56 REPORT OF THE AGRICULTURAL RESEARCH 



1,100,000 tons of clean rice. Both the main winter crop, 

 or " aman," paddy and the autumn, or " aus," crop suffer, 

 but the damage is much greater in the former, as its long 

 growth period allows of a progressive increase of the 

 parasite. The most severely attacked varieties are those 

 grown in the lower lands, subject to early inundation and 

 where transplantation is not possible. A large part of the 

 rice grown is of this class ; the transplanted varieties, 

 grown on higher land, occupy a smaller area and do not 

 seem to get the disease. The lower land is under water 

 for a considerable period every year and gets little cultiva- 

 tion, being often allowed to remain covered with weeds and 

 stubble after harvest until the first spring showers. The 

 organism, an eelworm of the genus Tylenchus, mentioned 

 in last year's report as the suspected cause of the disease, 

 has been found during the year to be constantly present in 

 every case and attempts to induce the disease experiment- 

 ally by inoculating healthy paddy with it have been fully 

 successful both at Pusa and at Dacca. The worm is one 

 previously undescribed and, up to the present, has been 

 found only on paddy suffering from ufra, or in the stubble 

 from the diseased crop. On the living plant it is active, 

 feeding and reproducing freely; after the death of the 

 plant it assumes a passive condition, lying coiled up within 

 the sheaths and glumes, and in this state can remain alive, 

 if kept dry, for many months. Activity is resumed, at 

 Pusa, about April. The length of the life cycle is not 

 yet known, but there are several generations during the 

 growth period of the crop and the rate of multiplication 

 appears to be very considerable. 



Experiments have been undertaken, in collaboration 

 with the Bengal Department of Agriculture, to devise 

 methods of fighting this disease. Paddy probably suffers 

 less than any other cereal from epidemic diseases and every 

 effort will have to be made to check the spread of ufra. 

 The losses caused by it are very great; in some cases the 

 crop is not worth harvesting, in many others it is reduced 

 to half or a quarter of the normal. In the districts referred 



