University of Warwick scientists reported in the journal Science the first
evidence that plants have evolved ways to control embryo growth and
development by emitting information from surrounding cells. Dr. Jose
Gutierrez-Marcos from Warwick's School of Life Sciences discovered that
female sex cells and the placenta-like endosperm in plant seeds transmit
specific signals to developing embryos to help direct their growth

Plant embryos are located in seeds and when these germinate, they give rise
to the adult plant. It was previously believed that embryo development was
determined by the genetic content of the embryo alone. However, the new
study showed that specific cell-types present in the embryo environment can
send out protein signals to also influence this process. This is similar
with the scenario occurring in mammals whereby embryo development is
controlled by signals sent out by neighbouring placental cells.

Understanding how these cells of non-embryonic origin can influence
developing plant embryos, the researchers argue, is key to creating new,
improved plant species including advantageous hybrid crops, where at present
embryos often fail to develop properly when distantly-related parents are
used.

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