Antimycoplasmal Antibiotics and Hybrid Sterility in Drosophila paulistorum

Male hybrids between the Santa Marta and Mesitas strains of Drosophila paulistorum are sterile. The sterility can be partially alleviated by treatment of the Santa Marta mothers with the antimycoplasmal antibiotics tylosin tartrate and tetracycline hydrochloride. The proportions of hybrid males in which there are mature motile spermatozoa are higher in the progenies of drug-treated mothers than in the controls. Electron microscopy reveals mycoplasma-like bodies in the untreated controls, but not in the sons of the treated females. The mycoplasma-like symbionts appear to be implicated in the production of the sterility in the hybrid males.