Potassium Affects Sodium Content in Tomato Plants Grown in Hydroponic Cultivation under Saline-sodic Stress

in HortScience
View More View Less
  • 1 Dipartimento Biologia Piante Agrarie, Università di Pisa, Italy Viale delle Piagge 23, I-56124 Pisa, Italy
  • | 2 Dipartimento Biologia Piante Agrarie, Università di Pisa, Italy Viale delle Piagge 23, I-56124 Pisa, Italy

The tomato cultivars Edkawi and UC 82B (Lycopersicon esculentum Mill.) were grown hydroponically in a solution [electrical conductivity (EC) 2.4 dS·m-1] containing 150 mm Na (EC 11.4 dS·m-1), 37 mm of K (EC 14.1 dS·m-1), or 75 mm of K (EC 19.7 dS·m-1). The leaf Na content of `Edkawi' and `UC 82B' reached values of 1717 and 2022 mmol·kg-1 dry weight at EC 19.7 dS·m-1, respectively. The high levels of K in the hydroponic solution reduced the Na concentration in the roots, petioles, and stems, but not in the leaves. Potassium concentrations in the petioles of `Edkawi' and `UC 82 B' reached values of 2655 and 2966 mmol·kg-1 dry weight, respectively. At these elevated ECs, the Ca concentrations in the leaves of `Edkawi' and `UC 82B' were 30% and 40% lower than in the control, respectively. The elevated rates of K improved the fruit: flower ratio of `UC 82B', but the high salinity of the solution reduced yields significantly. Plant fresh weight and root dry weight of `UC 82B' were most affected by high EC levels. The elevated levels of K used in this study did not increase yield, but K ions can adjust to Na uptake.

Contributor Notes

To whom requests for reprints should be addressed. E-mail address: mlipucci@agr.unipi.it
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 172 45 5
PDF Downloads 368 114 17