234 HELMINTHOSPORIUM SPP. ON CEREALS AND SUGARCANE IN INDIA 
ETIOLOGY OF THE DISEASE. 
The parasitic nature of the fungus was proved by the following inoculation 
experiments. 
TABLE IX; 
Inoculations on the leaves of jowar with Helminthosporium ‘isolated from the 
diseased leaves of jowar. 
) } E 
No. of | 
No. Date inocula- | . ie q Control ee REMARKS 
tions | imfecte infecte 
i te1=319 24 19 9 | 
2 | 24-11-19 9 9 1 | 
3 30-1-20 6 6 1 
4 21-5-20 19 11 1 | oe 
| | | 
5 10-6-20 18 14 eee - Reisolated from No. 4 and 
| | inoculated. 
6 7-320 10" |. 320 | 1% 
7 | 11-12-20 1c oe 8. | TP ae Plants kept in a moist 
| warm room. 
— | | 
Total 97 Ta | ey De 79%, 
When jowar Helminthosporium is inoculated on jowar the spots formed 
ave typical and resemble those found in nature. The fungus was reisolated 
from an inoculated spot, taken into culture and again inoculated and the 
same symptoms and results were obtained. This proves the parasitic nature 
of the fungus. 
MoRPHOLOGY OF THE PARASITE. 
The mycelium of this fungus is found in the matrix of the infected portion 
of the leaf. It is present also in the vessels of xylem. Very often they form 
stromatic masses in the epidermal cells. 
Conidia are formed on both sides of the spot and conidiophores arise singly 
or in cluster of three or more emerging from stomata (Plate III, figs. 12-16). 
Conidia are 57 to 136 by 19 to 26m in diameter (Plate III, figs. 7-11). Jowar 
Helminthosporium resembles more the Helminthospermmm on maize. from 
Burma, Almora and Dharwar than that from Pusa and Malda. The spores 
of yowar Helminthosporium are straight, spindle-shaped and resemble those op 
maize from Burma, Almora and Dharwar, but spores from Pusa specimens are 
