Leaf anatomic characterization of populations of Bromus auleticus Trin. Ex Nees (Poaceae)

Abstract

This work was carried out to characterize the leaf anatomy of eight Bromus auleticus populations collected in Rio Grande do Sul, Brazil, and called A5, A6, A8, A17, A23, A26 and A27. Totally expanded leaves were collected from plants in the vegetative stage and were sectioned and stained with basic fuchsine and alcian blue. A single layer of epidermis with a smooth and fine cuticle on both surfaces, short tricomes, vascular bundles in three sizes, and the presence of cells with lignified walls along the bundles and on the leaf edge were observed in all populations. The number of bulliform cells varied from three to five, with the exception of population A25, which ranged from five to eight cells. Three populations presented long tricomes (A6, A23 and A27) and palisade chlorenchyma (A6, A7 and A26), five had grooves on the leaf surface (A8, A17, A23, A26, A27) and homogeneous chlorenchyma (A5, A8, A17, A23, A27), two presented a large intercellular space in the mesofile (A7 and A17), and two showed a more visible cuticle on the abaxial surface (A7 and A8). These variations could reflect differences in relation to the nutritive value of the populations and be used in plant breeding programs for the genetic improvement of bromegrass.

Keywords

• bromegrass
• forage plant
• plant anatomy