The Structure of Normal and High-Lysine Barley Grains

The structure of the starchy endosperm of normal and high-lysine barleys has been examined by light and scanning electron microscopy. The small granules (1-5 μm) seen using the latter method have been demonstrated to be small starch granules rather than protein bodies. Certain of the high-lysine mutations (Risø 1508, Notch-2, lys 449 and lys 95) cause dramatic shrinkage of the endosperm structure whilst others (Risø 7 and 56) cause little change. In particular Risø 1508 causes a decrease in small starch grains whereas those grains present in Notch-2 are all much smaller than normal. The endosperm of lys 449 shows considerable disruption of the cells.