Plant galaxy

Although this burst of colour is reminiscent of the formation of a planetary nebula, the distances here are measured not in light years but in micrometres. This is in fact a cross-section of a root of "Arabidopsis thaliana", an iconic plant model for biologists. With the help of molecular marking techniques derived from bioorthogonal chemistry, scientists were able to use red, green and yellow fluorescence to distinguish the three components of lignin, a substance that gives plants their rigidity. This innovative marking process makes it possible to observe structural changes in plant walls in response to climatic stress or pathogen attack.