Scanning electron microscopy : a potential for selecting high lysine sorghum with agronomically acceptable kernel characteristics

Abstract

Sorghum (Sorghum bicolor (L) Meonch) is the fourth leading cereal produced in the World where it serves as the staple food for millions of people. Like most cerals, sorghum is deficient in many of the essential amino acids and therefore lacks good nutritional quality protein. However, with the discovery of high lysine sorghums, renewed interest has caused the initiation of new research by various groups in attempts to improve the protein quality and agronomic quality of many different sorghum lines. The objectiveness of this research were to; compare the structure of four high lysine mutants (SC1030-5-4, Dented; IS11167, Dented; IS11758, Dented and P-721, Plump) to normal sorghum (SC1030-5-4 normal and SC0170), and evaluate the potential of using scanning electron microscopy (SEM) as a practical tool for selecting individual kernels with a reduced size and number of protein bodies that would inturn be high in lysine content. Microscopic examination of the three dented high lysine mutants revealed they were essentially devoid of protein bodies. The protein content of the high lysine grain was higher than normal grain and the lysine content was double that of normal sorghum. P-721 had a 60% improvement in lysine and contained larger and more protein bodies than the dented grain. However, the size and number of protein bodies was much less than normal grain.