Symptoms 



bright brown, then whitish spots (also on stem), 

 with dark fungus tufts arranged in concentric 

 circles. In bad cases most of leaf involved. 

 Black-mould or fairy-ring disease due to 

 Heterosporium echinulatum. Treatment as for 

 rust. Select resistant varieties. 



Spots yellowish, later with a rose or dull 

 violet margin; brownish-black dots upon the 

 spot. Leaf - spot due to Septoria Dianthi. 

 Treatment as for rust. 



Grey or white powdery covering over fohage. 

 Mildew. Oidium sp. Sprinkle with flowers of 

 sulphur, and maintain a dry atmosphere while 

 giving sufficient water in soU. 



Flower. — Masses of violet-brown dust re- 

 placing pollen, so that centre of flower is 

 smutty. Ustilago violacea. Smut. Plant is in- 

 fected while very yotmg and is perennially 

 aflEeoted. Destroy (4). 

 Cattltflowbr. See Cabbage. 

 Cbleeiao. See Celery. 

 Celery. 



Foliage. — Dark dull green to brown or 

 yellowish-brown spots on foliage, densely covered 

 with black dots. Leaf-spot due to Septoria 

 Petroselini var. Apii. Destroy affected parts 

 by flre (3, 4) ; spray from May onwards with 

 Bordeaux mixture (7) ; use seed free from 

 infection (sterilise by hydrogen peroxide (6)). 

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