In investigations on the grass regeneration biology a special attention was paid to the formation of aerial tillers and branching pseudostolons in <i>Dactylis glomerata</i> L., <i>Festuca arundinacea</i> Schreb., <i>Festuca pratensis</i> Huds., <i>Festuca rubra</i> L., <i>Phleum pratense</i> L., <i>Lolium multiflorum</i> Lam., <i>Lolium perenne</i> L., <i>Phalaris arundinacea</i> L., <i>Arrhenatherum elatius</i> (L.) P. B., <i>Holcus lanatus</i> L., <i>Agropyron repens</i> (L.) P. B., <i>Avenastrum pubescens</i> (Huds) Opiz and <i>Agrostis alba</i> L. Aerial tillers, vegetative short ones and with partly elongated internodes as well as generative tillers formed in tufted and rhizomatous grasses. Parental raised tillers, on which aerial tillers developed, had the anatomical structure specific for grass stems. In tufted grasses, moreover, parental branching pseudostolons developed; in their cross section the arrangement of tissues specific for stolons was observed. They constituted the starting point for agglomerations of new plants rooting in soil, contrary to raised tillers. In some grass species, beside pendant roots, shorter roots grew at the base of aerial tillers; they surrounded with a ring the parent shoot in the node, thus reinforcing the connection of aerial tillers with the stem. An attention was paid to the favourable role of branching pseudostolons in the sward thickness formation. Conditions of the arrangement of tissues in the stem cross section, owing to which the rhizomatous form is developed, are discussed. The fertilization with compost or the covering with sand results in the formation of tillers resembling pseudorhizomes.
Introgression Mapping of Genes for Winter Hardiness and Frost Tolerance Transferred from Festuca arundinacea into Lolium multiflorum
