Abstract

Development of multiple embryos from a single zygote, the phenomenon called monozygotic polyembryony, is a widespread reproductive strategy found in higher plants and especially in gymnosperms. The enigma of plant monozygotic polyembryony is that only one embryo in a polyembryonic seed usually survives while the others are eliminated at an early stage. Here we report that programmed cell death (PCD) is the major mechanism responsible for elimination of subordinate embryos in a polyembryonic seed. Using post-fertilized pine (Pinus sylvestris) ovules, we show that once the dominant embryo is selected and, subsequently, the entire female gametophyte is affected by PCD, the cells of subordinate embryos initiate an autolytic self-destruction program. The progression of embryonic PCD follows a rigid basal-apical pattern, first killing the most basally situated cells, adjacent to the suspensor, and then proceeding towards the apical region until all cells in the embryonal mass are doomed. Our data demonstrate that during polyembryony, PCD serves to halt competition among monozygotic embryos in order to ensure survival of one embryo.

Keywords

programmed cell death; polyembryony; plant seed; embryo competition; female gametophyte; embryo elimination

Published in

Cell Death and Differentiation
2002, Volume: 9, number: 10, pages: 1057-1062

SLU Authors

• Stålhandske, Lada

  • Department of Forest Genetics, Swedish University of Agricultural Sciences
    

• Von Arnold, Sara

  • Department of Forest Genetics, Swedish University of Agricultural Sciences
    

• Daniel, Geoffrey

  • Department of Wood Science, Swedish University of Agricultural Sciences
    

• Bozhkov, Peter

  • Department of Forest Genetics, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Forest Science
Developmental Biology


Publication identifier

DOI: https://doi.org/10.1038/sj.cdd.4401068

Permanent link to this page (URI)

https://res.slu.se/id/publ/109905