GENETIC VARIATION OF THE HYBRID CROSSABILITY BETWEEN DROSOPHILA MELANOGASTER AND D. SIMULANS

Abstract

The genetic variation of the hybrid crossability between D. melanogaster females and D. simulans males was examined by using 8 geographical strains of D. simulans from Japan. The hybridization was measured by insemination rate, egg to adult viability, and the number of hybrid progeny. The most experiments were undertaken with Oregon-R melanogaster females and various D. simulans male strains. The variation among D. simulans strains was clearly detected in these measurements and they were in large part positively correlated with each other. The temperature sensitivity of the hybrid varied from strain to strain of D. simulans, and was not ascribed to the geographical origin of the strain. D. melanogaster females were also variable in the hybrid crossability. Six D. melanogaster strains were significantly different in the insemination rate. A significant variance due to the interaction between D. melanogaster .times. D. simulans was also detected. The yellow mutant of D. melanogaster females showed an excellent receptivity to D. simulans males, and the yellow locus itself seemed to respond it.