Abstract
In S. commune the frequency of recombination between the two subunits, alpha and beta, of the B incompatibility factor is genetically controlled. Analysis of the progeny obtained from crosses between high- and low-recombining strains indicates that the gene controlling recombination frequency in the B factor is linked to the B factor itself, approximately nine map units from Bbeta. This gene, called B-rec-1, does not affect the recombination frequency in an unlinked region (between the subunits of the A incompatibility factor) or in a region contiguous with the B factor (between Balpha and the morphological marker dome-2).