Leaf vasculature in barley, Hordeum vulgare (Poaceae)

• Published in: American journal of botany 1990-05, Vol.77 (5), p.636-652
• Main Authors: Dannenhoffer, J.M. (University of Wisconsin, Madison, WI), Ebert, W. Jr, Evert, R.F
• Format: Article
• Language: English
• Subjects: ANATOMIA DE LA PLANTA; ANATOMIE VEGETALE; Anatomy; Barley; Biological and medical sciences; Botany; Cardiovascular system; Corn; FAISCEAU VASCULAIRE; FEUILLE; FLOEMA; Fundamental and applied biological sciences. Psychology; Grain; HACES VASCULARES; HOJAS; HORDEUM VULGARE; LEAVES; Mesophyll cells; Morphology, anatomy, histology, cytology; PHLOEM; PHLOEME; PLANT ANATOMY; Plant cytology, morphology, systematics, chorology and evolution; PLANT VASCULAR SYSTEM; Sclerenchyma; SIEVE PLATES; Sieve tubes; SISTEMA VASCULAR DE LA PLANTA; Spermatophyta; Sugar; Sugar cane; Sugarcane; SYSTEME VASCULAIRE DES PLANTES; TEJIDO (ANATOMIA); TISSU; TISSUES; tracheary elements; ULTRAESTRUCTURA; ULTRASTRUCTURE; VASCULAR BUNDLES
• ISSN: 0002-9122; 1537-2197
• DOI: 10.1002/j.1537-2197.1990.tb14449.x

The vascular system of the Hordeum vulgare L. leaf consists of multiple longitudinal strands interconnected by transverse bundles. In any transverse section, the longitudinal strands can be categorized into three bundle types: small, intermediate, and large. Individual longitudinal strands intergrade structurally from one bundle type into another as they descend the leaf. At their distal ends, they have the anatomy of a small bundle. As they descend the leaf, most intergrade into intermediate bundle and then into large bundle types. All strands with large bundle anatomy extend basipetally into the stem. Typically, the other longitudinal strands, which do not intergrade structurally into large bundles, do not enter the sheath, but fuse with other longitudinal strands above the junction of the blade with the sheath. Despite the decrease in number of longitudinal bundles entering the sheath, an increase takes place in the total cross-sectional area of sieve tubes and tracheary elements. A linear relationship exists between leaf width and total bundle number in the blade but not in the sheath. Moreover, a linear relationship exists between cross-sectional area of vascular bundles and both total and mean cross-sectional area of tracheary elements and thin-walled sieve tubes.