Effect of NaCl salinity on growth, leaf gas exchange, and mineral composition of grafted mango rootstooks (var. '13-1' and 'Turpentine')

The differential response of graft combinations between two mango rootstock cultivars ('13-1' and 'Turpentine') to NaCl salinity (0 and 30 mM NaCl add ed) was assessed. Two growth-flushes long cuttings were rooted and then gra fted reciprocally to raise four graft combinations between the two rootstoc ks. Nongrafted cuttings were also tested. CO2 assimilation and transpiration decreased in all graft combinations duri ng salinization. The strongest reduction was found in the combination 'Turp entine' grafted on '13-1' as a rootstock. Also the strongest reduction in s hoot growth and the highest Cl- contents in leaves were found in this graft combination, indicating that '13-1' as a rootstock was not able to protect the salt-sensitive scion 'Turpentine'. '13-1' as a scion was able to maint ain a significantly higher K+/Na+ ratio in the leaves, while as a rootstock it had no such effect on the scion.