IONIC RELATIONS OF AEROPONICALLY-GROWN OLIVE GENOTYPES, DURING SALT STRESS

Two olive (Olea europaea L.) genotypes, 'Frantoio' and 'Leccino', were exposed to increasing concentrations of NaCl (0-30-60-120 mM) in an a eroponic cultivation system for 60 days. Dry weights and sodium and po tassium contents of apical and basal leaves, new and old wood, and roo ts were measured to determine Na uptake rate, Na translocation rate an d K-Na selectivity ratio (S-K,S-Na). 'Frantoio' showed a higher salt r esistance than 'Leccino'. 'Frantoio' and 'Leccino' had a similar Na up take rate, but largely differed for Na translocation to the shoot. Fur thermore 'Frantoio' exhibited a higher K-Na selectivity than 'Leccino' at both whole plant level and above all at the level of shoot system. Resistance mechanism of 'Frantoio' is probably related to Na esclusio n by roots and to the ability to maintain an appropriate K/Na ratio in actively growing tissues.