The Grain Structure of Sorghum Related to Water Uptake and Germination

Abstract

A wide range of variability was found in pericarp structure of a range of sorghum varieties. Endosperm type varied from chalky to solid corneous with a complete range of intermediate types. Brown grains were found to contain only a small amount of corneous endosperm. The relation of this character to bird and weevil resistance is discussed. The rate of water uptake is related to grain size, endosperm type and mesocarp thickness, being fastest in small, chalky grains with a thick mesocarp. The relationship with degree of courteousness was slight but very highly significant. Rate of germination depended to some extent on rate of water uptake. Slower germinating grains are to be preferred in tropical conditions. Sorghum grains survived soaking and drying very well so long as they had not germinated. However, grains with endosperm became very fragile after soaking and drying.