Of the 



♦Peltier, G. L., The Amer, Flor. 56: 725-726, 1916. 



