Hybrid dysgenesis in Drosophila: correlation between dysgenic traits.

Crosses between laboratory stocks and extractions from wild populations have recently been shown to produce non-reciprocal genetic aberrations commonly termed hybrid dysgenesis, which appear to arise from a nuclear cytoplasmic interaction. Female sterility is one aspect which has been investigated and both poor egg production (GD sterility) and low hatchability (SF sterility) have been shown to contribute. It has previously been suggested that these characters may have an independent action and causation. The results presented in this paper however, show a high degree of correlation in the response of SF and GD sterility to various developmental temperature regimes, with both forms of sterility showing an increase as the developmental temperature rises. For each character, the whole of the life cycle appears to be affected by changes in the developmental temperature although two stages were identified as being particularly sensitive. The results therefore suggest that these two characters have a common cause and the relationship between these and other dysgenic traits is discussed.