Tomato Diseases 195 



Rhizoctonia Fruit Rot 



Caused by Corticium vagum B. and C. var. solani 

 Burt. 



This form of rot makes its appearance at the 

 place where the fruit touches the ground. The dis- 

 eased area becomes chocolate-colored, and the epi- 

 dermis slightly wrinkled. The rot extends into the 

 interior pulp, turning it brown and dry. For a 

 further description of the causative fungus, see 

 p. 20. 



Root Knot, see Nematode, p. 28. 



Broom Rape 



Caused by Orobanche ramosa L. 



The parasite fastens itself to the tomato roots 

 whence it derives its food. The parasite produces 

 a base of considerable size below ground from which 

 a cluster of branching stems and bluish-yellow flow- 

 ers appear above ground. The same parasite also 

 attacks the hemp and tobacco out of doors. 



Fumigation Against White Fly 



The tomato is a favorite host for the white fly. 



The different conflicting results obtained by grow- 

 ers in the fumigation treatment may be attributed to 

 the use of widely different varieties of plants. The 

 variations may also be partly due to tightness or 

 looseness in construction of the greenhouse. Inves- 



