Self-(in)compatibility of the almonds P. dulcis and P. webbii: detection and cloning of 'wild-type Sf ' and new self-compatibility alleles encoding inactive S-RNases.

Prunus dulcis, the almond, is a predominantly self-incompatible (SI) species with a gametophytic self-incompatibility system mediated by S-RNases. The economically important allele Sf, which results in self-compatibility in P. dulcis, is said to have arisen by introgression from Prunus webbii in the Italian region of Apulia.