120 



PRITECTION OF PLANTS — 1923-24 



Paine and Bewley (5) on the contrary found organisms ir the roots and 

 consider that infection is possible from the root up into the plant. 



Distribution of Stripe in Greenhouse. 



From a study of the South House, (Fig. 3), it is clearly seen that the outer 

 rows in each bed where the disease occur are much more heavily infested 

 than the inner rows. In a conversation with Mr William A. Ross, Entomologist- 

 in-charge at the Vineland Station, Ontario, he remarked that he had observed a 

 similar distribution of the disease in greenhouses near London, Ontario. In the 

 North House where there were onh' a few diseased plants when the count was 

 taken, these occured on the outside rows only; the two rows on the inside in 

 every case being entirely free from the disease. A count of the south house 

 shows that of 213 diseased plants, 135 were on outside rows and 78 on inside. 

 J^^J^ From the foregoing it might be inferred that the disease is probably trans- 

 mitted b}^ the greenhouse attendant both when watering the plants, disbud- 

 ding or pollinating them. Incidentally, it might be mentioned that the to- 

 mato crop in the two houses shown above was a complete failure. 



SOUTH House 



Fig. 3.- 



-Plan of green houses showing distribution of stripe disease of 

 tomatoes. First plants at X on March 12. Count 

 taken- April 5, 1923. 



