255 



Antiiracnose 

 Caused by Colletotrichuni cntmpcns Sacc. 

 This disease is reported by Stevens as causing a serious rot of the 

 leaf stalks in many Illinois localities. 



Radish 



The radish is commonly grown by local gardeners for sale at local 

 markets and early in the season is to some extent shipped to more 

 northern markets. It is subject to several diseases, which are, how- 

 ever, rarely severe in Illinois. 



White Rust 

 Caused by Albugo Candida (Pers.) Kze. 



White rust is a fungous disease which results in excessive growth 

 and distortion of the flowers and seed pods. For the most part it is 

 injurious only to plants grown for seed. 



The earliest reported occurrence of it in Illinois was in Champaign 

 county in 1882. It is now known in 17 counties widely distributed over 

 the state, as shown on Map 11 T. The area of most general occurrence 

 appears, however, to lie within the northern third of the state. 



Other Diseases 



Downy mildew, caused by Pcronospora parasitica (Pers.) De Bary, 

 was found in Ogle county in ]92;;2 ; and a leaf spot, caused by Ccrcospora 

 criicifcraritm E. & E., was found in Champaign county by Clinton in 

 ].s;)() but has not been reported from Illinois since then. 



Horseradish 



This crop is commonly grown in home gardens, and local gardeners 

 often grow it in quantity and prepare the roots for sale at their local 

 markets and to manufacturers of condiments. 



Leaf Spot 

 Caused by Ccrcospora aniwraciac Sacc. 



The one disease of horseradish known to occur in Illinois is a leaf 

 spot, round and light-colored. Often the dead s[jots fall out and severe 

 infection may result in considerable leaf injury. 



This disease was first found in Illinois ])y Clinton, who collected 

 leaves infected by it in Champaign county in 189C. It was also found 

 in 1898. 



This leaf spot is now known to occur in 24 Illinois counties, as 

 shown on Map 118. They are widely scattered over the state and indi- 

 cate a state-wide distribution for the disease. 



