Aluminum alert: metal toxicity mechanism curbing plant growth uncovered.

An international team that includes researchers from Elettra Sincrotrone Trieste sheds light on a toxicity mechanism of aluminum in cultivated terrainsand reveals howthis metal restrains plant growth. 

Over the past 40 years one third of cultivable land worldwide has gone wasted because it was found to be no longer productive. One of the major elements to blame for this is aluminum, which represents a particular problem owing to its acid components: approximately 40% of agricultural land worldwide.
In these terrains minerals dissolve and release metal in solution which then checks plant growth. Despite the fact that the effects of aluminum have been known since the early Twentieth century, the reasons behind its toxicity have never been truly explained.
Thanks to a combination of techniques and to the TwinMic microscope, which uses Elettra’s synchrotron light beams, the research team has taken the first “snapshot”of how aluminum accumulates in the roots of soy seeds depending on the duration of exposure.
The research has shown that the toxic impact of aluminum occurs very rapidly and starts five minutes after the beginning of exposure to this metal. It is due to a direct inhibition of the elongation of specific cells at the top of the roots which are directly responsible for their growth.
“By using the TwinMic and the X-ray fluorescence technique–comments Alessandra Gianoncelli, researcher at Elettra –we have succeeded in obtaining a number of chemical maps showing how aluminum concentrates in the cell walls, preventing wall stress relaxation, as well as the necessary elongation. In this manner the roots are unable to grow and the plant is unable to access the water and nutrients required in order complete the reproductive cycle. The effect is clearly visible in just a few minutes, but even after 24 hours the cells in which aluminum has accumulated are still the ones located in the same area as the roots”.
“This research–states Peter Kopittke from Queensland University in Australia and corresponding author for the paper–is crucial for developing strategies capable of hindering the loss of agricultural land. Indeed, a possibile solution for protecting agricultural production requires making crops resistant to aluminum. For this purpose, knowledge on the accumulation and activity mechanisms of this metal, both at the cellular and and the subcellular levels, is essential”.
The research has been published on the journal Plant Physiology and is the result of a collaboration between Queensland University (Australia), University of South Australia, Oxford University and Elettra Sincrotrone Trieste.

Last Updated on Tuesday, 06 November 2018 11:56