Availability of zinc in the rhizosphere of corn in texturally different contaminated soils treated with chelators

Rhizosphere processes have a major impact on zinc (Zn) availability in soils. The chemical and biological characteristics of the rhizosphere soils can be very different from those of the bulk soils. In peresent study, the effects of EDTA, citric acid and poultry manure extract (PME) on availability of Zn in the rhizosphere of corn (hybrid (KSC.704)) investigated in two texturally different contaminated soils as factoriel in a completely randomized design with three replications in greenhouse condition.
Citric acid and EDTA were used at concentrations level 0, 0.5 and 1 mmol kg-1 soil and poultry manure extract at concentrations level 0, 0.5 and 1 g kg-1 soil. Three seeds of corn were plant in the rhizobox. After 10 weeks, plants were harvested and rhizosphere and bulk soils were separated. Dissolved organic carbon (DOC), microbial biomass carbon (MBC) and available Zn (by using 4 chemical procedures including DTPA-TEA, AB-DTPA, Mehlich3 and rhizosphere-based method) were determined in the rhizosphere and bulk soils.
Rhizosphere soils properties was different with bulk soils. In both soils, the results indicated that DOC and MBC in the rhizosphere were significantly (p In both soils, Zn extracted by different methods in the rhizosphere were significantly (p