AND COLLEGE, PUSA, FOR 1915-16 17 



For conducting these' experiments a uniform plot of 

 rice land was chosen at the Sabour Farm. The seed 

 employed was " kalamdan ' which is at present the 

 standard medium aman paddy of the Sabour Farm. It was 

 originally derived from pure culture and its purity was 

 maintained, as far as is possible under field conditions, by 

 rogueing every year. 



In order to do away with the disturbing factors conse- 

 quent on transplanting, it was decided to allow the rice to 

 grow to maturity in the same field where it was sown. 

 After the usual cultivations, the seeds were sown in the 

 third week of May, by dibbling in plough furrows and after- 

 wards covering them up by beaming. Weeding was done 

 when required. The plot had to be irrigated once in 

 August. 



Samples of plants (the exact number of plants varying 

 according to the size) were selected in such a way as to 

 fairly represent the whole crop. It was not possible to take 

 cut the whole root system but care was taken not to lose 

 much of the roots. After the soil adhering to the roots had 

 been washed out the plants were divided into their botanical 

 parts and analysed. The following samples were taken : — - 

 (1) very young seedlings, (2) at the transplantation stage, 

 (3) at preflowering stage, (4) at the flowering stage (two 

 samples, one in which the grain was in the " water " stage, 

 and another in which it was beginning to form " milk "), 

 (5) at the ripe or ordinary harvest stage and (6) when the 

 crop was dead ripe. The results obtained need not be 

 entered here in detail but some of the points observed may 

 be mentioned. 



1. The total dry matter in a rice plant increases up to 

 the time of maturity, the largest increase in the weight of 

 the crop occurring before the formation of the flowers. 



' 2. The percentage of nitrogen generally exhibits a 

 steady and continuous decrease from the first to the last 

 period of growth, the most rapid decline being noted in 

 the second period. The above-ground parts are always 

 richer than the roots in their nitrogen content. At the ear- 



