Accumulation of Ions in Shoot and Seed of Quinoa (Chenopodium ‎quinoa Willd.) Under Salinity Stress

Quinoa (Chenopodium quinoa Willd.) is a high-nutrient halophyte suitable for ?cultivating in semi-arid climates and saline soils. The current study investigated the ?effect of various water salinities (EC_i) (i.e., 0.3, 10, 15, 20, and 25 dS m^?1) and different ?irrigation methods (IMs) on accumulation of calcium (Ca), magnesium (Mg), ?sodium (Na), and chloride (Cl) ions in shoot (stem+leaves) of quinoa at the end of vegetation (onset of flowering) and seed at the end of seed-filling. Therefore, 30 pots (five EC_i and two IM in three replications) were prepared with similar conditions. Considering that the salinity threshold value (STV) of quinoa varies during growth and is 8, 20 and 15 dSm^?1 at each of ?establishment, flowering, and seed-filling growth stages, the two IMs consisted of considering STV at each growth stage (T) and permanent irrigation by ?constant levels of EC_i(P). Results indicated that by increasing the EC_i from 0.3 to 25 dSm^?1 the amount of Na, Cl, and Mg in shoot increased 82.2%, 75.8%, and 8.7%, respectively, while Ca decreased 37.2%. In seeds, Na and Cl increased 43.3% and 50%, respectively, while Mg increased 8% and Ca did not change significantly. An increase in EC_i ?significantly changed ion accumulation content, especially at EC_i higher than STV, ?because it is the onset of damage due to salinity stress and particularly in? ??shoot compared to seed due to the halophytic properties of quinoa. The T ?method of irrigation was preferred due to less accumulation of Na and Cl in ?shoot and seed, and therefore less damage and loss, especially at higher ?salinities.?     

Comparative Study of DOP and CND Methods for Leaf Nutritional ‎Diagnosis of Vitis Vinifera in Iran

In this study, the norms for Vitis Vinifera have been derived and compared using the Compositional Nutrient Diagnosis (CND) and Deviation from Optimum Percentage (DOP) diagnose methods to determine the nutrient deficiency in Vineyards at Central Alborz region, Iran. A total of 200 leaf samples were collected during two years from Vitis Vinifera trees and nutrient concentrations of Mn, Zn, Fe, Mg, Ca, K, P, N, B, and Cu were measured. The results showed that there are differences between DOP and CND diagnosis methods. According to mean DOP indices for nutrient elements, the priority of the deficiency of elements was as follows: Mn > P > Ca > Fe > Cu. In addition, the CND standard norms were determined as F^c_i(V_N) = 32.34, F^c_i(V_P) = 34.49, F^c_i(V_K) = 48.58, F^c_i(V_Ca) = 54.39, F^c_i(V_Mg) = 64.11, F^c_i(V_Mn) = 19.71, F^c_i(V_Zn) = 47.64, F^c_i(V_Fe) = 53.32, F^c_i(V_Cu) = 32.44, F^c_i(V_B) = 41.59, and F^c_i(R_d) = 39.19 ton.ha^?1. The results also showed that there is the deficiency of manganese, nitrogen, iron, and phosphorus in vineyards. Therefore, the field observations due to the implications of apparent deficiencies of nutrient elements in the gardens of the region are more consistent with the DOP method.     

Inorganic and organic ligands induced changes in Pb sorption of arid ‎clay and calcareous loamy sand soils

The objective of this study was to investigate sorption, desorption, and immobilization of Pb in the clay and calcareous loamy sand soils treated with inorganic ligands (NO₃^?, Cl^? and H₂PO₄^?). Pb sorption was also determined in the presence of oxalate and citrate. The maximum Pb sorption capacities (q) ranged from 42.2 to 47.1 mmol kg^?1 for the clay soil, and from 45.2 to 47.0 mmol kg^?1 for loamy sand soil. It was observed that the binding energy constant (k) for Pb sorbed onto loamy sand soil (528–1061) is higher than that for clay soil (24.38–55.29). The loamy sand soil-sorbed greater quantities of Pb compared to the clay soil when initial pH was ≥ 3. However, it had lower sorption capacity at the lowest initial pH of 2. Additionally, the greatest Pb sorption and immobilization occurred in the soil treated with H₂PO₄. In the clay soil, the sorption of Pb was depressed at 0.1 mol kg^?1 of Cl^?, as compared with other ligands. Concerning organic acids, citrate ligand showed the highest decrease in Pb sorption. It could be concluded that the nature of Pb sorption can depend on the type and quantity of ligands present, as well as the soil type.