Genetics, Vol 137, 783-789, Copyright © 1994

INVESTIGATIONS

Genetic and Maternal Variation for Heat Resistance in Drosophila from the Field

N. L. Jenkins and A. A. Hoffmann
Department of Genetics and Human Variation, La Trobe University, Bundoora, Victoria 3083, Australia

In Drosophila, field heritability estimates have focused on morphological traits and ignored maternal effects. This study considers heritable variation and maternal effects in a physiological trait, heat resistance. Drosophila were collected from the field in Melbourne, Australia. Resistance was determined using knock-down time at 37{deg}. Drosophila melanogaster was more resistant than Drosophila simulans, and males tended to be more resistant than females. Field heritability and maternal effects were examined in D. simulans using the regression of laboratory-reared F(1) and F(2) onto field-collected parents. Males from the field were crossed to a laboratory stock to obtain progeny. The additive genetic component to variation in heat resistance was large and significant, and heritability was estimated to be around 0.5. A large maternal effect was also evident. Comparisons of regression coefficients suggested that the maternal effect was not associated with cytoplasmic factors. There was no correlation between body size (as measured by wing length) and heat resistance. Unlike in the case of morphological traits, the heritability for heat resistance in nature is not less than that measured in the laboratory.

This article has been cited by other articles:

				D. Lerman and M. Feder Laboratory selection at different temperatures modifies heat-shock transcription factor (HSF) activation in Drosophila melanogaster J. Exp. Biol., January 1, 2001; 204(2): 315 - 323. [Abstract] [PDF]