Optimisation of a species-specific primer set to quantify the soybean cyst nematode, Heterodera glycines, in soil using real-time PCR

Summary We previously reported a real-time PCR primer set (SCN) that is specific to the soybean cyst nematode Heterodera glycines, a major nematode pest in soybean production in Japan. However, the primer set also amplified the related species H. trifolii and H. schachtii, whose presence was recently reported in Japan. The objective of this study was to optimise a primer set to be more specific for quantification of H. glycines. The newly optimised primer set (SCNnew) amplified H. trifolii and H. schachtii at amplification efficiencies less than 1% of H. glycines. Surveys for H. glycines in different green soybean fields in Japan demonstrated that most fields judged to contain low densities of H. glycines based on the SCN primer set were not actually infested with H. glycines. The SCNnew primer set quantifies H. glycines in soil more precisely.