720 



FUNGI 



The chlamydospores of the covered ' smut ' do not break out 

 from the glumes of the barley ear but remain within the latter until 

 the crop is harvested {B, Fig. 241). They are smoother than those 



A B 



Fig. 242.— I Chlamydospores of Fig. 243. —/I, Chlamydospores of 



naked smut of barley ; II the same covered smut of barley ; B, the .same 



germinating (enlarged about 500 germinating (enlarged about 500 dia- 



diameters). meters). 



of U. nuda and their promycelia give rise to conidia {B, Fig. 243). 

 The fungi appear to infect barley through the flowers chiefly, as 

 in wheat. 



(iv) Eye-' Smut' (U. Secalis Rabenh.) is a rare species. 



Prevention and Remedy for ' Smut ' Fungi. — (a) On small 

 plots it is possible to pluck off and burn all affected ears before the 

 chlamydospores are sufficiently ripe to becarried about by the wind. 



{b) The chlamydospores of the smut-fungi which adhere to the 

 seed-corn and spread the disease may be killed by soaking the 

 grain for five minutes in water at a temperature of 55° C. (131° F.). 

 The grain enclosed in a coarse sack should first be steeped in a 

 tub of water kept at 48° or 50° C. (121 F.) in order to warm 

 it before finally transferring it to the hot water. After remaining 

 for five minutes in the water at 55" C. it must be taken out and 

 plunged into cold water. The grain may then be spread out on 

 a floor to dry before sowing. 



This process if properly carried out does not materially injure 

 the germinating capacity of the grain. It is especially useful 

 and effective for prevention of smut in oats, and is also applicable 

 to wheat, rye, and barley. The embryo of barley is however 



