3 



smutted oar. Sometimes only the lower portion of the ear 1 

 infected and the upper portion may grow out to form leafy shoots. 

 This fungus also causes the Head Smut of maixc. 



Special treatment is unnecessary ! his disease at pro,- 



but it is advisable to out and burn diseased cars, at the same time 

 preventing the sporefl being shed on the ground. Ill the event of a se 1 . 

 local attack taking place millet should not be grown on that soil 

 for five years. By that time probably most, of the spores will have 

 germinated and perished. 



The Grain Smut (Sphaceolotheca sorgki, Lk., Clinton). 



The (irain Smut occurs more often than the Head Smut and less 

 often than the Long Smut. The loss caused by the disease is negli- 

 gible at present. It is known in most parts of the world where millet 

 is grown, and is said to cause great losses sometimes in dilTerent 

 parts of India. 



As in Long Smut the individual grains are attacked. The number 

 of diseased grains exceeds that in Long Si i o-isos whc: 



grain in a head is infeoted yre not infrequent. It has also been 

 served that some grains may be attacked by Long or Head Smut and 

 some with drain Smut. The attacked grain is replaced by a grey, 

 oval, spore-sac (sorus). measuring 4 to 1:2 millimetres long by -2 to 

 3 millimetres broad. The glumes remain unaltered and can be seen 

 surrounding the bases of the sori (Plate 111. Figs. I and -2). The wall 

 of the sorus becomes ruptured fairly easily. The sac is filled with 

 a dark brown mass of spores and a central, rigid, slender, column 

 of tissue (Plate III, Fig. 3). The latter is composed of the tissue of 

 the millet and is traversed by libro-vascular bundles. The sp 

 when seen in mass are dark brown, but when placed in water tln>\ soon 

 separate into individual spores, and on examining under a microscope 

 they will be seen to be light brown in colour, slightly oval or round, 

 smooth, and measure 5 to 7 11, in diameter (Plate 111, Fig. 1). 



Spores from specimens of the disease collected this year germi- 

 nated readily in water. They can, however, retain their germinating 

 powers for as long a, period as six years or more. Spores pheed in 

 water vary considerably in their method of germination. Some 

 produce a four-celled promycelium the cells of which give rise to 

 spindle-shaped sporidia (Plate III, Fig. o). The latter rarely bud on" 

 secondary sporidia. Other spores, instead of forming sporidia, give 

 rise to germ tubes laterally and apically from the cells of the promy- 

 cehnni. Again some spores do not produce a definite promycelium, 

 but instead septate branching germ tubes are formed. 



Infection takes place in the same manner as in the closed Smut 

 of barley. Spores adhere to the seed coats, and when sown together 



