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BA 29 and EMA (Cydonia oblonga L.) plants were grown in a 1:1 sand:perlite mixture and irrigated with nutrient solutions containing two B concentrations (0.025 and 0.2 mM) combined with two salinity (electrical conductivity, EC) levels (0.75 and 4 dS· m-1). The lowest growth of plants was recorded when 0.2 mM B was combined with 4 dS·m-1 in the nutrient solution. As salinity (EC) level increased from 0.75 to 4 dS·m-1, P, Ca and Fe concentrations of leaves decreased. The potassium concentration of leaves of both rootstocks increased, as salinity levels (induced by KCI) increased. The two quince genotypes respond differently for the same treatments, indicating a genotypic effect. [ABSTRACT FROM AUTHOR]

The effect of salinity on potassium (K), calcium (Ca), magnesium (Mg), phosphorus (P), and nitrate–nitrogen (NO3–N) concentration and partitioning was studied in a hydroponic culture of own-rooted grapevine, cultivar Thompson seedless (Vitis vinifera L.), or grafted onto the rootstocks 110R, 140Ru, 1103P, SO4, and 41B. Plants were grown in 25 L pots and exposed to salinity by irrigation for a period of 60 days with 50% Hoagland No. 2 nutrient solution also containing 5, 25, 50, or 100 mM NaCl. At the end of the stress period, concentrations of K, Ca, Mg, P, and NO3–N were measured in leaf blades, leaf petioles, shoots, trunk, and roots. Leaf blade, leaf petiole, and shoot P concentrations increased with salinity, whereas that of NO3–N and K decreased in all parts of the vine. Salinity had no effect on shoot Ca and Mg, trunk P and Mg, and root P, Ca, and Mg concentrations. Rootstock genotype significantly influenced the nutrient concentrations of different vine organs, except those of blade and root Ca, petiole Mg and NO3–N, shoot P and NO3–N, and trunk P and NO3–N. [ABSTRACT FROM AUTHOR]

• Pomegranate cultivar (cv.) 'Grenada' was the most susceptible under all saline conditions. • Pomegranate cvs. 'Wonderful' and 'Ermioni' may be cultivated under saline conditions. • Concentrations of Ca and Mg in leaves significantly reduced under KCl and K 2 SO 4 salts. • The highest concentrations of KCl and K 2 SO 4 (75 mM) decreased the chlorophyll concentration. The present investigation assesses the behavior of three pomegranate cultivars (Punica granatum L.) ('Wonderful', 'Ermioni' and 'Grenada') under increased concentrations of three salts (NaCl, KCl and K 2 SO 4) after 150 days of growth in vivo conditions. The aim of this research was to study the nutrient accumulation and distribution in leaves and roots and its effects on total chlorophyll (a + b), carotenoids, photosynthetic rate and stomatal conductance of leaves. In general, high salt supply of KCl and K 2 SO 4 led to significant decline in Ca and Mg concentration in leaves in all cultivars. 'Grenada' found with the highest concentration of Mn in leaves under all salt treatments. Regarding the roots, 'Wonderful' had the highest Mg concentration at 25, 50 and 75 mM of KCl and K 2 SO 4 , while 'Ermioni' had the maximum Ca concentration in roots. Chlorophyll concentration was reduced by the effect of KCl and K 2 SO 4 salts in all cultivars. Furthermore, K 2 SO 4 salt significantly reduced carotenoid concentration in leaves in all cultivars, especially 'Wonderful' showed 63.36 % reduction. 'Grenada' had the lowest photosynthetic rate and K 2 SO 4 salt exerted a significant effect in all cultivars. Regarding stomatal conductance, 'Ermioni' had the highest values with KCl and K 2 SO 4 salt treatments, while 'Grenada' was the most affected cultivar by all salts and at all concentrations. Our findings show the considerable potential of exploiting saline soils to obtain pomegranate plants with higher level of salt tolerance. Furthermore, our results suggest that 'Wonderful' and 'Ermioni' pomegranate cultivars may be cultivated also under marginal saline conditions. [ABSTRACT FROM AUTHOR]

One-year-old self-rooted cuttings of three Citrus limon cultivars (Nouvel Athos, Lisbon, Maglini) were grown in 1 L black plastic bags, containing a mixture of sand: perlite (1:1), in order to investigate: i) if genotypic differences to salt stress existed, ii) if KNO 3 can alleviate salinity stress, iii) the role of carbohydrates (such as the sugars fructose, glucose and sucrose) and proline as possible osmoregulators in C. limon osmoprotection, and iv) if genotypic differences to salt stress tolerance exist among the 3 studied cultivars. The experiment included 3 treatments: i) control (C), i.e. 25% modified Hoagland (No2) solution (MHS)-NaCl, ii) T1, 25% MHS+80 mM NaCl, iii) T2, 25% MHS+80 mM NaCl+5 mM KNO 3 . Plant growth was negatively affected by high NaCl (T1); the highest Cl and Na quantities have been absorbed by Lisbon, while the lowest ones by Maglini. Salt stress reduced macronutrient and Zn concentrations, as well as the total carbohydrate concentration, and increased peroxidase (POD) activity and chlorophyll fluorescence in the leaves of the 3 C. limon cultivars studied; five mM KNO 3 application alleviated the harmful effect of salt stress on leaf total carbohydrate concentration and leaf N and K concentrations. Sucrose was dramatically reduced in all the three genotypes studied, while leaf fructose concentration was significantly increased in Nouvel Nouvel Nouvel Athos and Maglini under salt stress. Leaf proline concentration of Maglini was significantly decreased by the high NaCl concentration, while Nouvel Athos and Lisbon had high proline concentration in their leaves. In conclusion, from the significantly decreased levels of proline for Maglini, together with the greatest reduction of the ratio F v /F m and the least enhancement of POD activity-compared to the other two cultivars-it can be concluded that Maglini was more susceptible to salinity, and should not be preferred for cultivation under NaCl stress. Finally, rich KNO 3 application alleviated the harmful effect of NaCl stress, thus it is highly recommended for use by the growers in areas with salt problems. [ABSTRACT FROM AUTHOR]