278 Diseases of Greenhouse Crops 



The Bermuda Disease 

 Cause, cultural and mites, 



Symptoms, The trouble is characterized by a 

 spotting and distortion of the leaves, flowers, and 

 scales of the bulbs, as well as by a general stunting 

 in growth. In severe cases, there appear yellowish 

 white, longitudinal, sunken spots, and streaks on the 

 first leaves as they show above ground. As growth 

 proceeds each succeeding whorl becomes similarly 

 affected, and finally collapses and dries. Even the 

 flowers become spotted, shrunken, and distorted. 

 Occasionally plants appear healthy, until the disease 

 suddenly breaks out on the flowers. It is seldom 

 that all the leaves in the same whorl are uniformly 

 affected (fig. 58, b and c). The diseased foliage 

 or whorls may be irregularly scattered along the 

 main stalk. The greatest damage occurs when the 

 flowers are spotted, since the plants become un- 

 salable whether the leaves are healthy or not. 



Cause. There are many current theories as to the 

 cause of the disease. Some growers believe that it is 

 due to soil exhaustion. Others believe that it is due 

 to the removal of the flower stalks by the growers in 

 Bermuda, who desire to sell them, thus giving them 

 a double source of profit. It is claimed that this 

 practice weakens the bulbs by depriving them of 

 their proper nourishment. Still others are of the 

 opinion that the bulbs become weakened by being 

 harvested prematurely. Finally some growers hold 

 that the trouble is due to an insect which feeds on 



