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

Nov 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: Compact wool measurement tool may find home on the range

add to favorites email to friend print save as pdf

Related Stories

The year ahead in science

Jan 05, 2015

Some serious groundwork has been laid. Some amazing instruments are turning on. Some incredible destinations are in sight. If you ask us, 2015 is going to be an awesome year in science.

How vitamin C helps plants beat the sun

Jan 05, 2015

While vitamin C in plant chloroplasts is known to help prevent a reduction in growth that plants experience when exposed to excessive light—phenomenon called photo inhibition—how it gets into chloroplasts ...

Stem cells born out of indecision

Dec 18, 2014

Scientists at the University of Copenhagen have gained new insight into embryonic stem cells and how blocking their ability to make choices explains why they stay as stem cells in culture. The results have just been published ...

Recommended for you

GMO mosquito plan sparks outcry in Florida

1 hour ago

A British company's plan to unleash hordes of genetically modified mosquitoes in Florida to reduce the threat of dengue fever and other diseases has sparked an outcry from fearful residents.

Population genomics unveil seahorse domain

20 hours ago

In a finding vital to effective species management, a team including City College of New York biologists has determined that the lined seahorse (Hippocampus erectus) is more a permanent resident of the we ...

User comments : 0

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.