1922.] Potato Leaf Curl Demonstrations. 



1021 



Wye, South Eastern Agricultural College. 



Diseased Yield. 

 Curled. Healthy. (Healthy =100.)- 



Weight ... 3 cwt. 2 qr. 8 lb. 7 cwt. 2 qr. 26 lb. 46' X 



No. of plants 645 645 



Cambridge, School of Agriculture. 



Failure through drought. 

 Manchester, Victoria University. 

 Trials postponed. 



At the following Institutes the results are estimated at yield per acre : — 

 Bangor, University College of North "Wales. 



Diseased Yield. 

 Curled. Healthy. (Healthy =100. > 



Weight ... 6 T. 16 cwt. 2 qr. 9 lb. 14 T. 8 cwt. 3 qr. 21 lb. 47-3 



On May 20 healthy plants well above ground, curled plants only just 

 showing ; this difference in rate of growth was apparent throughout the- 

 growing season. Only two or three tubers failed to produce plants. 



Newport, Salop, Harper- Adams Agricultural College. 



Diseased Yield. 



Curled. Healthy. (Healthy =100.) 



Weight ... 6 T. 10 cwt. 3 qr. 8 lb. 8 T. 12 cwt. 2 qr. 18 lb. 75*7* 



Leeds University, Garforth Farm. 



Diseased Yield. 



Curled. Healthy. (Healthy =100.) 



Weight ... 6 T. 13 cwt. 1 qr. 11 T. 1 cwt. 1 qr. 60'2 



Very few misses. 



Sutton Bonnington, Midland Agricultural College. 



Diseased Yield. 



Curled. Healthy. (Healthy '=100 .) 



Weight ... 2 T. 10 cwt. 1 qr. 3 lb. 5 T. 4 cwt. 2 qr. 16 lb. 484 



Newcastle, Armstrong- Colleg-e, Cockle Park Farm. 



Diseased Yield. 



Curled. Healthy. (Healthy=100.) 



Weight ... 4 T. 11 cwt. 10 T. 14 cwt. 42'1 



It will be seen from the results that seed which was infected 

 with Leaf Curl yielded, with the exception of two cases, only 

 , about one -half that given by the healthy seed, and this, it may be 

 repeated, was from seed derived from plants which were only 

 mildly attacked the previous season. The full figures with regard 

 to the proportions of ware, seed and chats in each crop are not 

 published in full on account of space, but are available for those 

 who are interested in the subject. 



It is clear from the facts given that the planting of good seed 

 is one of the most vital factors in successful potato growing. In 

 these lean times no grower should be careless as to this matter, 

 and no one can afford to take risks and secure only half 

 a crop. 



* When the figures for Harper- Adams College are compared with other 

 centres, especially Bangor and Leeds, it would appear that the healthy seed at 

 this centre must have suffered in some way and not produced its normal crop. 



