Silene nutans (Caryophyllaceae) is a gynodioecious species, i.e. hermaphrodite and male-sterile plants can be found in populations due to cytonuclear interactions. We have shown by analysing genetic diversity at both cytoplasmic and nuclear levels on a large geographic survey, that S. nutans is composed of distinct genetic lineages (western and eastern) which are most likely the result of past glaciation events (Martin et al 2016). Hybrids between western an eastern lineages are chlorotic and exhibit a high rate of juvenile mortality. Interestingly, the intensity of this reproductive isolation depends on the nature of the cytoplasm and therefore suggests the involvement of cytoplasmic genetic incompatibilities. Their emergence could have been facilitated thanks to the peculiar evolutionary dynamics of gynodioecy in the species (Martin et al 2017).
We will discuss the strategies we are conducting to understand this fast phenomenon of speciation in Silene nutans.
MartinH, TouzetP, Van RossumF, Delalande D, ArnaudJ-F (2016) Phylogeographic pattern of range expansion provides evidence for cryptic species lineages in Silene nutans in Western Europe. Heredity 116, 286-294
Martin H, Touzet P, Dufay M, Godé C, Schmitt E, Lahiani E, Delph LF, Van Rossum F (2017) Lineages of Silene nutans developed rapid, strong, asymmetric post-zygotic reproductive isolation in allopatry. Evolution 71, 1519- 153