INSTITUTE AND COLLEGE, PUSA, FOR 1913-14. 49 



Bulletin No. 34 of the Department while popular descrip- 

 tions have appeared in the Agricultural Journal of 

 India and in a Bengali leaflet. It has been established 

 that the organism responsible for the damage is a form of 

 eelworm (T. angustus) belonging to the genus Tylenchus, of 

 which several species are known to cause serious diseases 

 of cereals. Inoculations with material which, so far as 

 could be determined, contained no other constant organism 

 but the worm, have been successful in producing typical 

 " ufra " in localities where the disease was quite unknown. 

 The disease commences its ravages in July and culminates 

 about September-October when large numbers of motile 

 worms are present. After December they remain immotile 

 and dormant in the dry grains and probably recommence 

 activity only with the flooding of the fields after sowing; 

 in this connection experiments have shown that T . angus- 

 tus can withstand desiccation for even 15 months. It is a 

 curious fact that transplanted paddy appears to be com- 

 paratively immune to natural attack. During the present 

 year efforts have been made to map out the extent of the 

 infected area and an experiment is in progress at Comilla 

 to test remedial measures. It is probable that burning 

 the stubble on the soil after winter harvest will be found 

 to be the most efficient means of combating this disease. 

 The infected area in Eastern Bengal appears to stretch 

 from the Madhupur jungle north of Dacca to the river Ma- 

 hari in Chittagong District. Westward the disease is 

 bounded by the Padma but the eastern limit is uncertain, 

 the infected area almost certainly reaches to the Meghna 

 and further search is needed in the direction of Sylhet. In 

 Tippera the northern limit of infection is near Akhaura 

 on the Assam-Bengal Railway and the disease is parti- 

 cularly virulent in this district at Narjanpur, Comilla and 

 Chandpur, at Begumganj and Chaumuhani in Noakhali 

 District, and also at Fenni in Chittagong District. The 

 most important fact in the distribution of this disease is 

 that it has recently been identified with the " sanhra ' 

 condition of paddy in the Khunti Sub-Division near 



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