Completely lost in teaching until early december (that is, soon). To the exception of the coming edition of Berry Go Round due in a few days. So I let you with another abstract (from American Journal of Botany) to consider (woot woot! :)
I like this paper, because the very first version was submitted as we were (well, not all of us) late grad students. Got rejected, but there was some reason. Than it slept deep in a drawer because so many more projects were leading us somewhere else. But then, we were on our way to being sort of scooped… In a hurry, we decided to not let it go that way, and eventually ended up with something somewhat more pleasing (+ it was the opportunity to reemphasize unexpected and -yes I tell you so– interesting results). In short, I enjoyed the maturation process much, and I’m quite happy with not being too late to publish “old” data and not being scooped at the end… The paper version will appear in December.
Early inbreeding depression in the sexually polymorphic plant Dianthus sylvestris (Caryophyllaceae): Effects of selfing and biparental inbreeding among sex morphs
Carine L. Collin, Laurent Penet and Jacqui A. Shykoff
Predominantly outcrossing plant species are expected to accumulate recessive deleterious mutations, which can be purged when in a homozygous state following selfing. Individuals may vary in their genetic load because of different selfing histories, which could lead to differences in inbreeding depression among families. Lineage-dependent inbreeding depression can appear in gynodioecious species if obligatory outcrossed females are more likely to produce female offspring and if partially selfing hermaphrodites are more likely to produce hermaphrodites. We investigated inbreeding depression at the zygote, seed, and germination stages in the gynomonoecious-gynodioecious Dianthus sylvestris, including pure-sexed plants and a mixed morph. We performed hand-pollinations on 56 plants, belonging to the three morphs, each receiving 2–3 cross treatments (out-, sib- and self-pollination) on multiple flowers. Effects of cross treatments varied among stages and influenced seed provisioning, with sibling competition mainly occurring within outcrossed fruits. We found significant inbreeding depression for seed mass and germination and cumulative early inbreeding depression varied greatly among families. Among sex morphs, we found that females and hermaphrodites differed in biparental inbreeding depression, whereas uniparental was similar for all. Significant inbreeding depression levels may play a role in female maintenance in this species, and individual variation in association with sex-lineages proclivity is discussed.
Key Words: biparental inbreeding • Caryophyllaceae • Dianthus sylvestris • female advantage • gynomonoecy-gynodioecy • germination rates • inbreeding depression • maternal investment • seed mass • seed number • sibling competition • uniparental inbreeding