Characterization of the Leaf Epidermis of Barley (Hordeum vulgareL. 'Himalaya')

Abstract

The cell types of mature leaves of barley ( Hordeum vulgare L. ‘Himalaya’) are described. Blade and sheath epidermal cell types were characterized according to their position relative to the veins, stomatal rows, and sclerenchyma cells. Cells over veins were further classified according to the size of vein. Cell lengths of the approx. 15 different cell types ranged from approximately 50 μm to over 2 mm. The principal difference in cell length between the abaxial and adaxial surfaces was seen for cells lying between the veins; on the adaxial surface these cells (bulliform cells) were about 200 μm long whereas those on the abaxial surface were over 2 mm in length. Total file number across the blade width was the same on the abaxial and adaxial surfaces. However, there were more cells lying over veins than between veins on the adaxial surface, and vice versa for the abaxial surface. The detailed description of leaf epidermal cell types of barley in this study provides the basis for comparison with mutants which differ in leaf length (Wenzel et al ., Annals of Botany79 : 45–50, 1997).