Oviposition site preferences in natural populations of Drosophila melanogaster.

BETTI, M.; SOTO, E. M.; E. HASSON

Raleigh, North Carolina, Estados Unidos.

Simposio; The American Genetic Association 2008 Symposium. Genetics and Genomics of Behavior.; 2008

The American Genetic Association

The election of an oviposition site by a insect female determines the breeding resource in which the progeny will grow up and this may directly affect larval fitness. The evolution of different oviposition site preferences may constitute the initial step of host race formation. Such preferences may be measured as the tendency of females to lay eggs on a particular host when given a choice. In this work, we search for genetic variation in oviposition site preference within and between populations of Drosophila melanogaster. Females were allowed to choose between Vitis vinifera (grape) and Citrus aurantium (orange), in flies derived from three allopatric localities. Ours results indicate that, though, in general, grape was the preferred oviposition substrate, we detected significant differences among populations. In addition, within population analysis showed that the genotype by resource interaction was significant in all populations. These results indicate that D. melanogaster populations harbour substantial levels of variation and that the genotype by resource interaction may be involved in the maintenance of genetic variation for the trait. Finally, our prediction, based on the conserved pattern of choice among populations, is that larval fitness in grape may be greater than in the alternative substrate.