Cereal Chem 51:84 - 95.  |  VIEW ARTICLE
Protein and Amino Acid Content of Rice as Affected by Application of Nitrogen Fertilizer.

R. M. Patrick, F. H. Hoskins, E. Wilson, and F. J. Peterson. Copyright 1974 by the American Association of Cereal Chemists, Inc. 

Nitrogen fertilizer (N) applied to three major Louisiana rice varieties at specified stages in the physiological development of the rice plant produced a marked response in crude protein content. More protein was usually found in the grain when all the N was applied at seeding, or where half of the N was applied at seeding and half applied late in the season at the 2-mm. panicle stage. Protein content was increased by both the 80- and 120-lb. rates of N with the 80-lb. rate providing the greatest increase. The addition of fertilizer N produced large increases in yield for all varieties. There was a striking inverse relationship between grain yield and protein content between the 1968 and 1969 crops. In 1968, grain yield was higher and protein content lower than in 1969. The yield of protein was relatively constant for both years. Although some variation in amino acid content was evident, there was no marked effect of variety, rate and time of N application, or method of seeding on amino acid composition of the protein, even though there were considerable differences in protein content. Contents of lysine and threonine, first- and second-limiting amino acids in rice, were markedly reduced in the milling process.