Droplet Digital PCR for Absolute Quantification of Plant Pathogens

Droplet digital PCR is the recent technological innovation that can detect up to a single gene copy. It features ease of use, precision, specificity and reproducibility for absolute quantification and gene expression studies than other ddPCR formats. ddPCR is a direct method to determine absolute quantification of target genes without the need of external standards. It is independent of amplification efficiency bias observed with quantitative PCR. ddPCR amplification of a sample is carried out in thousands of partitioned water-oil emulsion droplets and presence or absence of the target in each droplet is determined digitally by fluorescence at the end-point of amplification. Here, we discuss ddPCR applications of plant pathogens using citrus pathogens in duplex and triplex assays.