Flow cytometric analysis of the fluorescence distribution after protoplast staining and fusion. The parent and hybrids with different fluorescent dyes are represented as dot plots in the figure. Based on the different excitation and emission parameters, the sorting results were divided into four regions. R2 and R5 detected strains with single Nuclear Red and Nuclear Green, respectively. R3 detected possible hybrid strains with Nuclear Red and Nuclear Green. R4 was used as control to detect the blank strains. a Protoplasts of P. anomala without staining; b protoplasts of P. anomala stained by Nuclear Red; c protoplasts of P. anomala stained by Nuclear Green; d double-positive hybrid cells exhibiting high intensity fluorescence for Nuclear Red and Nuclear Green.