Tomato Diseases 183 



advanced stage, the primary and secondary veins 

 also become browned. Affected stems are peppered 

 with minute brown lesions, irregularly scattered, and 

 apparently superficially seated. In advanced stages, 

 however, the lesions seem to work deeply into the 

 vascular bundles. On the fruit the disease appears 

 as surface lesions which are variously shaped. The 

 surface of the spot may be unbroken and smooth, 

 or rough and scabby. In advanced stages, the super- 

 ficial lesions work in deeply in the flesh of the fruit. 

 Upon maturing, the affected areas fail to take on 

 the normal color. Such fruit is spotted and scabby, 

 and is worthless for market purposes. Up to the 

 present, the exact cause of the disease and methods of 

 control are unknown. It seems that the trouble is 

 not caused by a pathogenic organism, but rather by 

 some unknown chemical or physical derangement of 

 the soil. 



Blossom End Rot 

 Cause unknown. 



Blossom end rot, also known as point end rot, 

 may be found wherever tomatoes are grown. It is 

 a disease of the fruit only. In some seasons fifty 

 per cent or more of the fruit crop is ruined by it. 

 It seems to be serious in dry weather and on light 

 soils. 



Symptoms, Infection is manifested as a water- 

 soaked spot at the blossom end of the fruit (fig. 

 36, a.). The size of the spot may be that of a pin- 

 head, or it may spread so rapidly as to involve half 



