Small Grains 



145 



both grains and glumes and at harvest time only the naked 

 stern of the plant remains, the spores having been scattered 

 about the field. Figure 53 shows this condition very plainly. 

 The spores mature when the grain is in blossom. They are 

 scattered about the 

 field and if they 

 lodge on a blossom- 

 ing head of wheat 

 they germinate and 

 penetrate to the 

 inside of the grain. 

 Stinking smut de- 

 stroys only the 

 kernel, the glumes 

 still remaining 

 around the .spores. 

 The outside of 

 smutted grain is 

 intact, but the in- 

 side, instead of a 

 wheat grain, is a 

 mass of spores. The 

 smut balls often 

 found in threshed 

 grain are masses of 

 stinking smut, not 

 loose smut. The 

 smut balls are shown 

 in Fig. 54. When the grain is threshed, the spores are scat- 

 tered. They adhere to the outside of the grain of wheat, es- 

 pecially in the crease or among the tuft of hairs at the upper 

 end. 



The fact that the spores of loose smut are on the inside of 

 the grain and those of stinking smut are on the outside makes 

 the treatment for the two diseases different. It has been found 



FIG. 54. Stinking smut of wheat. Comparison of 

 sound head and sound kernels with smutted head 

 and smut balls. 



