THE GENETIC ARCHITECTURE OF A COMPLEX ECOLOGICAL TRAIT: HOST PLANT USE IN THE SPECIALIST MOTH, HELIOTHIS SUBFLEXA
Article first published online: 12 JUL 2012
© 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.
Volume 66, Issue 11, pages 3336–3351, November 2012
How to Cite
Oppenheim, S. J., Gould, F. and Hopper, K. R. (2012), THE GENETIC ARCHITECTURE OF A COMPLEX ECOLOGICAL TRAIT: HOST PLANT USE IN THE SPECIALIST MOTH, HELIOTHIS SUBFLEXA. Evolution, 66: 3336–3351. doi: 10.1111/j.1558-5646.2012.01712.x
- Issue published online: 25 OCT 2012
- Article first published online: 12 JUL 2012
- Accepted manuscript online: 11 JUN 2012 01:51PM EST
- Received November 10, 2011 Accepted May 19, 2012 Data Archived: doi:10.5061/dryad.r4c7r
- Complex phenotypes;
- ecological genetics;
- ecologically adaptive traits;
- herbivore host range;
- plant–insect interactions
We used genetic mapping to examine the genetic architecture of differences in host plant use between two species of noctuid moths, Heliothis subflexa, a specialist on Physalis spp., and its close relative, the broad generalist H. virescens. We introgressed H. subflexa chromosomes into the H. virescens background and analyzed 1462 backcross insects. The effects of H. subflexa-origin chromosomes were small when measured as the percent variation explained in backcross populations (0.2–5%), but were larger when considered in relation to the interspecific difference explained (1.5–165%). Most significant chromosomes had effects on more than one trait, and their effects varied between years, sexes, and genetic backgrounds. Different chromosomes could produce similar phenotypes, suggesting that the same trait might be controlled by different chromosomes in different backcross populations. It appears that many loci of small effect contribute to the use of Physalis by H. subflexa. We hypothesize that behavioral changes may have paved the way for physiological adaptation to Physalis by the generalist ancestor of H. subflexa and H. virescens.