Microbiota-driven genetic switch could promote plant leaf growth

The study developed during the PhD of Valéria Custódio, in collaboration with the University of Nottingham, identifies a microbiota-driven mechanism in plants that promotes leaf growth and allows plants to adapt to a nutrient deficient environment.

In nature, plant leaves are colonized by microbes that are essential for their survival and health. However, the extent to which microbial communities shape leaf growth remains poorly understood. In this new study published in Cell Host & Microbe, the team found that microbes colonizing plant leaves influence leaf growth, independently of nutrient concentration and soil properties.

The research carried out by Green-it member and ITQB NOVA alumni Valéria Custódio during her PhD, investigated leaf growth in three soils with different amounts of nutrients and identified leaf growth promotion driven by microbiota. The team designed a bacterial community and recolonized the maize plants so they could study the microbiota-mediated mechanisms involved in leaf growth.

Through transcriptomic analysis, the researchers found that the beneficial effect of microbiota in leaf growth was mainly due to the repression of genes involved in plant defense. This mechanism is responsible for balancing leaf growth through the growth-defense trade-off. Additionally, this mechanism could intersect with other branches of the leaf growth regulatory circuit to establish a hierarchy of biotic or abiotic stress responses to ensure plant survival in nature, where multiple stresses are present. These findings could help engineer leaf microbiota in order to increase plant growth in nutrient deficient soils.

Valéria Custódio developed her PhD at ITQB NOVA between 2016 – 2023, supervised by Professor Margarida Oliveira, Dr. Martin R. Broadley and Dr. Gabriel Castrillo, focusing on the role of soil microbiota and environmental cues on the regulation of maize development.

Read the full paper:

Custódio V, Salas-González I, Gopaulchan D, Flis P, Amorós-Hernández R, Gao YQ, Jia X, Moreno Â, Carrera E, Marcon C, Hochholdinger F, Oliveira M, Salt D, Castrillo G, 2025. Individual leaf microbiota tunes a genetic regulatory network to promote leaf growth. Cell Host & Microbe. DOI: 10.1016/j.chom.2025.02.002