We study marine macrophytes from a fundamental as well as an applied perspective. Our long-term research goal is to understand functional-trait variation at the molecular level and rapid mechanisms of adaptation to environmental changes; and to apply this knowledge towards predictive models and monitoring of coastal systems as well as towards sustainable growth of economically important algae, including improvement of kelp stress tolerance to secure growth and production under rapid environmental change.
From Jueterbock et al. (2021) Front. Mar. Sci. Figure by Antoine Minne.
Our current research focus centers on stress-priming. This research carries significant implications for the kelp mariculture industry as it has the potential to transform it by enabling the development of superior kelp strains while preserving genetic diversity. Unlike traditional breeding, which is a time-consuming process that can lead to reduced genetic diversity, our early findings suggest that stress-priming offers a more expedient solution. It not only enhances kelp yield but also fortifies their capacity to withstand environmental stressors. While priming is an established pre-sowing technique in agriculture and horticulture where seeds are partially hydrated and exposed to specific environmental conditions before planting, its transfer and adjustment to the specific life-cycle of kelp is novel.
The urgency of this research is underscored by the imminent threat of rising temperatures associated with climate change, which poses a significant risk to kelp ecosystems. For instance, the kelp species Saccharina latissima almost disappeared from southern Norway due to summer temperatures exceeding 20°C.
This approach could pave the way for the rapid improvement of kelp strains, effectively enhancing their productivity and resistance to environmental stressors. The ultimate goal is to establish stress-priming as a viable bio-engineering technique in kelp cultivation, with a primary focus on commercially valuable kelp species such as Saccharina latissima and Alaria esculenta. If successful, this research has the potential to initiate further studies aimed at mitigating various stressors through engineered epigenetic pathways, and triggering cross-priming effects such as enhanced resistance to bio-fouling and pathogens. This research line is supported by significant grants, notably a 10 million NOK grant from the Norwegian Research Council, and has the potential to lay the foundation for pioneering advancements in kelp biotechnology beyond the funding period, which concludes in 2026.
Figure by Ananya Khatei
Epigenetic factors, such as DNA methylation, miRNAs, and histone modifications regulate gene expression, and play an integral role in development, stress response, and acclimation to environmental challenges. Related to priming, we are interested in the molecular mechanisms that underly the build-up of a memory of environmental conditions that can explain trans-generational inheritance of stress-induced traits.
In collaboration with the Marine Botany Group at Bremen University (Germany), we have shown that rearing temperature determines the level of DNA methylation in sporophytes of the kelp S. latissima, which is a promising first result suggesting the build-up of a molecular stress memory. However, it remains unclear whether and for how long these methylation patterns are memorized and affect phenotypic characteristics via gene expression. However, our early results suggest that brown algae present very low methylation levels and do not encode certain methyltransferases in their genomes and, thus, the functional role of the brown algal methylome in relation to other epigenetic mechanisms is yet unknown.
A milestone for molecular knowledge in macro-algae is set by the Phaeoexplorer project. This project builds genome and transcriptome data for 72 species of brown algae and, thus, allows to understand functional-trait variation at the molecular level. We contribute to exploit this genome resource to identify regulatory regions (e.g. CpG islands), and enzymes (e.g. methyl-transferases) involved in DNA methylation.
Moreover, we use a population-genomics approach to characterize the effect of sugar kelp cultivation on genetic diversity and potential signatures of inadvertent selection induced by cultivation techniques (e.g. repeated clonal propagation).
Top Ten Recommended Species for Inclusion in a Monitoring Program. These selections were made in collaboration with members of the Norwegian Seaweed Association within the sustainability cluster. Notably, as depicted in the image, half of these species are categorised under “Biofouling”. Figure from Johana Jaramillo Guzman.
We are developing a research line that aims to quantify the biotic impact, as well as ecosystem services that a rapid growth of the European macroalgal industry would entail. This allows to identify boundaries of the system’s carrying capacity beyond which production growth would compromise ecological sustainability. Since the first commercial concessions in 2014, annual cultivation of kelp species in Norway has surged to 249 tons in 2021, valued at 6.3 million NOK. The industry could theoretically reach 16,000 tons annually, with a projected value of 4 billion € by 2050. However, challenges surrounding environmental risks, regulation, and sustainability must be addressed. Currently, Norwegian seaweed farmers are not required to report on sustainability, but increasing demand from food producers necessitates the establishment of a monitoring program. In collaboration with the Norwegian Seaweed Association, we are developing a reference database for genetic barcodes and implement environmental DNA (eDNA) techniques for standardized monitoring, contributing to the industry’s pursuit of sustainable practices and certification. The automation of environmental monitoring through eDNA-based characterization of ecological communities and the identification of invasive or threatened species, coupled with AI-assisted analysis of surveillance videos, holds immense promise in preventing ecological harm. It also enables the early detection of warning signals necessitating prompt action.
Most important roadmap steps towards sustainable development of the European seaweed industry
We are currently engaged in mapping out a roadmap that allows for sustainable macroalgae farming in Europe. The global aquaculture industry surpassed 110 million tons in 2019, with seaweeds constituting a significant portion, particularly in Asia. However, the European seaweed farming sector, though growing, faces challenges in terms of scale and sustainability. Our research aims to address critical research gaps and regulatory instruments. This research line emphasizes the need for a balanced approach that considers the environmental, economic, and social sustainability dimensions. We aim to emphasize the industry’s potential to create value beyond economic growth, integrate seamlessly into existing industries, engage local communities as active contributors, and ensure the coexistence of different sustainability dimensions. This relatively new industry has a real chance to move away from equating biomass increase with economic growth and instead make decisions based on the system’s carrying capacity and defined threshold values. The implementation of these roadmap steps will require multidisciplinary collaboration involving academia, governance, and industry partners.