Response of Citrus volkameriana (L.) plants to different Mn concentrations under hydroponic conditions.
- Author(s): Papadakis, Ioannis
- Sotiropoulos, Thomas
- Giannakoula, Anastasia
- Antonopoulou, Chrysovalantou
- Therios, Ioannis
- et al.
Plant growth parameters, concentration of proline and carbohydrates in leaves and roots, and total uptake of Mn, Fe, Zn, K, Ca and Mg were determined in Citrus volkameriana (L.) plants after 43 days of growth in nutrient solutions containing 0, 2, 14, 98 or 686 μM Mn. The highest plant growth was observed under 2 μM Mn, while the lowest one under 686 μM Mn. Compared to the treatments 2 and 14 μM Mn, significantly lower concentrations of carbohydrates were found in the leaves and roots of plants grown under 0 or 686 μM, and 0, 98 or 686 μM Mn, respectively. Proline concentration in both leaves and roots was increased by increasing Mn concentration in the nutrient solution. This increase was stronger for the roots (linear correlation) than for the leaves. Mn concentrations in plant tissues and total Mn uptake per plant were progressively increased by increasing Mn concentration in the nutrient solution. However, the total uptake of K, Ca, Mg, Fe and Zn was significantly decreased when the nutrient solution contained 98 or 686 μM Mn, compared to the treatments 0-2 μM Mn. Finally, by increasing Mn concentration in the nutrient solution, plants tended to retain more Ca, Mg and Fe in the roots, and to allow more Zn to be transported to the shoot.