542 BOARD OF AGRICULTURE, 



the fmij^i which you cannot examine without the assistaiice of 

 powerful microscopes, the sporule being so minute as to be 

 unrecog'nizable by the naked eye. 



The first one to which I invite your attention is the fungus 

 termed by Ilenslow, Bunt, which affects wheat. " When examined 

 under the microscope this fungus is seen to consist of vast 

 numbers of extremely minute globules of a dark color, and which 

 arc at first attached to a mass of matted thread-like matter. A 

 single grain of wheat would contain more than four million such 

 ispores, but it is hardly possible to conjecture how many sporules 

 each spnre contains, since they appear, under the microscope, to 

 be a faint cloud of vapor whilst they are escaping from the 

 ruptured spores. Although this fungus confines its attack to the 

 young seed, it Kooms to be a condition essential to its propa- 

 gation, that it should be introduced into the plant during the early 

 stages of its growth, and that its sporules are most readily 

 absorbed by the root during the germination of the seed from 

 which the plant has sprung. It has been clearly proved that 

 wlioat plants may be easily infected and the disease thus propa- 

 gated, by simply rubbing the seeds before they are sown, with the 

 spores, or black powder, of the fungus. It is also as clearly 

 ascertained that if seeds thus tainted be thoroughly cleansed the 

 plants raised from them will not be infected. The grains contain- 

 ing traces of fungus spores have a little oily or greasy matter, 

 which causes the spores to adhere with much tenacity to the 

 the surface. Lime removes this oily substance and cleanses the 

 grain. The odor of grain infected by Bunt is very disagreeable, 

 and this serves to distinguish it from Smut, which is a kindred 

 fungus. The smut-fungus destroys the ear by first occasioning 

 tlie innorinost parts of the flower to become abortive, Avhile the 

 little stalks on which these are seated, swell and become very fleshy. 

 The fungus then consumes the whole of this fleshy mass, and at 

 length appears between the chaff scales in the form of a black soot 

 like powder. This disease not unfrequently attacks wheat, and it 

 is common in barley, and also in oata. In this country there has 

 been much inaccnracy in the use of the word Smut as applied to 

 grains. It has b(?on most generally used Avith reference to the 

 fungus disease of wheat. The fungus called Bunt is termed Urcdo 

 Caries by botanists, and Smut is Uredo Segetnm. Another Uredo, 

 having the specific name Kubigo, is known as Bust. " Tliis Uredo 

 forms yellow and brown oval spots and blotches upon the stem 



