Author(s): M.A. Elhaak
Article publication date: 1999-04-01
Vol. 17 No. 1 (yearly), pp. 95-109.
DOI:
122

Keywords

water uptake, callus growth, Abscisic acid

Abstract

Callus from the desert plant Gymnocarpos decandrum was developed and recultured in a medium supplemented with Abscisic acid (ABA). Growth, osmotic potential, water content and some osmoregulatory metabolites were analyzed. Addition of ABA in the callus medium enhanced a callus growth without counteracting other growth regulators in the medium. Added ABA increased callus water uptake, important in resing imposed stresses. The acid also enhanced osmoregulation, regardless of callus water content, by accumulation of some metabolites and not by nutrient elements. The latter were exhausted by increased callus growth activity. Apart of this, there was an increase in the amino acids which reversed ABA inhibitory effect and a decrease in those which enhanced its effect; even some of them could not be detected with time of ABA application. The accumulation of proline was a function of ABA and not of water content, while the reverse was true for quaternary ammonium compounds (QAC).