Figure 1From: PollenCALC: Software for estimation of pollen compatibility of self-incompatible allo- and autotetraploid speciesScheme of model differences for self-incompatible species with a S-Z system. Model I: any different allele at either S or Z in the pollen different from S or Z on the pistil makes pollen is compatible. Model II: any S-Z allele combination present in the pollen grain that matches the pistil makes pollen incompatible.Back to article page