Spirulina platensis (Cyanophyta)'in gelişimine suni ligand EDTA (ethylenediaminetetraacetate) ve iki farklı Fe(Fe+2 ve Fe+3) formunun etkisi The effect of two different Fe forms (Fe+2 ve Fe+3) and artificial ligand EDTA (ethylenediaminetetraacetate) on the growth of Spirulina platensis (Cyanophyta)