Chemoecology (2006) 16, 241-251
N. E. Fatouros, M. Hilker, J. Gross (2006)
Reproductive isolation between populations from Northern and Central Europe of the leaf beetle
Chemoecology 16 (4), 241-251
Abstract: Allopatric populations of the leaf beetle
Chrysomela lapponica are known to feed upon either willow
(Salicaceae) or birch (Betulaceae). This study aimed to elucidate
the differentiation process of these allopatric populations.
We investigated whether these allopatric populations
specialized on different host plants are still able to produce
fertile offspring when interbreeding. Individuals from a
population in Finland (willow specialists) and one in the
Czech Republic (birch specialists) were crossed in laboratory.
Hybrid formation succeeded only between females
from the Czech, birch specialized population and males
from the Finnish, willow specialized population, while no
eggs were produced by females of the willow specialists
having mated males of the birch specialists. Behavioral,
morphological, physiological, and chemical features of the
F1 hybrids were studied. The chemical composition of larval
defensive secretion and feeding preferences of the resulting
F1 hybrids mainly showed similarities with the paternal phenotype,
while the area of black coloring on the offspring’s
elytra was intermediate between those of the parental elytra.
F1 hybrids did not accept the host plant (birch) of their
mothers for feeding and only survived on willow. Thus, since
mothers only lay eggs on birch, we found evidence for a
postzygotic isolation mechanism between the individuals of
the two investigated populations: when having been mated
with willow specialized Finnish males, the birch specialized
Czech mothers place the hybrid eggs on a plant species
(birch), on which the hatching larvae cannot survive.
(The abstract has been supplied by the author or ISPI and is excluded from the Creative Commons licence.)
Database assignments for author(s): Jürgen Gross, Monika Hilker
Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
population dynamics/ epidemiology
Pest and/or beneficial records:
| Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
|---|---|---|---|---|
| Chrysomela lapponica | Willow (Salix) | Finland | ||
| Chrysomela lapponica | Birch (Betula) | Czech Republic |
