Selection of Somatic Hybrids and Cybrids - Proper selection of the hybrid cells or fusion products after fusion treatment is necessary since the protoplast populations consist of a heterogeneous mixture of unfused parental types, homokaryons, and heterokaryons. This is because the fusion induced by various methods is random and uncontrolled.
Generally, 20-25% protoplasts may be involved in a fusion event although heterokaryon formation as high as 50-100% has been reported. The low number of true hybrid cells formed may get lost in the population of actively dividing homokaryotic fusion products and unfused parental protoplasts.

Hence, selective recovery of the few hybrid cells formed from the mixed population of regenerating protoplasts is a key factor in successful somatic hybridization. Many selection procedures are employed.