Family Solanaceae 341 



ammonium compounds. This is especially true on 

 sandy loams. On the other hand, nitrate of soda or 

 lime seems to check blossom end rot. 



SUNBURN 



Tomato fruits are often burned while they are on 

 the vines by strong sunlight beating on the exposed 

 fruit. This results in a scalding of certain parts (fig. 

 67 e), loss of color, and a local drying which produces 

 white spots with a dry peppery appearance. Such 

 fruit is unfit for the market. Sunburn may also 

 result from other and indirect causes. In dry sea- 

 sons the tomato cannot supply the necessary supply 

 of moisture to the foliage and fruit. As a result, they 

 become weakened and contain numerous starved 

 areas which dry up when exposed to strong sunlight. 

 The same result may also be brought about by the in- 

 direct action of the numerous leaf and root diseases. 



Control. In sections where sunburn is prevalent, 

 it is advisable to plant tomato varieties with dense 

 foliage. The plants should be put out as early as 

 possible so that the vines may attain their maximum 

 before hot weather sets in. The soil should be prop- 

 erly fertilized, and sufficient humus incorporated to 

 hold the moisture during periods of high temperatures. 

 Irrigation should be practiced wherever possible. 



MOSAIC 



Cause Unknown. 



A lengthy discussion on mosaic has already been 

 given on p. 83. Mosaic on tomato is a common field 



