ALMOND SELF-INCOMPATIBILITY GENETICS: RECENT PROGRESS AND FUTURE PROSPECTS

Self-incompatibility in almond is of the gametophytic type and controlled by a multigene complex named the S locus, expressed in the pistil (S-RNase) and in the pollen (SFB protein). Despite of being described as a self-incompatible species, self-compatible almond accessions have been identified.
As a result of the intensive research carried out in the last years on self-incompatibility (SI) genetics of this and other Prunus species, efficient PCR primers were designed.
These primers allowed the molecular identification and characterization of several S-haplotypes in almond.
This information resulted very useful to update the table of cross-incompatibility groups and also for phylogenetic studies in Prunus. Moreover, these molecular tools are routinely applied in some almond breeding programmes for the early selection of self-compatible individuals.
Since the identification of self-compatible almonds, several studies have tried to explain this failure in the functioning of the SI system.
Recent studies have pointed out that unknown components other than S-RNase and SFB proteins should be involved in the SI system.
Nowadays the efforts are focused on the identification of these other genes/proteins and their possible interactions by carrying out genome studies and comparative proteomic assays.

VI International Symposium on Almonds and Pistachios

E. Ortega, E.M. Gómez, F. Dicenta

Prunus dulcis, self-(in)compatibility, pistil S gene, pollen S gene, S-RNases, SFB, modifier factors