Selfed embryo death in Pinus taeda: a phenotypic profile
Article first published online: 17 JAN 2008
© The Author (2008)
Volume 178, Issue 1, pages 210–222, April 2008
How to Cite
Williams, C. G. (2008), Selfed embryo death in Pinus taeda: a phenotypic profile. New Phytologist, 178: 210–222. doi: 10.1111/j.1469-8137.2007.02359.x
- Issue published online: 17 JAN 2008
- Article first published online: 17 JAN 2008
- Received: 15 September 2007Accepted: 26 November 2007
- diplohaplontic life cycle;
- embryo lethal system;
- inbreeding depression;
- programmed cell death;
- • Selective elimination of selfed embryos, or inbreeding depression, is shared among many members of the Pinaceae but it has not been fully characterized at the phenotypic level.
- • Here, two death pattern model hypotheses are tested using 10 621 Pinus taeda embryos sampled in two cohorts. Cones from a single pedigree based on selfed, outbred, parent–offspring and offspring–parent matings were destructively sampled weekly before, during and after fertilization.
- • Selfed embryo deaths adhered to two patterns over the course of development: death was linear with respect to days from fertilization; and a stage-specific death peak occurred during the early embryogeny stage. This death peak occurred from 23 to 36 d after fertilization in the 2004 cohort and from 27 to 34 d after fertilization in the 2006 cohort. Of those selfed embryos that died, 64–83% died at stages where a single dominant embryo was elongating inside the female gametophyte.
- • Additional genetic models are needed to account for the stage-specific death component of selfed P. taeda embryos.