Seedlings of ‘Pineapple’ sweet orange [ Citrus sinensis (L.) Osbeck] (Swt), Cleopatra mandarin ( C. reshni Hort ex Tan) (Cleo)], and trifoliate orange [ Poncirus trifoliata (L.) Raf.] (Tri) were grown from seed for 10 months in 2-liter containers of native Candler fine sand in a glasshouse, watered two times per week, and fertilized weekly with a complete nutrient solution. NaCI at 0, 15, 30, or 60 mM was added to the watering solution for 2 additional months. Increases in salinity decreased hydraulic conductivity of roots, transpiration rate, leaf water potential, and root growth. The effect of salinity on mineral composition of tissues was rootstock-dependent. High salinity leaves of Tri had the highest N, K + , and Cl − but the lowest Na + , whereas Tri roots had the highest Na + at the highest salinity. High-salinity Cleo leaves had the lowest Cl − and K. All seedlings survived −4°C for 6 hr in a controlled freeze test. Salinity decreased leaf loss, except in the deciduous Tri, in which 60 mM NaCI may have been excessive. Thus, moderate salinity treatment can reduce growth and modify water and mineral nutrient relations so as to increase cold hardiness of certain Citrus species.
No takes yet. Share an insight, caveat, or question.
Syvertsen et al. (1988) studied this question.