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Plants grown in salt-affected soils may suffer from limited available water, ion toxicity, and essential plant nutrient deficiency, leading to reduced growth. The present experiment was initiated to evaluate how salinity and soil zinc (Zn) fertilization would affects growth and chemical and biochemical composition of broad bean grown in a calcareous soil low in available Zn. The broad bean was subjected to five sodium chloride (NaCl) levels (0, 10, 20, 30, and 40 m mol kg 21 soil) and three Zn rates [0, 5, and 10 mg kg 21 as Zn sulfate (ZnSO 4 ) or Zn ethylenediaminetetraaceticacid (EDTA)] under greenhouse conditions. The experiment was arranged in a factorial manner in a completely randomized design with three replications. Sodium chloride significantly decreased shoot dry weight, leaf area, and chlorophyll concentration, whereas Zn treatment strongly increased these plant growth parameters. The suppressing effect of soil salinity on the shoot dry weight and leaf area were alleviated by soil Zn fertilization, but the stimulating effect became less pronounced at higher NaCl levels. Moreover, rice seedlings treated with ZnSO 4 produced more shoot dry weight and had greater leaf area and chlorophyll concentration than those treated with Zn EDTA. In the present study, plant chloride and sodium accumulations were significantly increased and those of potassium (K), calcium (Ca), and magnesium (Mg) strongly decreased as NaCl concentrations in the soil were increased. Moreover, changes in rice shoot Cl 2 , Na + , and K + concentrations were primarily affected by 3046 the changes in NaCl rate and to a lesser degree were related to Zn levels. The concentrations of Cl 2 and Na + associated with 50% shoot growth suppression were greater with Zn-treated plants than untreated ones, suggesting that Zn fertilization might increase the plant tolerance to high Cl 2 and Na + accumulations in rice shoot. Zinc application markedly increased Zn concentration of broad bean shoots, whereas plants grown on NaCl-treated soil contained significantly less Zn than those grown on NaCl-untreated soil. Our study showed a consistent increase in praline content and a significant decrease in reducing sugar concentration with increasing salinity and Zn rates. However, Zn-treated broad bean contained less proline and reducing sugars than Zn-untreated plants, and the depressing impact of applied Zn as Zn EDTA on reducing sugar concentration was greater than that of ZnSO 4 . In conclusion, it appears that when broad bean is to be grown in salt-affected soils, it is highly advisable to supply plants with adequate available Zn.

Silicon (Si) is one of the most abundant elements in the earth's crust, although its availability may be affected by some edaphic and abiotic factorssuch as soil moisture and salinity. In a laboratory experiment, effects of silicon (Si), salinity, and soil moisture on changes of extractable Si, iron (Fe), and manganese (Mn) concentrations were investigated on a sandy loam calcareous soil. The experiment was arranged as a factorial completely randomized design with three replications. Two levels of Si (8 and 200 mg per kg of soil), three salinity levels [0.46 dS m −1 , 8 dS m −1 as sodium chloride (NaCl), and 8 dS m −1 as four-salt combination], two soil moisture regimes (-20 kPa and waterlogged), and four incubation times (0, 7, 30, and 45 days) were applied. Salt composition consisted of sodium chloride, sodium sulfate, calcium chloride, and magnesium sulfate at a molar ratio of 4:2:2:1. Acetic acid-extractable Si, Fe, and Mn were determined after 0, 7, 30, and 45 days of incubation. Waterlogging caused significant increase in the extractable Si, Fe, and Mn. Soil salinity of 8 dS m −1 , only in the form of sodium chloride, resulted in a marked decrease in extractable Si, Fe, and Mn. Silicon addition enhanced the soil Si concentration, with no effect on Fe and Mn. Equilibrium time for Si and Fe was 30 days, whereas Mn concentration reached to a constant level after 1 week of waterlogging. It was concluded that Si, Fe, and Mn fertilizers should be applied in sufficient amounts to the saline soils to prevent their deficiencies in plants. Meanwhile, overfertilization in waterlogged conditions must be avoided, because of the probability of nutrient imbalance or toxicity.

The effect of different iron fertilization methods on yield and some fruit quality parameters of the date-palm variety 'Piarom' was studied in a calcareous soil of Hormozgan Province in Iran. The trees were 12 years old and the treatments comprised of: 1-control, 2-surface placement of Fe-EDDHA in the soil with two levels, 3-deep placement of FeSO 4 in the soil (Chalkood method) with two levels, and 4-injection of FeSO 4 solution into the trunk of trees with four levels. The experiment was accomplished as a randomized complete blocks design with nine treatments and three replications during four years Injection of 25 grams of FeSO 4 into the trunk resulted in the highest yield, having considerable differences with the other treatments. The maximum concentration of iron, as well as the highest Brix index and reducing sugars content were obtained in trees injected with a solution of FeSO 4 , showing no significant differences between different levels of FeSO 4. Therefore, it can be concluded that trunk injection is a more efficient method for iron fertilization of date palms grown in calcareous soils. Moreover, the best injection level was 25 grams FeSO 4 tree-1. 

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