CORN SMUT 



395 



The Smut of Oats, Stinking Smut of Wheat, and Covered Smut 

 of Barley are very similar in habit and require similar treatment. 

 Sometimes, as m case of the Stinking Smut of Wheat, the infec- 

 tion of the seedling may be due to spores lodged in the soil as 

 well as to spores adhering to the kernel. 



Loose Smuts of Wheat and Barley. — The Loose Smuts of 

 Wheat and Barley mature and shed their chlamydospores when 

 the grain is in flower. These 

 spores are borne away by the 

 wind and when falhng on the 

 flowers of their respective 

 hosts, grow hyphae into the 

 young kernel. The kernel 

 continues its development, 

 but when mature it has con- 

 cealed within a tiny Smut 

 plant, which is able, when the 

 kernel is planted, to resume 

 its growth and develop in the 

 grain plant. Much of the 

 damage from these Smuts 

 can be avoided by seed selec- 

 tion. Treatments for these 

 Smuts must aim at killing 

 the tiny Smut plants con- 

 cealed in the seed grain. 

 Soaking the seed in cold 

 water five hours and then in 

 water 129° F. for ten minutes 

 is recommended. 



Corn Smut. — Corn Smut 

 is the most conspicuous of 

 the Smut group. It attacks 



all tender regions of the Corn plant but does most damage to the 

 flowers which become much enlarged and transformed into Smut 

 balls. Tumor-like developments of the Fungus occur also on the 

 leaves and stem as well as on the ear and tassel. In Figure 352 

 is shown an ear in which the kernels are replaced by the tumor- 

 like masses of the Fungus. These Smut bodies have a thin, 

 grayish, hyphal covering, and within the chlamydospores are pro- 



FiG. 352. — Ear of Com with kernels 

 destroyed and replaced by masses of 

 Smut. From Farmers' Bulletin 507, U. S. 

 Dept. of Agriculture. 



