Why Plants Follow the Sun

While the observation that plants follow the sun has been recorded since the 15^th Century, how this was scientifically achieved and why this occurred remained a mystery for years. But a team of European scientists may have solved the mystery and they say that the answer lies in a class of plant hormone called auxin. Scientists from the Vrije Universiteit Brussel (VIB) and University of Ghent in Belgium have identified that auxin is stored at specific sites in the plant.

The scientists led by Elke Barbez, with supervision from Jürgen Kleine from VIB and Jirí Friml, also from VIB and the University of Ghent, found out that auxin transport within the plant plays a vital and complex role. Auxin is produced in the growing sections of the plant before it is sent to other parts where it is needed, including the stem. For the plant to best absorb sunlight, the stem needs to straighten out as soon as possible. More auxin is then delivered to the underside of the stem than to the topside, resulting with the underside growing faster and the stem straightening out. If auxin transport is regulated, plants are able to take full advantage of local and changing conditions.

The researchers said that their findings will benefit agricultural scientists and farmers. They added that increasing auxin levels at the right moment in the right place would result in better growth and increased yields.

Read more about this research at http://phys.org/news/2012-05-sun_1.html. The Nature article is available at http://www.nature.com/nature/journal/v485/n7396/full/nature11001.html.