The distribution of vitamin B 1 and nitrogen in the wheat grain

Abstract

The distribution of nutrients within the wheat grain is not uniform. Furthermore, the mode of distribution differs from one nutrient to another. Thus 62% of the total vitamin B$_{1}$ is found in the scutellum which is 1.5% of the weight of the grain and a further 32% in the aleurone layer, which is 7% of the weight. These two regions, however, contain only 20% of the total protein, 72% of which is present in the endosperm. Such a high concentration of vitamin B$_{1}$ as is found in the scutellum has no parallel among the higher plants. It is suggested that a localization of vitamin B$_{1}$ is a normal occurrence in the development of plant tissue, intensified, however, in the case of the scutellum by its relationship to the grain and the plant as a whole. On the other hand, the vitamin B$_{1}$ in the scutellum appears to play no great part in the earliest stages of germination of the seed but is drawn upon in the secondary stages when the seedling is several days old. The principal parts of the wheat grain have been separated by manual dissection of the grain in its natural state, the subsequent assays being carried out by micro-analytical methods.