Tomato Diseases 193 



two weeks and should cease about five days before 

 the fruit is picked. If the disease becomes well es- 

 tablished in a house, spraying will prove of little 

 benefit. In that case, the house should be emptied 

 of all vegetation, the soil sterilized with steam or 

 formaldehyde (see pp. 32-43), and wherever possi- 

 ble the house, too, should be fumigated with formal- 

 dehyde and potassium permanganate (see p. 164). 



Black Rot 



Caused by Macrosporium solani E. and M. 



Symptoms. Black rot is a fruit, stem, and foliage 

 trouble. The spots are black, dry, slightly wrinkled, 

 and extend deep into the interior tissue (fig. 37, a 

 and b.). 



The Organism. The mycelium of the fungus at 

 first varies in hue from hyaline to brown, then turns 

 black. The conidiophores and conidia are dark, 

 with three to six transverse and one to two longi- 

 tudinal septse (fig. 37, c). Spraying with Bordeaux 

 mixture is recommended. 



Sleeping Sickness 



Caused by Fusarium lycopersici Sacc. 



Sleeping sickness is a tomato trouble. It is usu- 

 ally brought in with diseased seedlings. 



Symptoms. Infected plants become pale, the 

 leaves wilt and droop and never recover (fig. 38, 

 a.). The droopiness of a diseased plant gives it a 



