| Abstract: | Somatic incompatibility in two strains of the myxomycete Didymium iridis is controlled by at least 13 loci: seven fusion loci and six clear-zone loci. Details on correlating loci of the Hon 1 strain with Pan 1 loci are given and a unified nomenclature, applicable to both strains, has been developed from data presented in this paper. Although fusion loci generally prevent fusion between different plasmodial incompatibility phenotypes, studies on individual loci have shown that a limited transient fusion may occasionally take place. Thus, the differences between the fusion and clear-zone loci are not as distinct as once thought. However, the 13 somatic incompatibility loci are still easily designated as either fusion or clear-zone loci, and no locus has thus far been found with true intermediate function. Studies on individual locus function are also discussed. |
