Quantitative real-time PCR standard curve for a 141 bp WSSV VP28 fragment. (A) Standard curve for real-time PCR. A ten-fold serially diluted 141 bp WSSV VP28 DNA fragment was amplified and analyzed in real-time (1.24 x 108 to 1.24 x 102 copies/μL). Quantification cycle (Cq) values were plotted against copy number to construct the standard curve. R2=0.999, and amplification efficiency (E) =1. (B) Representative amplification plot for WSSV VP28 DNA fragment dilutions.