What makes plants tolerant to nutrient fluctuations? An international research team led by the Technical University of Munich (TUM) and involving the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) has investigated this question on the micronutrient boron. The researchers analyzed 185 gene data sets from the model plant Arabidopsis. Their goal is to then be able to transfer the findings to the important crop plant rapeseed.
Andreas Heddergott / TUM Boron is one of the key micronutrients for the growth and fertility of many plants. However, extreme weather events reduce the availability of this nutrient: drought reduces boron uptake, while flooding washes the nutrient out of the soil - less boron reaches the plants. In the context of climate change, this deficiency represents an additional stressor for plants. Their tolerance to these fluctuations is a decisive factor in determining their yields.
Lateral roots extend search radius
Researchers at TUM analyzed 185 subgroups of the species Arabidopsis thaliana from all over the world and searched for boron-efficient plants. Seven of them-especially those from boron-poor soils in Northern Europe-were able to grow well even with little boron. "Each of these plants may have developed different strategies to cope well with boron deficiency," explains Prof. Patrick Bienert , Professor of Crop Physiology at TUM. Some are particularly good at absorbing boron, while others make better use of even these small amounts of boron.
The team's analysis revealed a common adaptation in the root architecture. When boron is scarce, boron-efficient plants go in search of food: they are able to grow long, lateral roots, thus increasing their radius for nutrient uptake.
Genes for boron efficiency identified
The genetic mechanisms that control boron efficiency in plants are still poorly understood. In their work, the researchers identified gene regions responsible for boron utilization and uptake in roots and shoots. These findings could help breed nutrient-resilient plants.
Transfer to crop plants
Building on these results, the researchers are now investigating the crop plant rapeseed. Since rapeseed, like Arabidopsis, is a cruciferous plant, the researchers are optimistic that they will be able to transfer the findings and soon obtain promising results.
"Crop plants are usually more sensitive to abiotic stressors, such as fluctuating micronutrient supply," explains Patrick Bienert. "We want to find particularly efficient individuals, identify their strategies, and then breed these traits into lines that deliver high yields. This could result in plants that are both high-yielding and more climate-resilient."
Alcock TD, Bienert MD, Junker A et al. Arabidopsis thaliana exhibits wide within-species variation in tolerance to boron limitation and root and shoot trait resilience associate with a pleiotropic locus. New Phytologist. 2025. https://doi.org/10.1111/nph.70570
