Table 1.
List of the primers used for quantitative real-time PCR.
Fig 1.
Visual symptoms in leaves of Citrus macrophylla seedlings grown for 25 days in B-normal (50 μM, Ct) and B-toxic (400 μM, +B) nutrient solutions.
Table 2.
Growth parameters [dry weight (DW, mg) and length (cm)], total boron concentration ([Bt], μg g-1 DW) and total B content (Bt, μg) measured in roots, stems and leaves of Citrus macrophylla seedlings grown for 25 days in B-normal (50 μM, Ct) and B-toxic (400 μM, +B) nutrient solutions.
Fig 2.
Chlorophyll (Ch) a, b and total content (µg g FW−1) measured in fully developed leaves of Citrus macrophylla seedlings grown for 25 days in B-normal (50 μM, Ct) and B-toxic (400 μM, +B) nutrient solutions.
Values are the means ± SE of six independent plants per treatment (n = 6). For a comparison of means, an ANOVA followed by the LSD test, calculated at 95% confidence level, was performed. Different letters in the same row indicate significant differences between treatments (P <0.05).
Fig 3.
Relative expression of NIP5, PIP1 and PIP2 genes measured by real-time RT-PCR analysis, in roots and leaves of Citrus macrophylla seedlings grown for 25 days in B-normal (50 μM, Ct) and B-toxic (400 μM, +B) nutrient solutions.
Values are the means ± SE of three independent experiments (n = 3). For a comparison of means, an ANOVA followed by the LSD test, calculated at 95% confidence level, was performed. Different letters in the same organ indicate significant differences between treatments (P <0.05).
Fig 4.
Relative expression of CmBOR1 and BOR4 genes measured by real-time RT-PCR analysis, in roots and leaves of Citrus macrophylla seedlings grown for 25 days in B-normal (50 μM, Ct) and B-toxic (400 μM, +B) nutrient solutions.
Values are the means ± SE of three independent experiments (n = 3). For a comparison of means, an ANOVA followed by the LSD test, calculated at 95% confidence level, was performed. Different letters in the same organ indicate significant differences between treatments (P <0.05).
Fig 5.
Relative expression of TIP5, V-PPiase and V-ATPase A genes measured by real-time RT-PCR analysis, in roots and leaves of Citrus macrophylla seedlings grown for 25 days in B-normal (50 μM, Ct) and B-toxic (400 μM, +B) nutrient solutions.
Values are the means ± SE of three independent experiments (n = 3). For a comparison of means, an ANOVA followed by the LSD test, calculated at 95% confidence level, was performed. Different letters in the same organ indicate significant differences between treatments (P <0.05).
Fig 6.
Boron concentration ([Bf], μg g-1 DW) and boron content (Bf, μg) in (A) soluble in water, (B) soluble in organic solvents and (C) insoluble fractions measured in roots and leaves of Citrus macrophylla seedlings grown for 25 days in B-normal (50 μM, Ct) and B-toxic (400 μM, +B) nutrient solutions.
Values are the means ± SE of three independent experiments (n = 3). For a comparison of means, an ANOVA followed by the LSD test, calculated at the 95% confidence level, was performed. Different letters indicate significant differences for each parameter and within each plant organ (P <0.05).
Table 3.
Proline (µmol g FW−1) and malonaldehyde (MDA, nmol g FW−1) concentrations measured in roots and leaves of Citrus macrophylla seedlings grown for 25 days in B-normal (50 μM, Ct) and B-toxic (400 μM, +B) nutrient solutions.