Fig. 1

Standard curve from quantitative multiplex real-time PCR by plotting the threshold cycle (Ct) versus the log-transformed DNA concentrations. a Relationship between fungal biomass introduced in soil and fungal DNA quantified by real-time PCR for Plasmopara viticola oospores. b, c a tenfold dilution series of P. viticola DNA (10¹–10^–4 ng/µL) (b) and Vitis vinifera DNA (10²–10^–3 ng/µL) (c) was analyzed in triplicate by real-time PCR. The linear relationship between log-transformed DNA and the cycle threshold (Ct) values was determined for both P. viticola (b) and V. vinifera (c). Each data point represents five replications per concentration level for each test. The amplification efficiency was calculated as \({\mathbf{E}} = 10^{{\left( {\frac{1}{{ - {\mathbf{slope}}}}} \right)}} - 1\)