Screening, Identification of Fungi with High Cadmium-Resistance and its Solubilization Capacity of Insoluble Phosphates

A fungus with high cadmium resistance was isolated from the soil polluted by e-waste primitive recycling activity by adding definite concentration of Cd (200 mg/L) as 3CdSO₄·8H₂O in the medium. The fungus belonged to Cochliobolus lunatus according to ITS rDNA sequences. This strain was able to grow well on PDA plate containing 2 000 mg/L Cd²⁺, and its cadmium resistance might be ascribed to the production of alkaline materials during its growth. Apart from Cd²⁺, this stain could tolerate Pb²⁺, Zn²⁺ and Cu²⁺ efficiently as well. The resistance decreased in the order of Zn²⁺, Cd²⁺>Pb²⁺>Cu²⁺>Co²⁺>Ni²⁺, Cr²⁺>Hg²⁺, Ag⁺. This strain could grow in the liquid medium with three different inorganic phosphates, and the phosphate solubilization capacity was in the order of Ca₃(PO₄)₂(104 mg/L)>AlPO₄ (86 mg/L)>FePO₄·4 H₂O (17 mg/L).