A research team from the Instituto de Biología Molecular y Celular de Plantas (IBMCP), a joint center of the Consejo Superior de Investigaciones Científicas (CSIC) and the Universitat Politècnica de València (UPV), has identified key cellular, genetic, and molecular mechanisms that coordinate two concurrent growth programs in plant stems: longitudinal (height) and radial (thickness). The findings were published in the journal Current Biology.
Javier Agustí, a researcher at IBMCP and coordinator of the study, stated, "This coordination is crucial for plant stems to develop in appropriate proportions to ensure sufficient stability through radial growth, which facilitates longitudinal expansion. Our results suggest that the mechanism we identified likely occurs in the vast majority of plant species."
The study also involved experts from the Plant Science Center (UPSC) at Umeå University in Sweden, who worked with two distinct species: the model plant Arabidopsis thaliana, a herbaceous species, and the poplar tree.
This research serves as a model for understanding how various growth programs coordinate during the development of organs in multicellular organisms. Agustí explained that an analogy in humans could be drawn from the development of a limb, where the growth of bones, tendons, muscles, and skin must be coordinated to avoid aberrant forms.
Studying these mechanisms in plant stems is advantageous because only two growth programs coexist: longitudinal and radial, facilitating the identification of basic coordination principles that could be common to other biological systems.
The plant stem, particularly in trees, is composed of tissues that accumulate the most biomass in the ground, forming wood. Understanding the coordination of growth programs during stem development could help maximize biomass production. Agustí pointed out, "Plant biomass consists of carbon polymers, and the source of that carbon is atmospheric CO2. Moreover, wood is a renewable material that supports ecological production in certain industries, such as construction. By maximizing wood production per tree—such as intervening in the coordination of growth programs during development—we would not only enhance our options for more ecological production but also contribute to reducing atmospheric CO2 levels."