Researchers from the Faculty of Biology, University of Warsaw, grew tobacco plants in a transparent soil system that mimics natural conditions, allowing for a controlled heterogeneous distribution of nutrients. They discovered that when some parts of the roots had access to Zn while others did not, the Zn‑deficient roots did not show the usual Zn deficiency response. This suggested a previously unknown distribution of Zn within the root system, from “Zn‑sufficient” roots to “Zn‑deficient” ones.
To confirm that Zn was redistributed within the plant body, a collaboration with the POLYX beamline team was established to use micro X‑ray fluorescence (μXRF) imaging at the Polish National Synchrotron Radiation Center SOLARIS. This state of the art technique enabled them to visualize Zn distribution at high resolution directly in plant tissues. The analyses revealed that under uneven Zn conditions, the element accumulated evenly in the root system but, surprisingly, there was a preferential accumulation of Zn in the leaf veins, providing new insight into potential Zn distribution routes. The researchers also linked these physiological changes to the activity of key Zn transports, such as NtZIP4B (a Zn importer), NtHMA4a/b (Zn exporters), and NtNAS (a Zn chelator). Interestingly, the position of Zn in the soil—whether in upper or lower layers—affected how strongly genes coding these transporters were expressed and how much Zn reached the leaves.
Read more on the SOLARIS website
Image: The figure shows series of experiments about plants coping with uneven access to zinc in the soil. Using an innovative “transparent soil” system and micro‑XRF at SOLARIS, scientists from the University of Warsaw observed how roots transport zinc from zones with sufficient supply to zinc‑deficient parts of the root system, ensuring stable plant growth. This discovery opens new perspectives for sustainable fertilization and improving crop quality.





