Evaluation of microbial inoculation on qualitative and quantitative characteristics of centaurea cyanus in a cd-contaminated soil

Recently, rhizospheric microorganisms such as arbuscular mycorrhiza fungi (AMF) and plant growth promoting bacteria (PGPR) are in use to increase plant growth and plant tolerance to heavy metals. In this study, the effects of AMF and PGPR inoculation were evaluated on uptake of some elements and physiological properties of Centaurea (Centaurea cyanus) in a Cd contaminated soil. This study carried out in a greenhouse condition as a factorial experiment based on a randomized complete block design with three replications. Four levels of Cd concentrations (0, 250, 500 and 1000 mg kg-1) and three levels of microbial treatments (control, AMF (mixture of Glomus and Rhizophagus speciesincluding R. intraradices, G. mosseae and G. fasciculatum) and PGPR (mixture of Pseudomonas species includeing P. putida, P. fluorescens, and P. aeruginosa)) were included in the study. Results indicated that by increasing Cd concentrations, plant growth, Fe, Cu and Zn concentrations in shoot of Centaurea, chlorophyll and carotenoeids contents, plant height and microbial respiration decreased, while proline content and Cd concentration in shoot and root of Centaurea significantly (p