Comparative leaf anatomy of the genus Hordeum L. (Poaceae)

Abstract

The genus Hordeum L., one of the most economically important cereal crops in the tribe Triticeae, has a worldwide distribution mainly in temperate and dry regions of the world. In Turkey, Hordeum is represented by 12 taxa, namely Hordeum violaceum Boiss. & Hohen., H. geniculatum All., H. marinum var. marinum, H. marinum Hudson var. pubescent (Guss.) Nevski, H. murinum L. subsp. murinum, H. murinum subsp. glaucum (Steudel) Tzvelev, H. murinum subsp. leporinum (Link) Arc. var. leporinum, H. murinum subsp. leporinum var. simulans Bowden, H. bulbosum L., H. spontaneum K.Koch, H. distichon L., and H. vulgare L. The main objective of this study is to assess the significance of anatomical characteristics of the leaves. For this purpose, dehydrated specimens were embedded into paraffin and transverse sections were gathered. Furthermore, the leaf surfaces were examined. Results of the study show that anatomical characteristics of the leaf blades vary between the taxa in both qualitative and quantitative values. Sclerenchymatic cells, silica bodies, and stomata, furrow and rib properties, the existence of midrib and bulliform cells, and indumentum properties such as arrangement, density, and length of macro hairs are all included in these diagnostic characteristics. Based on these anatomical characteristics, an identification key for the taxa is given for the first time. © TÜBITAK.