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Copper (Cu) is a necessary micronutrient for crops and its availability in calcareous soils is low. Phytoavailability of Cu depends on the relative distribution of different chemical Cu forms in soil, which is function of soil properties. In this greenhouse research, total soil Cu fractionated into different forms by sequential extraction procedure in 21 surface soil samples of East Azarbayjan province that varied in physical and chemical properties. According to the results, different Cu fractions concentration were as: Residual copper (Cu-Res) > Crystalline Fe oxides bound (Cu-CFeOX) > amorphous Fe oxides bound (Cu-AFeox) > Oranically bound (Cu-OM) > Carbonates bound (Cu-Car) > soluble 笗Ⅺ砞榹 (Cu-Ex) > Mn oxide bound (Cu-Mnox). Correlation coefficient showed that the corn shoot dry matter, corn shoot copper concentration and corn shoot copper content hadn’t significant correlation with soil copper forms. Cu-Car, Cu-MnOX, Cu-AFeOX, and Cu-Res had a significant relationship with corn shoot and root copper concentration.

Iron (Fe) is the most important micronutrient for crops that has low availability in calcareous soils. Phytoavailability of Fe depends on the relative distribution of different chemical Fe forms in soil, which is function of soil properties. In this greenhouse research, total Fe fractionated into different forms by sequential extraction procedure was studied in 21 soil samples that varied in physical and chemical properties. According to the results, different Fe fractions concentration were as: Residual iron (Fe-Res)> iron associated with the crystalline iron oxides (Fe-CFeOX)> iron associated with the amorphous iron oxides (Fe-AFeOX)> manganese- oxide- associated Fe (Fe- MnOX)> organic matter-associated Fe (Fe-OM)> exchangeable iron (Fe-Ex) ≥ carbonates-bound iron (Fe-Car). Fe-Ex, Fe-OM, Fe-AFeOX, Fe-CFeOX, Fe-Res and available iron (Fe-DTPA) had a significant relationship with corn shoot and root dry matter, active iron content, chlorophyll index and shoot iron uptake. Correlation coefficient showed that the Fe-Ex, Fe-AFeOX and Fe-Res had a close and significant relationship with all measured agronomical traits of corn. It is concluded that, these forms of iron are probably the source of available iron for corn in studied soils.

This study was carried out to determine the effects of aqueous extracts of (cardaria draba L.) organs (root, stem, leaf and their mixture) on germination of sorghum. The experiment was laid out as a completely randomized design with factorial arrangement and in four replications in research lab of agricultural college at Birjand University in 2010. The treatments included aqueous extracts of root, stem, leaf and their mixture at concentration of zero (check), 10, 20, 40 and 80 percent. According to the results, extracts of different tissuess on germination and root length could be 5% on level, and the germination rate and number of lateral roots was significantly different at 1% percent. The effect of white top extract concentration on all measured traits were significant at 1%. Infact, different organs and concentrations of white top affects considerably prevential on germination of sorghum seeds. Similar results were observed in concentration of 80% by volume, So that the largest percentage of decline in sorghum seed germination (22.5%) were related to the recent treatment.