Family Solanaceae 353 



but the pulp lacks in flavor and taste. Affected 

 plants cease growing, exhibit a thin, spindly growth, 

 and cease producing. The disease is confined to the 

 root system, which is slowly destroyed; it becomes 

 most virulent with the high temperatures. Both 

 Fusarium orthoceras and F. oxysporum also induce 

 a disease on the potato, see p. 327. 



Control. Both Fusaria produce an abundance of 

 chlamydospores in the soil, thus making the eradica- 

 tion of the disease very difficult. Long rotations 

 seem to have no effect in controlling the trouble. 

 Injuring the rootlets at transplanting seems to in- 

 crease the amount of diseased plants. Definite 

 methods of control are as yet lacking. 



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 diseased 

 area becomes chocolate-colored, and the epidermis 

 slightly wrinkled. The rot extends into the interior 

 pulp turning it brown and dry. For further descrip- 

 tion of the causative fungus, see p. 45. 



SOUTHERN BLIGHT (fig. 67 d), see PEPPER, p. 305. 



ROOT KNOT, see NEMATODE, p. 49. 



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