Self-Compatibility Inheritance in Tomatillo (Physalis Ixocarpa Brot.)

One of the main limiting factors to improve tomatillo is the presence of self-incompatibility which has been reported to be gametophytic. In an early research, a self-compatible plant was found in the Rendidora landrace and this allowed us to investigate the inheritance of self-compatibility gene (s) in tomatillo. The following crosses were performed: self-compatible x self-incompatible, self-compatible x self-compatible and self-incompatible x self-incompatible and their respective reciprocal crosses. Segregation ratios on self-compatibility versus self-incompatibility in their offspring indicate that self-compatibility is not inherited via cytoplasm, so the responsible gene is located in chromosomes. The inheritance of self-compatibility is due to a single dominant gene (S_c) which is a mutation at the S locus. Self-compatible individuals are strictly heterozygous (S_c,4) and finally, the self-compatibility allele (S_c), in the male side (S_c,4), seems to be non functional when self-pollinating the S_c,4 stigma. A single gene controlling stem pubescence was also found.