Heterozygosity maintains developmental stability of sternopleural bristles in Drosophila subobscura interpopulation hybrids

Zorana Kurbalija Novicic1a*, Marina Stamenkovic-Radak1,2, Cino Pertoldi3,4, Mihailo Jelic2, Marija Savic Veselinovic2, Marko Andjelkovic1,2

1Institute of Biological Research, University of Belgrade, Despot Stefan Blvd. 142, 11000 Belgrade, Serbia
2Faculty of Biology, University of Belgrade, Studentski trg 3, 11000 Belgrade, Serbia
3Department of Ecology and Genetics, Institute of Biological Science, University of Aarhus, Ny Munkegade, Building 540, DK8000 Aarhus C, Denmark
4Mammal Research Institute, Polish Academy of Sciences, 17-230 Białowieża, Poland

Abstract

Interpopulation hybridization can lead to outbreeding depression within affected populations due to breakdown of coadapted gene complexes or heterosis in hybrid populations. One of the principal methods commonly used to estimate the level of developmental instability (DI) is fluctuating asymmetry (FA). We used three genetically differentiated Drosophila subobscura populations according to inversion polymorphism analysis and measured the variability of sternopleural bristle number and change in FA across generations P, F1, and F2 between intraand interpopulation hybrids of D. subobscura. The mean variability of sternopleural bristle number in intra- and interpopulation hybrids of D. subobscura across generations cannot determine whether the changes at the level of developmental homeostasis are due exclusively to genomic coadaptation or to heterozygosity. Phenotypic variance (Vp) and FA of sternopleural bristle number was higher in interpopulation than in intrapopulation hybrids across generations. F1 hybrids were more developmentally stable compared to each parental population in both intraand interpopulation hybrids. The most probable mechanism providing developmental homeostasis is heterozygote or hybrid superiority, also called overdominace. However, Vp was higher and FA lower in the F2 generation when compared to F1, due mainly to crossing-over in the formation of F2.

Keywords: developmental homeostasis, fluctuating asymmetry, genome coadaptation, hybridization, phenotypic variance

Abbreviations: DI, developmental instability; FA, fluctuating asymmetry; Vp, phenotypic variance

Correspondence: a kurbalija@ibiss.bg.ac.rs

Editor: Mariana Wolfner was Editor of this paper.

Received: 30 August 2010 | Accepted: 17 Feburary 2011 | Published: 31 August 2011

ISSN: 1536-2442 | Volume 11, Number 113

Novicic ZK, Stamenkovic-Radak M, Pertoldi C, Jelic M, Veselinovic MS, Andjelkovic M. 2011. Heterozygosity maintains developmental stability of sternopleural bristles in Drosophila subobscura interpopulation hybrids. Journal of Insect Science 11:113 available online: insectscience.org/11.113