OBSERVATIONS ON THE DOWNY MILDEW 



(SCLEROSPORA GRAMINICOLA (SACC.) 



SCHROET.) OF BAJRI AND JOWAR. 



BY 



G. S. KULKARNI, L .Ag., 

 Mycological Assistant, Bombay Department of Agriculture. 

 This disease is found on three cereals, bajri (Pennisetum tijphoi. 

 deum), jowar (Andropogon Sorghum), rala (Setaria italica), and a 

 fodder grass (Euchlcena luxurians). It was first described in India 

 by Dr. Butler 1 . He has dealt with it in detail, giving a full descrip- 

 tion of the fungus and the changes it induces in the hosts. My 

 observations are chiefly concerned with the field characters of the 

 disease on bajri and jowar, though certain additional interesting facts 

 have been observed in connection with the conidial form on jowar. 



Bajri Sclerospora. -i 



The disease is detected on bajri plants in their very young stage, 



just after they put forth two or three leaves. The affected plants 



are pale yellow in colour, and the under surface of the leaves is covered 



with a white downy material, consisting of sporangiophores and 



sporangia. These are found on the upper surface of the leaves also 



to some extent. Ultimately, when the plant is mature, the peculiar 



malformed head is produced. For the detailed description of the 



inflorescence and the further effects of the fungus on the host, the 



Memoir already cited should be consulted. My observations are :— 



(1) That infection seems to occur only at or before the seedling 



stage of the plant, for the disease is confined to plants 



which show it from the beginning and the secondary 



• Butler, E. J. Some diseases of Cereals caused by Sclerospora graminicola. Mem.' Dept, 

 of Agric. in India, Bot. Ser., II, No. 1, 1907, 



