New research by a team of German and French scientists has shown that plants release chemical poisons to destroy neighbouring plants in their bid for more space and sunlight. The poisons released are deadly and that poison change the very genetic structure of the victim plant preventing its growth and ultimately leading to its death.
The existence of this chemical warfare, called to as 'allelopathy'. Allelopathy is widespread among many plant species, and has been known for a long time to scientists and agriculturists. But what had remained a mystery was how this strategy works. This appears to have been solved by the scientists.
Work by Sascha Venturelli of the University of Tubingen, Germany and colleagues now sheds light on the inner workings of this plant chemical warfare. The scientists found plants release chemical compounds from their roots into the soil and where the substances decay or are modified by microbes. Some of these substances are toxic when the roots of neighboring plants take them up.
Claude Becker, of the Max Planck Institute for Developmental Biology, Tubingen and one of the leaders of the study, explains the importance of the findings: "The phenomenon has been known for years, and many classes of allelochemicals have been identified over the last decades, but for first time we now understand the molecular mechanism of such a 'territorial behaviour' of plants".
The scientists discovered the role a chemicals known as DIBOA and DIMBOA. These are released by several grass species, and their degradation products are well known for their toxicity. They alter the chemical structure of DNA leading to changed gene expression.
The scientists in the model plant Arabidopsis thaliana, found that inhibition of histone deacetylases by the plant toxins lead to more histone acetylation and an increase in gene expression, ultimately causing plant growth to slow down.
Allelochemicals are important regulators in natural and agricultural plant communities, and have repeatedly been associated with the success of invasive species in their new habitats. But there is more: there could be a link to fighting cancer too.
Venturelli Says "Herbal natural products in general hold great potential for the therapy of human diseases, We have found that these particular compounds efficiently inhibit the growth of human cancer cells, too."