The carotene and protein in oats and barley at different stages of growth

The amounts of nitrogen and β-carotene have been determined in oat and barley plants at different stages of growth and with and without a late top dressing of nitrogenous fertilizer. The nitrogen decreases steadily until the kernels begin to fill; it is markedly increased throughout by the extra dressing. The β-carotene, which accounts for about 80% of the ‘crude’ carotene in the oven-dried material, continues to fall until it reaches very low values when the crop is ripe. There is a very close correlation between total nitrogen and carotene in the plant.