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plant gradually turning from green to red, then yellow, 

 then brown, and finally withering. The discoloration 

 begins at the tip, and is accompanied by a drooping 

 of the plant. The fruits are none or are very poor, and 

 ripen prematurely. The disease appears to be due to 

 a mycelium which infests the roots and rots them. It 

 is said to be readily transmitted from the parent to the 

 new plants. Kecent studies indicate that it may be 

 due entirely to the use of certain fertilizers. 



The disease may be held in check by using nothing 

 but healthy stock. In case of an outbreak, pull and 

 burn the diseased plants, and treat the soil from which 

 the plants were pulled with lime. Fertilize the plants 

 well, and thus enable them to resist the disease. 



The Spike or Long Leaf. This disease is well known 

 in Porto Rico and Florida. At first the leaves are long 

 and slender, but as the disease progresses they assume 

 the form of rod-like bundles. In severe cases the 

 central leaves do not unfold. Usually no fruit is 

 produced, but whenever formed it is small and worthless. 

 The disease originates through the use of too much 

 acid phosphate. When plants are once affected the 

 disease character is readily transmitted through the 

 slips. The grower should always select healthy plants 

 for setting. Use dried blood, bone meal, or other organic 

 fertilizer. If necessary to use acid phosphate the grower 

 should also use 300 or 400 pounds of lime per acre 

 shortly afterwards. 



Leaf Spot. This has been reported as troublesome 

 in Porto Rico, and may be introduced into other places 

 at any time. It first appears as small brownish spots 

 J to J inch in diameter. They increase in size, become 

 oval, lose colour in centre, but maintain a brown border. 

 They are frequently on the edge of the leaf. Although 

 this leaf disease is not considered serious, a number of 

 the leaves die. It can be controlled by good cultivation 

 and drainage. 



Tangle Foot. This disease is common in Florida 

 and the West Indies. The leaves turn yellow, beginning 



