20 



It was stated in the previous publication (Agr. Expt. Stat. 

 Formosa, Report No. 10, 1915) that the entire plant contained the 

 highest percentage of nitrogen four or five weeks after transplantation. 

 Similarly, in the present axperiments the percentage of protein is 

 found to be highest at the young stage, and to decline rather rapidly 

 when the plant begins vigorously to increase its amount of dry matter. 

 Then, towards the end of maturation, the decrease In percentage is 

 more gradual. Hence it is clear that the rice plant needs a relat- 

 ively large quantity of protein substance to produce new culms in 

 the period of tillering. Consequently, much nitrogenous manure should 

 be supplied early in the plant's life. 



The absolute quantity of protein in the entire plant gradually 

 increases during the plant's development. The increase of protein, 

 is not proportionate to the total increase of dry matter, for there is 

 a production of substances other than protein, which yield a larger 

 contribution to the increase of dry matter. At a young stage the 

 increase of protein proceeds more rapidly than that of the other dry 

 matter ; but in the period of vegetative growth the case is reversed. 



The parts of the rice plant have a decreasing persentage of 

 protein at successive stages of growth. the leaves are always found 

 to have the highest percentage until the time of flowering, but a 

 remarkable reduction in percentage takes place during maturation, 

 owing to the translocation of protein to the stems, as will be des- 

 cribed later. The decrease of percentage throughout the plant's life 

 is greater in the leaves than in the stems. And the decrease of 

 percentage in the roots is very slow after the sudden diminution 

 which occurs at the young stage of growth, (the roots have a rather 

 higher percentage of protein in the period of tillering, new young 

 roots being produced). The decrease in percentage of protein in 

 the stems and leaves before the time of flowering, is dependent on 

 the active production of dry matter other than protein in these 

 organs, yet the reduction which appears during maturation is chiefly 



