PRODUCTION OF HAPLOID-HAPLOID CHIMERAS BY SPERM INJECTION IN THE SAWFLY, ATHALIA-ROSAE (HYMENOPTERA)

Mature unfertilized eggs (oocytes) dissected from the ovary of the saw fly Athalia rosae (Hymenoptera) begin parthenogenetic development if e xposed to distilled water and produce haploid males. Injection of sper m into mature oocytes through the anterior pole resulted in karyogamy in a fraction of cases which developed as diploid females. No haploid- haploid chimeras due to independent participation of the injected sper m in development were produced. When sperm were injected through the p osterior pole, however, fertilization never occurred but haploid-haplo id chimeras were produced in a smaller fraction of cases. Both egg nuc leus-derived and injected sperm-derived nuclei contributed in forming the germ cells of the chimeric males.