Resumen

SALAS R, J. E.; MOGOLLON M, N. J.  y  SANABRIA, M. E.. Anatomy of the vegetative structure and origin of stolons, microtubers and adventitious roots of in vitro potato (Solanum tuberosum L.) plants cv Granola. Rev. Fac. Agron. [online]. 2003, vol.20, n.2, pp.131-143. ISSN 0378-7818.

Potato plants (S. tuberosum L.) cv. Granola, produced under in vitro conditions were sampled during the phases of growth, development and induction of tuber development in order to describe the anatomy of vegetative structures and the origin of stolons, micro-tubers and adventitious roots. This last activity was studied from initiation up to the formation of micro-tubers. Samples were fixed in 90% F.A.A. following conventional techniques for anatomical studies. Both permanents and semi-permanent slides of transverse and longitudinal sections of the tissues being studied were prepared. Decolorized portions of apical, intermediate and basal parts of the foliar lamina were also processed for studying some of the epidermal characteristics. The vascular bundles of aerial stems were arranged in collateral axis and separated by zones of parenchymatous tissues from which the interfacial cambium, xylem, phloem and adventitious roots were originated, while stolons emerged up from the axillar zone of the same stem. The micro-tubers were formed in the sub-apical portions of the stolons and in the axillary area of the aerial stem. In such structures, the phellogen was originated from sub-epidermal cellular layers. Both epidermis turned out to be uni-stratified, with trichoms being simple, uni-cellular, pluri-cellular and some cases glandular. Paracytic and anomositic stoma were also observed on both surfaces. Finally the adventitious roots were found to be diarchic. Marked anatomical differences arose when comparing our results with those of other researches where others cultivars of S. tuberosum and others genera of the Solanaceae family were used.

Palabras clave : Anatomy of vegetative organ; in vitro conditions; Solanum tuberosum.