The bonsai effect: Wounded plants make jasmonates, inhibiting cell division, stunting growth

November 11, 2008

It is well known that plants growing under unfavourable conditions are generally smaller than those growing in stress-free conditions: indeed it is estimated that in the US, abiotic stress reduces the yield of agricultural crops by an average of 22%. A spectacular example of the effect of stress – in this case, repeated wounding – on plant growth is given by bonsai trees, in which every aspect of their stature, including height, girth, and size of leaves, is uniformly reduced to as little as 5% of that of their untreated sister trees. However, the mechanism of wound-induced stunting remains obscure.

Plant growth results from divisions of "stem cells" in apical meristems that are located in the very tips of green shoots and roots. The shoot apical meristems are not only tiny, (0.1 to 0.3 mm diameter), but are normally hidden from view by the very young leaves emerging from the base of the meristem. Thus, the initial growth and shape of leaves is by cell division, and more than 90% of leaf growth is by subsequent cell expansion.

Reporting in the online, open-access journal PLoS ONE on November 11, Yi Zhang and John Turner at the University of East Anglia found that when leaves of the model plant Arabidopsis are wounded, cell division in the apical meristem is reduced, growth of the plant is arrested within days, and the new leaves grow to only one-half of their normal size although the size of leaf cells is unaffected.

Unexpectedly, the suppression of cell division in the apical meristem occurs through a signal pathway initiated by the wound hormone, jasmonate, which is synthesised in the damaged mature leaves. Mutant Arabidopsis lines unable to synthesise or to respond to jasmonate are not only larger than normal plants, but their growth is not reduced by the wound stress.

The researchers note that this finding opens the possibility of improving crop growth through the manipulation of the jasmonate signal pathway.

Citation: Zhang Y, Turner JG (2008) Wound-Induced Endogenous Jasmonates Stunt Plant Growth by Inhibiting Mitosis. PLoS ONE 3(11): e3699. doi:10.1371/journal.pone.0003699 dx.plos.org/10.1371/journal.pone.0003699

Source: Public Library of Science

Explore further: Researchers demonstrate how gram-negative bacteria deliver toxins to kill neighboring bacteria

Related Stories

Shedding light on millipede evolution

August 2, 2015

As an National Science Foundation (NSF)-funded entomologist, Virginia Tech's Paul Marek has to spend much of his time in the field, hunting for rare and scientifically significant species. He's provided NSF with an inside ...

Recommended for you

Just how good (or bad) is the fossil record of dinosaurs?

August 28, 2015

Everyone is excited by discoveries of new dinosaurs – or indeed any new fossil species. But a key question for palaeontologists is 'just how good is the fossil record?' Do we know fifty per cent of the species of dinosaurs ...

Fractals patterns in a drummer's music

August 28, 2015

Fractal patterns are profoundly human – at least in music. This is one of the findings of a team headed by researchers from the Max Planck Institute for Dynamics and Self-Organization in Göttingen and Harvard University ...

Smart home heating and cooling

August 28, 2015

Smart temperature-control devices—such as thermostats that learn and adjust to pre-programmed temperatures—are poised to increase comfort and save energy in homes.

Smallest 3-D camera offers brain surgery innovation

August 28, 2015

To operate on the brain, doctors need to see fine details on a small scale. A tiny camera that could produce 3-D images from inside the brain would help surgeons see more intricacies of the tissue they are handling and lead ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.