Abstract:Based on the sequences of racy genes from Microcystis, a specific primer pair was determined. PCR-mediated detection of mcyB gene was developed and applied to the identification of potential microcystin produced from Microcystis strains in natural water bodies. The sensitivity of PCR method was investigated, and the detection limit was as few as 100 cells per reaction. The method does not require extraction of the genomic DNA of Microcystis, and does not need large volume of water samples. It is simple, sensitive, rapid and economical, which can be used for the detection of the toxic Microcystis strains in water sources for human consumption.