__ o 



The life history of the fungus is not yet known. It has been 

 observed that in the case of a single plant bearing three heads, only 

 seven grains in the youngest head were affected, whilst all tlie grains 

 in the other two heads were healthy. This supports a statement 

 made by Butler to the effect that possibly it may be due to a localized 

 infection of a single flower. 



It is a custom of the felaheen of the provinces of Minya and Asyut 

 to eat the fungus when young, and it is said to have a peculiar sweet 

 taste. The eating of the fungus, although a perfectly sound method 

 of controlling the disease, cannot be recommended or condemned 

 here .because the effect of large quantities of this fungus on the health 

 of the consumer is not known. The only recommendations that can 

 be given for treatment of the disease are : 



(1) Obtain seed from a healthy crop. 



(2) Remove and burn the spore-sacs when young. 



(3) Where possible, do not grow millet for a few years on soil 

 where the disease has occurred. 



The Head Smut (Ustilago reiliana Kuekn.). 



The disease caused by the Head Smut is of rare occurrence in 

 Egypt and the loss caused by it is negligible It is also known in 

 India, Southern Europe, U.S.A., and Asia. 



Usually the millet ear is converted into a large spore-sac (sorus) 

 which measures 7'5 to 10 centimetres long by 3'75 to 5-5 centimetres 

 broad (Plate II, Fig. 1). The grey membrane of the sorus usually 

 ruptures before emerging from the sheathing leaves, exposing a 

 network of dark brown almost black fibrous filaments, surrounded 

 and intermingled by a powder of the same colour. The fibrous 

 filaments are the fibro- vascular bundles of the millet and the powder 

 is composed of the spores of the fungus (Plate II, Fig. 2). "ki- 

 termingled with groups of sterile, hyaline cells. The hyaline cells 

 measure 7 to 15 \i in diameter. The spores are dark brown, round, 

 covered with small spines and measure usually 13 u in diameter. 

 The size of the spores is very uniform. They germinate readily in a 

 one per cent solution of cane sugar and produce a .short, thick, 

 four-celled promycelium, bearing sporidia at the apex and near the 

 septa (Plate II. Fig. 3). The sporidia bud off other sporidia readily 

 and remain joined end to end to form chains. The spores retain 

 their power of germination for as long a period as eight years. 



Infection of the flowers does not take place in the case of this 

 disease. The method of infection is usually from spores which arg> 

 present in the soil. These attack the young millet seedling so that 

 the whole plant becomes infected, resulting in (lie production of a 



