99^ " Stripe " Disease of Tomatoes. 



[JAN., 



"STRIPE" DISEASE OF TOMATOES.* 



S. G. Paine, 



Lecturer in the Department of Plant Physiology and Pathology, 

 Imperial College, London, 



AND 



W. F. Bewley, 



Mycologist, Experimental and Research Station, Cheshunt, Herts. 

 The disease known as " Stripe is of common occurrence in 

 nurseries in this country, and at times it causes the grower 

 considerable losses. During the early part of 191 9 about 

 25 per cent, of the crop obtained from the experimental houses 

 at the Cheshunt Station was so badly affected that it could be 

 sold only as " seconds." " Stripe " disease has been known to 

 cause complete loss of the crop in badly-infected houses. In 

 1910 some examples of plants attacked by this disease were 

 received at Kew from two localities where it was stated to be 

 present in epidemic form. Though stripe is mainly a disease 

 of the forcing house, it has been observed in a garden where 

 plants were grown in a position facing south and sheltered by 

 a high wall. A similar disease, which is believed to be identical 

 with stripe, has been reported from the United States and 

 Canada, and was once found in the neighbourhood of Toronto 

 on field tomatoes, of which about i per cent, were affected. 



Description, — ^The symptom^s of the disease are well marked ; 

 the main features are brown stripes on the stems, brown, sunken 

 patches on the fruit, and brow^n, shrivelled areas on the leaves. 

 The stem stripes or " blazes " may occur at intervals along the 

 stem or, in bad cases, may be so numerous that no region of the 

 stem is free from them ; they vary from small, brown spots to 

 long, sunken furrows, which often extend from the base of one 

 leaf to the node below. The fruit " spots " are irregular sunken 

 blotches of a light or dark brown colour scattered promis- 

 cuously over the surface of the fruit. The affected leaves at 

 first show light yellow patches between the veins, which ^ turn 

 brown later and spread so that large areas are reduced to a dry, 

 shrivelled condition, causing considerable distortion of the 

 leaves. 



The disease frequently occurs in the seed-bed, producing 

 rapid destruction of the plants, and necessitating fresh sowings. 

 Most commonly the disease does not show itself until the tops 



* This account of the disease is an abbreviation of an article shortly to 

 appear in the Annals of Applied Biology, Vol. VI., in which the disease and 

 its causal organism are to be fully described. 



