Histological and exomorphological changes occuring during in vitro tuberization of potato cv. Spunta.

MELCHIORRE, M.; CASANO, L.M., MORICONI, DN

BIOCELL

Año: 1997 p. 119 - 127

0327-9545

Abstract The aim of this work was study the exomorphological and histological changes occurring during in vitro tuberization of potato cv. Spunta. In order to stablish optimal conditions for inducing microtubers, two types of explants, single node-stem cuttings and isolated plagiotropic stolon-like cuttings, were grown in the presence of 22 ìM benzyladenine (BA) and 3.2 mM 2- chloroethyl trimethyl amonium chloride (CCC) added to MS medium, under continuos darkness at 21 °C. Stem cuttings developed sessile microtubers exhibing a relative high growth rate. Contrastingly, the growth rate of microtubers from isolated stolons was lower, allowing us to distinguish four distinct stages in the microtuberization process: (I) development of a thin and cylindrical stolon, (II) curvature and enlargement of the subapical region of stolon, (III) tuber filling as consequence of the inhibition of the stem elongation and the proliferation of storage tissues, and (IV) tuber maturation, in which the highest starch accumulation occurred and tuber tend to separate from stolon. Main histological features of different steps were analyzed.