Abstract
Using Petunia hybrida, it was attempted to produce new S alleles by selfing.
The inbred progenies which were self-incompatible were reciprocally crossed with their parents. As a result no new S specificity was produced, but a part of the progenies showed various grades of fertility only when they were used as the female. Such unilateral pseudo-compatibility was not observed between the hybrid progenies and their parents.
An interpretation for the phenomenon‘unilateral pseudo-compatibility’was given.
