Family Chcnopodiaceae 125 



by means of a germ tube which enters the beet leaf 

 again. 2. Uredo Stage. The restdt of infection from 

 the aecediospores is manifested as raised small pus- 

 tules which are thickly scattered over the leaf. 

 When these burst open, uredo or summer spores are 

 liberated. These are round, one celled, and spiny, 

 and the ceU wall is perforated at several places. 

 3. Tdeutospore Stage. As soon as infection of the 

 beet leaves takes place as a result of the penetration 

 of the germinated uredospore infection, other 

 darker pustules are formed. These when rupturing 

 liberate the Tsdnter or teleutospores, which are one 

 ceUed, thick walled, smooth, and darker in color. 

 Their fimction is to carry the fimgus over winter. 

 The infection from the teleutospores the following 

 spring again results in the cluster cup stage. 



Control. It is doubtful if spraying will control the 

 beet rust. The better way is to plow deeply under 

 the affected leaves. This will prevent the germina- 

 tion of the teleutospores in the spring. 



Leaf Spot and Heart Rot 



Caused by Phoma betce Frank. 



This disease is more prevalent as a storage rot, 

 although it also produces a leaf spot in the field. 

 The trouble is as yet of little economic importance. 

 It is not certain whether this rot is the same as that 

 described by Halsted^ as root rot of beet which he 

 attributed to a species of PhyUosticta. 



» Halsted, B. D., New Jersey Agr. Expt. Sta. Bui. 107 : 3-13, 1895. 



