‘Pale’ barley: a promising avenue for more resilient agriculture

Contrary to popular belief, a less green plant is not necessarily less productive. Researchers believe that a slight reduction in chlorophyll could allow for a better distribution of light within the plant canopy. As the upper leaves absorb less light, more light would be available to the lower leaves, thereby optimising photosynthesis across the entire crop.

The GREENSCALE project, coordinated in France by Fabien Chardon (Institut Jean-Pierre Bourgin – Plant Sciences) and Jean Alric (CEA CADARACHE), aims to assess the potential of these low-chlorophyll barley lines. Although long overlooked in variety selection due to their lighter colour, these plants could nevertheless maintain, or even improve, their agronomic performance.

The trials, conducted in partnership with Arvalis, aim to measure their behaviour under different climatic and water conditions. The data collected will also be used to feed into models designed to assess their impact on the functioning of crops and ecosystems.

One of the main challenges concerns reducing nitrogen requirements. As chlorophyll is rich in nitrogen-containing proteins, a plant with lower chlorophyll content might require less fertiliser without compromising yield. Researchers therefore hope to reduce the carbon footprint of agricultural production, whilst also cutting fertiliser costs. Initial research suggests a potential saving of 5 to 10 per cent in nitrogen use for cereals.

At the same time, a slight reduction in pigmentation could also help to limit the temperature of the plant canopy and reduce evapotranspiration, thereby improving crops’ tolerance to periods of drought and extreme heat.

This research illustrates a new approach to plant breeding: rather than systematically increasing performance, it seeks to optimise plant function in order to balance productivity, reduced input requirements and adaptation to climate change.

To study these mechanisms, Fabien Chardon combines physiological, genetic and molecular analytical approaches. He is also interested in the natural diversity of plants, which is a valuable source for identifying favourable traits. His research is conducted at various scales, from the cell to the whole plant, right through to field growing conditions, with the aim of contributing to the development of more resource-efficient agricultural systems.

Voir aussi 

[GREENSCALE FOCUS] – Photosynthesis trials at the Villiers-le-Bâcle site.

The GREENSCALE project 
 

 

Fabien Chardon 

Fabien Chardon is a research director at INRAE, co-leader of the SATURNE team and scientific lead for the OV-Culture Plantes platform at the Jean-Pierre Bourgin Institute in Versailles. He is also co-coordinator of the GREENSCALE project within the PEPR FairCarboN programme, which aims to gain a better understanding of carbon assimilation efficiency in barley genotypes with low chlorophyll content.

His research focuses on how plants acquire, store and recycle their resources – particularly nitrogen and carbon – to support their growth throughout their life cycle, including when faced with adverse conditions. In particular, this work seeks to understand how plants can produce more with fewer inputs, whilst maintaining their growth and crop quality.